Commit Graph

121 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
2414f45b93 Merge 4.14.271 into android-4.14-stable
Changes in 4.14.271
	x86/speculation: Merge one test in spectre_v2_user_select_mitigation()
	x86,bugs: Unconditionally allow spectre_v2=retpoline,amd
	x86/speculation: Rename RETPOLINE_AMD to RETPOLINE_LFENCE
	x86/speculation: Add eIBRS + Retpoline options
	Documentation/hw-vuln: Update spectre doc
	x86/speculation: Include unprivileged eBPF status in Spectre v2 mitigation reporting
	x86/speculation: Use generic retpoline by default on AMD
	x86/speculation: Update link to AMD speculation whitepaper
	x86/speculation: Warn about Spectre v2 LFENCE mitigation
	x86/speculation: Warn about eIBRS + LFENCE + Unprivileged eBPF + SMT
	arm/arm64: Provide a wrapper for SMCCC 1.1 calls
	arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit()
	ARM: report Spectre v2 status through sysfs
	ARM: early traps initialisation
	ARM: use LOADADDR() to get load address of sections
	ARM: Spectre-BHB workaround
	ARM: include unprivileged BPF status in Spectre V2 reporting
	ARM: fix build error when BPF_SYSCALL is disabled
	ARM: fix co-processor register typo
	ARM: Do not use NOCROSSREFS directive with ld.lld
	ARM: fix build warning in proc-v7-bugs.c
	xen/xenbus: don't let xenbus_grant_ring() remove grants in error case
	xen/grant-table: add gnttab_try_end_foreign_access()
	xen/blkfront: don't use gnttab_query_foreign_access() for mapped status
	xen/netfront: don't use gnttab_query_foreign_access() for mapped status
	xen/scsifront: don't use gnttab_query_foreign_access() for mapped status
	xen/gntalloc: don't use gnttab_query_foreign_access()
	xen: remove gnttab_query_foreign_access()
	xen/9p: use alloc/free_pages_exact()
	xen/gnttab: fix gnttab_end_foreign_access() without page specified
	xen/netfront: react properly to failing gnttab_end_foreign_access_ref()
	Linux 4.14.271

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I9f41bca7a4638913cfd2b97006d19185dd9bf584
2022-03-11 11:13:06 +01:00
Josh Poimboeuf
383973dc1a x86/speculation: Include unprivileged eBPF status in Spectre v2 mitigation reporting
commit 44a3918c8245ab10c6c9719dd12e7a8d291980d8 upstream.

With unprivileged eBPF enabled, eIBRS (without retpoline) is vulnerable
to Spectre v2 BHB-based attacks.

When both are enabled, print a warning message and report it in the
'spectre_v2' sysfs vulnerabilities file.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
[fllinden@amazon.com: backported to 4.14]
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-11 10:13:28 +01:00
Maciej Żenczykowski
34073d7a8e BACKPORT: bpf: add bpf_ktime_get_boot_ns()
On a device like a cellphone which is constantly suspending
and resuming CLOCK_MONOTONIC is not particularly useful for
keeping track of or reacting to external network events.
Instead you want to use CLOCK_BOOTTIME.

Hence add bpf_ktime_get_boot_ns() as a mirror of bpf_ktime_get_ns()
based around CLOCK_BOOTTIME instead of CLOCK_MONOTONIC.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
(cherry picked from commit 71d19214776e61b33da48f7c1b46e522c7f78221)
Change-Id: Ifd62c410dcc5112fd1a473a7e1f70231ca514bc0
2021-02-11 19:46:44 -08:00
Yonghong Song
5179a6a673 UPSTREAM: bpf: permit multiple bpf attachments for a single perf event
This patch enables multiple bpf attachments for a
kprobe/uprobe/tracepoint single trace event.
Each trace_event keeps a list of attached perf events.
When an event happens, all attached bpf programs will
be executed based on the order of attachment.

A global bpf_event_mutex lock is introduced to protect
prog_array attaching and detaching. An alternative will
be introduce a mutex lock in every trace_event_call
structure, but it takes a lot of extra memory.
So a global bpf_event_mutex lock is a good compromise.

The bpf prog detachment involves allocation of memory.
If the allocation fails, a dummy do-nothing program
will replace to-be-detached program in-place.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit e87c6bc3852b981e71c757be20771546ce9f76f3)
Signed-off-by: Connor O'Brien <connoro@google.com>
Bug: 121213201
Bug: 138317270
Test: build & boot cuttlefish; attach 2 progs to 1 tracepoint
Change-Id: I25ce1ed6c9512d0a6f2db7547e109958fe1619b6
2019-12-11 20:04:37 -08:00
Alexei Starovoitov
9e61c87b1f UPSTREAM: bpf: multi program support for cgroup+bpf
introduce BPF_F_ALLOW_MULTI flag that can be used to attach multiple
bpf programs to a cgroup.

The difference between three possible flags for BPF_PROG_ATTACH command:
- NONE(default): No further bpf programs allowed in the subtree.
- BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program,
  the program in this cgroup yields to sub-cgroup program.
- BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program,
  that cgroup program gets run in addition to the program in this cgroup.

NONE and BPF_F_ALLOW_OVERRIDE existed before. This patch doesn't
change their behavior. It only clarifies the semantics in relation
to new flag.

Only one program is allowed to be attached to a cgroup with
NONE or BPF_F_ALLOW_OVERRIDE flag.
Multiple programs are allowed to be attached to a cgroup with
BPF_F_ALLOW_MULTI flag. They are executed in FIFO order
(those that were attached first, run first)
The programs of sub-cgroup are executed first, then programs of
this cgroup and then programs of parent cgroup.
All eligible programs are executed regardless of return code from
earlier programs.

To allow efficient execution of multiple programs attached to a cgroup
and to avoid penalizing cgroups without any programs attached
introduce 'struct bpf_prog_array' which is RCU protected array
of pointers to bpf programs.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
for cgroup bits
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 324bda9e6c5add86ba2e1066476481c48132aca0)
Signed-off-by: Connor O'Brien <connoro@google.com>
Bug: 121213201
Bug: 138317270
Test: build & boot cuttlefish
Change-Id: If17b11a773f73d45ea565a947fc1bf7e158db98d
2019-12-11 20:04:15 -08:00
Greg Kroah-Hartman
fd9e32a025 Merge 4.14.122 into android-4.14
Changes in 4.14.122
	net: avoid weird emergency message
	net/mlx4_core: Change the error print to info print
	net: test nouarg before dereferencing zerocopy pointers
	net: usb: qmi_wwan: add Telit 0x1260 and 0x1261 compositions
	ppp: deflate: Fix possible crash in deflate_init
	tipc: switch order of device registration to fix a crash
	vsock/virtio: free packets during the socket release
	tipc: fix modprobe tipc failed after switch order of device registration
	vsock/virtio: Initialize core virtio vsock before registering the driver
	net: Always descend into dsa/
	parisc: Export running_on_qemu symbol for modules
	parisc: Skip registering LED when running in QEMU
	parisc: Use PA_ASM_LEVEL in boot code
	parisc: Rename LEVEL to PA_ASM_LEVEL to avoid name clash with DRBD code
	stm class: Fix channel free in stm output free path
	md: add mddev->pers to avoid potential NULL pointer dereference
	intel_th: msu: Fix single mode with IOMMU
	p54: drop device reference count if fails to enable device
	of: fix clang -Wunsequenced for be32_to_cpu()
	cifs: fix strcat buffer overflow and reduce raciness in smb21_set_oplock_level()
	media: ov6650: Fix sensor possibly not detected on probe
	Revert "cifs: fix memory leak in SMB2_read"
	NFS4: Fix v4.0 client state corruption when mount
	PNFS fallback to MDS if no deviceid found
	clk: hi3660: Mark clk_gate_ufs_subsys as critical
	clk: tegra: Fix PLLM programming on Tegra124+ when PMC overrides divider
	clk: rockchip: fix wrong clock definitions for rk3328
	fuse: fix writepages on 32bit
	fuse: honor RLIMIT_FSIZE in fuse_file_fallocate
	iommu/tegra-smmu: Fix invalid ASID bits on Tegra30/114
	ceph: flush dirty inodes before proceeding with remount
	x86_64: Add gap to int3 to allow for call emulation
	x86_64: Allow breakpoints to emulate call instructions
	ftrace/x86_64: Emulate call function while updating in breakpoint handler
	tracing: Fix partial reading of trace event's id file
	memory: tegra: Fix integer overflow on tick value calculation
	perf intel-pt: Fix instructions sampling rate
	perf intel-pt: Fix improved sample timestamp
	perf intel-pt: Fix sample timestamp wrt non-taken branches
	objtool: Allow AR to be overridden with HOSTAR
	fbdev: sm712fb: fix brightness control on reboot, don't set SR30
	fbdev: sm712fb: fix VRAM detection, don't set SR70/71/74/75
	fbdev: sm712fb: fix white screen of death on reboot, don't set CR3B-CR3F
	fbdev: sm712fb: fix boot screen glitch when sm712fb replaces VGA
	fbdev: sm712fb: fix crashes during framebuffer writes by correctly mapping VRAM
	fbdev: sm712fb: fix support for 1024x768-16 mode
	fbdev: sm712fb: use 1024x768 by default on non-MIPS, fix garbled display
	fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting
	PCI: Mark AMD Stoney Radeon R7 GPU ATS as broken
	PCI: Mark Atheros AR9462 to avoid bus reset
	PCI: Factor out pcie_retrain_link() function
	PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum
	dm cache metadata: Fix loading discard bitset
	dm zoned: Fix zone report handling
	dm delay: fix a crash when invalid device is specified
	xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink
	xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel module
	vti4: ipip tunnel deregistration fixes.
	esp4: add length check for UDP encapsulation
	xfrm4: Fix uninitialized memory read in _decode_session4
	power: supply: cpcap-battery: Fix division by zero
	securityfs: fix use-after-free on symlink traversal
	apparmorfs: fix use-after-free on symlink traversal
	mac80211: Fix kernel panic due to use of txq after free
	KVM: arm/arm64: Ensure vcpu target is unset on reset failure
	power: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG
	iwlwifi: mvm: check for length correctness in iwl_mvm_create_skb()
	sched/cpufreq: Fix kobject memleak
	x86/mm/mem_encrypt: Disable all instrumentation for early SME setup
	ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour
	perf bench numa: Add define for RUSAGE_THREAD if not present
	Revert "Don't jump to compute_result state from check_result state"
	md/raid: raid5 preserve the writeback action after the parity check
	driver core: Postpone DMA tear-down until after devres release for probe failure
	bpf: add map_lookup_elem_sys_only for lookups from syscall side
	bpf, lru: avoid messing with eviction heuristics upon syscall lookup
	btrfs: Honour FITRIM range constraints during free space trim
	fbdev: sm712fb: fix memory frequency by avoiding a switch/case fallthrough
	Linux 4.14.122

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2019-05-27 09:36:03 +02:00
Daniel Borkmann
9f2292309d bpf: add map_lookup_elem_sys_only for lookups from syscall side
commit c6110222c6f49ea68169f353565eb865488a8619 upstream.

Add a callback map_lookup_elem_sys_only() that map implementations
could use over map_lookup_elem() from system call side in case the
map implementation needs to handle the latter differently than from
the BPF data path. If map_lookup_elem_sys_only() is set, this will
be preferred pick for map lookups out of user space. This hook is
used in a follow-up fix for LRU map, but once development window
opens, we can convert other map types from map_lookup_elem() (here,
the one called upon BPF_MAP_LOOKUP_ELEM cmd is meant) over to use
the callback to simplify and clean up the latter.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25 18:25:37 +02:00
Al Viro
1c0ac5e9bf BACKPORT: fix "netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'"
Descriptor table is a shared object; it's not a place where you can
stick temporary references to files, especially when we don't need
an opened file at all.

Cc: stable@vger.kernel.org # v4.14
Fixes: 98589a0998 ("netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chenbo Feng <fengc@google.com>

Removed the code related to function bpf_prog_get_ok() since it is not
exsit in current android tree.
(cherry picked from commit 040ee69226f8a96b7943645d68f41d5d44b5ff7d)

Change-Id: If7a602128cdea4b4b50c8effb215c9bca7449515
2019-05-17 15:44:06 -07:00
Greg Kroah-Hartman
6c95b90db5 Merge 4.14.79 into android-4.14
Changes in 4.14.79
	xfrm: Validate address prefix lengths in the xfrm selector.
	xfrm6: call kfree_skb when skb is toobig
	xfrm: reset transport header back to network header after all input transforms ahave been applied
	xfrm: reset crypto_done when iterating over multiple input xfrms
	mac80211: Always report TX status
	cfg80211: reg: Init wiphy_idx in regulatory_hint_core()
	mac80211: fix pending queue hang due to TX_DROP
	cfg80211: Address some corner cases in scan result channel updating
	mac80211: TDLS: fix skb queue/priority assignment
	mac80211: fix TX status reporting for ieee80211s
	xfrm: Fix NULL pointer dereference when skb_dst_force clears the dst_entry.
	ARM: 8799/1: mm: fix pci_ioremap_io() offset check
	xfrm: validate template mode
	netfilter: bridge: Don't sabotage nf_hook calls from an l3mdev
	arm64: hugetlb: Fix handling of young ptes
	ARM: dts: BCM63xx: Fix incorrect interrupt specifiers
	net: macb: Clean 64b dma addresses if they are not detected
	soc: fsl: qbman: qman: avoid allocating from non existing gen_pool
	soc: fsl: qe: Fix copy/paste bug in ucc_get_tdm_sync_shift()
	nl80211: Fix possible Spectre-v1 for NL80211_TXRATE_HT
	mac80211_hwsim: do not omit multicast announce of first added radio
	Bluetooth: SMP: fix crash in unpairing
	pxa168fb: prepare the clock
	qed: Avoid implicit enum conversion in qed_set_tunn_cls_info
	qed: Fix mask parameter in qed_vf_prep_tunn_req_tlv
	qed: Avoid implicit enum conversion in qed_roce_mode_to_flavor
	qed: Avoid constant logical operation warning in qed_vf_pf_acquire
	qed: Avoid implicit enum conversion in qed_iwarp_parse_rx_pkt
	nl80211: Fix possible Spectre-v1 for CQM RSSI thresholds
	asix: Check for supported Wake-on-LAN modes
	ax88179_178a: Check for supported Wake-on-LAN modes
	lan78xx: Check for supported Wake-on-LAN modes
	sr9800: Check for supported Wake-on-LAN modes
	r8152: Check for supported Wake-on-LAN Modes
	smsc75xx: Check for Wake-on-LAN modes
	smsc95xx: Check for Wake-on-LAN modes
	cfg80211: fix use-after-free in reg_process_hint()
	perf/core: Fix perf_pmu_unregister() locking
	perf/ring_buffer: Prevent concurent ring buffer access
	perf/x86/intel/uncore: Fix PCI BDF address of M3UPI on SKX
	perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events
	net: fec: fix rare tx timeout
	declance: Fix continuation with the adapter identification message
	net: qualcomm: rmnet: Skip processing loopback packets
	locking/ww_mutex: Fix runtime warning in the WW mutex selftest
	be2net: don't flip hw_features when VXLANs are added/deleted
	net: cxgb3_main: fix a missing-check bug
	yam: fix a missing-check bug
	ocfs2: fix crash in ocfs2_duplicate_clusters_by_page()
	iwlwifi: mvm: check for short GI only for OFDM
	iwlwifi: dbg: allow wrt collection before ALIVE
	iwlwifi: fix the ALIVE notification layout
	tools/testing/nvdimm: unit test clear-error commands
	usbip: vhci_hcd: update 'status' file header and format
	scsi: aacraid: address UBSAN warning regression
	IB/ipoib: Fix lockdep issue found on ipoib_ib_dev_heavy_flush
	IB/rxe: put the pool on allocation failure
	s390/qeth: fix error handling in adapter command callbacks
	net/mlx5: Fix mlx5_get_vector_affinity function
	powerpc/pseries: Add empty update_numa_cpu_lookup_table() for NUMA=n
	dm integrity: fail early if required HMAC key is not available
	net: phy: realtek: Use the dummy stubs for MMD register access for rtl8211b
	net: phy: Add general dummy stubs for MMD register access
	net/mlx5e: Refine ets validation function
	scsi: qla2xxx: Avoid double completion of abort command
	kbuild: set no-integrated-as before incl. arch Makefile
	IB/mlx5: Avoid passing an invalid QP type to firmware
	ARM: tegra: Fix ULPI regression on Tegra20
	l2tp: remove configurable payload offset
	cifs: Use ULL suffix for 64-bit constant
	test_bpf: Fix testing with CONFIG_BPF_JIT_ALWAYS_ON=y on other arches
	KVM: x86: Update the exit_qualification access bits while walking an address
	sparc64: Fix regression in pmdp_invalidate().
	tpm: move the delay_msec increment after sleep in tpm_transmit()
	bpf: sockmap, map_release does not hold refcnt for pinned maps
	tpm: tpm_crb: relinquish locality on error path.
	xen-netfront: Update features after registering netdev
	xen-netfront: Fix mismatched rtnl_unlock
	IB/usnic: Update with bug fixes from core code
	mmc: dw_mmc-rockchip: correct property names in debug
	MIPS: Workaround GCC __builtin_unreachable reordering bug
	lan78xx: Don't reset the interface on open
	enic: do not overwrite error code
	iio: buffer: fix the function signature to match implementation
	selftests/powerpc: Add ptrace hw breakpoint test
	scsi: ibmvfc: Avoid unnecessary port relogin
	scsi: sd: Remember that READ CAPACITY(16) succeeded
	btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf
	net: phy: phylink: Don't release NULL GPIO
	x86/paravirt: Fix some warning messages
	net: stmmac: mark PM functions as __maybe_unused
	kconfig: fix the rule of mainmenu_stmt symbol
	libertas: call into generic suspend code before turning off power
	perf tests: Fix indexing when invoking subtests
	compiler.h: Allow arch-specific asm/compiler.h
	ARM: dts: imx53-qsb: disable 1.2GHz OPP
	perf python: Use -Wno-redundant-decls to build with PYTHON=python3
	rxrpc: Don't check RXRPC_CALL_TX_LAST after calling rxrpc_rotate_tx_window()
	rxrpc: Only take the rwind and mtu values from latest ACK
	rxrpc: Fix connection-level abort handling
	net: ena: fix warning in rmmod caused by double iounmap
	net: ena: fix NULL dereference due to untimely napi initialization
	selftests: rtnetlink.sh explicitly requires bash.
	fs/fat/fatent.c: add cond_resched() to fat_count_free_clusters()
	sch_netem: restore skb->dev after dequeuing from the rbtree
	mtd: spi-nor: Add support for is25wp series chips
	kvm: x86: fix WARN due to uninitialized guest FPU state
	ARM: dts: r8a7790: Correct critical CPU temperature
	media: uvcvideo: Fix driver reference counting
	ALSA: usx2y: Fix invalid stream URBs
	Revert "netfilter: ipv6: nf_defrag: drop skb dst before queueing"
	perf tools: Disable parallelism for 'make clean'
	drm/i915/gvt: fix memory leak of a cmd_entry struct on error exit path
	bridge: do not add port to router list when receives query with source 0.0.0.0
	net: bridge: remove ipv6 zero address check in mcast queries
	ipv6: mcast: fix a use-after-free in inet6_mc_check
	ipv6/ndisc: Preserve IPv6 control buffer if protocol error handlers are called
	llc: set SOCK_RCU_FREE in llc_sap_add_socket()
	net: fec: don't dump RX FIFO register when not available
	net/ipv6: Fix index counter for unicast addresses in in6_dump_addrs
	net: sched: gred: pass the right attribute to gred_change_table_def()
	net: socket: fix a missing-check bug
	net: stmmac: Fix stmmac_mdio_reset() when building stmmac as modules
	net: udp: fix handling of CHECKSUM_COMPLETE packets
	r8169: fix NAPI handling under high load
	sctp: fix race on sctp_id2asoc
	udp6: fix encap return code for resubmitting
	vhost: Fix Spectre V1 vulnerability
	virtio_net: avoid using netif_tx_disable() for serializing tx routine
	ethtool: fix a privilege escalation bug
	bonding: fix length of actor system
	ip6_tunnel: Fix encapsulation layout
	openvswitch: Fix push/pop ethernet validation
	net/mlx5: Take only bit 24-26 of wqe.pftype_wq for page fault type
	net: sched: Fix for duplicate class dump
	net: drop skb on failure in ip_check_defrag()
	net: fix pskb_trim_rcsum_slow() with odd trim offset
	net/mlx5e: fix csum adjustments caused by RXFCS
	rtnetlink: Disallow FDB configuration for non-Ethernet device
	net: ipmr: fix unresolved entry dumps
	net: bcmgenet: Poll internal PHY for GENETv5
	net/sched: cls_api: add missing validation of netlink attributes
	net/mlx5: Fix build break when CONFIG_SMP=n
	Linux 4.14.79

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-11-08 07:43:01 -08:00
John Fastabend
3c0cff34e9 bpf: sockmap, map_release does not hold refcnt for pinned maps
[ Upstream commit ba6b8de423f8d0dee48d6030288ed81c03ddf9f0 ]

Relying on map_release hook to decrement the reference counts when a
map is removed only works if the map is not being pinned. In the
pinned case the ref is decremented immediately and the BPF programs
released. After this BPF programs may not be in-use which is not
what the user would expect.

This patch moves the release logic into bpf_map_put_uref() and brings
sockmap in-line with how a similar case is handled in prog array maps.

Fixes: 3d9e952697de ("bpf: sockmap, fix leaking maps with attached but not detached progs")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-04 14:52:44 +01:00
Dmitry Shmidt
6bbd2da69c ANDROID: Remove duplicate security fix
Merge resolution problem

Change-Id: I763be7d3737179171cab26414dfea8315e5bc655
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
2018-01-31 10:11:29 -08:00
Greg Kroah-Hartman
c3a2eda1e3 Merge 4.14.16 into android-4.14
Changes in 4.14.16
	orangefs: use list_for_each_entry_safe in purge_waiting_ops
	orangefs: initialize op on loop restart in orangefs_devreq_read
	mm, page_alloc: fix potential false positive in __zone_watermark_ok
	netfilter: nfnetlink_cthelper: Add missing permission checks
	netfilter: xt_osf: Add missing permission checks
	xfrm: Fix a race in the xdst pcpu cache.
	Revert "module: Add retpoline tag to VERMAGIC"
	Input: xpad - add support for PDP Xbox One controllers
	Input: trackpoint - force 3 buttons if 0 button is reported
	Input: trackpoint - only expose supported controls for Elan, ALPS and NXP
	Btrfs: fix stale entries in readdir
	KVM: s390: add proper locking for CMMA migration bitmap
	orangefs: fix deadlock; do not write i_size in read_iter
	ARM: net: bpf: avoid 'bx' instruction on non-Thumb capable CPUs
	ARM: net: bpf: fix tail call jumps
	ARM: net: bpf: fix stack alignment
	ARM: net: bpf: move stack documentation
	ARM: net: bpf: correct stack layout documentation
	ARM: net: bpf: fix register saving
	ARM: net: bpf: fix LDX instructions
	ARM: net: bpf: clarify tail_call index
	drm/vc4: Fix NULL pointer dereference in vc4_save_hang_state()
	net: Allow neigh contructor functions ability to modify the primary_key
	ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY
	dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
	ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL
	ipv6: fix udpv6 sendmsg crash caused by too small MTU
	ipv6: ip6_make_skb() needs to clear cork.base.dst
	lan78xx: Fix failure in USB Full Speed
	net: igmp: fix source address check for IGMPv3 reports
	net: qdisc_pkt_len_init() should be more robust
	net: tcp: close sock if net namespace is exiting
	net/tls: Fix inverted error codes to avoid endless loop
	net: vrf: Add support for sends to local broadcast address
	pppoe: take ->needed_headroom of lower device into account on xmit
	r8169: fix memory corruption on retrieval of hardware statistics.
	sctp: do not allow the v4 socket to bind a v4mapped v6 address
	sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbuf
	tipc: fix a memory leak in tipc_nl_node_get_link()
	{net,ib}/mlx5: Don't disable local loopback multicast traffic when needed
	net/mlx5: Fix get vector affinity helper function
	ppp: unlock all_ppp_mutex before registering device
	be2net: restore properly promisc mode after queues reconfiguration
	ip6_gre: init dev->mtu and dev->hard_header_len correctly
	gso: validate gso_type in GSO handlers
	mlxsw: spectrum_router: Don't log an error on missing neighbor
	tun: fix a memory leak for tfile->tx_array
	flow_dissector: properly cap thoff field
	sctp: reinit stream if stream outcnt has been change by sinit in sendmsg
	netlink: extack needs to be reset each time through loop
	net/mlx5e: Fix fixpoint divide exception in mlx5e_am_stats_compare
	nfp: use the correct index for link speed table
	netlink: reset extack earlier in netlink_rcv_skb
	net/tls: Only attach to sockets in ESTABLISHED state
	tls: fix sw_ctx leak
	tls: return -EBUSY if crypto_info is already set
	tls: reset crypto_info when do_tls_setsockopt_tx fails
	net: ipv4: Make "ip route get" match iif lo rules again.
	vmxnet3: repair memory leak
	perf/x86/amd/power: Do not load AMD power module on !AMD platforms
	x86/microcode/intel: Extend BDW late-loading further with LLC size check
	x86/microcode: Fix again accessing initrd after having been freed
	x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems
	hrtimer: Reset hrtimer cpu base proper on CPU hotplug
	bpf: introduce BPF_JIT_ALWAYS_ON config
	bpf: avoid false sharing of map refcount with max_entries
	bpf: fix divides by zero
	bpf: fix 32-bit divide by zero
	bpf: reject stores into ctx via st and xadd
	bpf, arm64: fix stack_depth tracking in combination with tail calls
	cpufreq: governor: Ensure sufficiently large sampling intervals
	nfsd: auth: Fix gid sorting when rootsquash enabled
	Linux 4.14.16

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-01-31 14:23:18 +01:00
Daniel Borkmann
3ea4247ec1 bpf: avoid false sharing of map refcount with max_entries
[ upstream commit be95a845cc4402272994ce290e3ad928aff06cb9 ]

In addition to commit b2157399cc98 ("bpf: prevent out-of-bounds
speculation") also change the layout of struct bpf_map such that
false sharing of fast-path members like max_entries is avoided
when the maps reference counter is altered. Therefore enforce
them to be placed into separate cachelines.

pahole dump after change:

  struct bpf_map {
        const struct bpf_map_ops  * ops;                 /*     0     8 */
        struct bpf_map *           inner_map_meta;       /*     8     8 */
        void *                     security;             /*    16     8 */
        enum bpf_map_type          map_type;             /*    24     4 */
        u32                        key_size;             /*    28     4 */
        u32                        value_size;           /*    32     4 */
        u32                        max_entries;          /*    36     4 */
        u32                        map_flags;            /*    40     4 */
        u32                        pages;                /*    44     4 */
        u32                        id;                   /*    48     4 */
        int                        numa_node;            /*    52     4 */
        bool                       unpriv_array;         /*    56     1 */

        /* XXX 7 bytes hole, try to pack */

        /* --- cacheline 1 boundary (64 bytes) --- */
        struct user_struct *       user;                 /*    64     8 */
        atomic_t                   refcnt;               /*    72     4 */
        atomic_t                   usercnt;              /*    76     4 */
        struct work_struct         work;                 /*    80    32 */
        char                       name[16];             /*   112    16 */
        /* --- cacheline 2 boundary (128 bytes) --- */

        /* size: 128, cachelines: 2, members: 17 */
        /* sum members: 121, holes: 1, sum holes: 7 */
  };

Now all entries in the first cacheline are read only throughout
the life time of the map, set up once during map creation. Overall
struct size and number of cachelines doesn't change from the
reordering. struct bpf_map is usually first member and embedded
in map structs in specific map implementations, so also avoid those
members to sit at the end where it could potentially share the
cacheline with first map values e.g. in the array since remote
CPUs could trigger map updates just as well for those (easily
dirtying members like max_entries intentionally as well) while
having subsequent values in cache.

Quoting from Google's Project Zero blog [1]:

  Additionally, at least on the Intel machine on which this was
  tested, bouncing modified cache lines between cores is slow,
  apparently because the MESI protocol is used for cache coherence
  [8]. Changing the reference counter of an eBPF array on one
  physical CPU core causes the cache line containing the reference
  counter to be bounced over to that CPU core, making reads of the
  reference counter on all other CPU cores slow until the changed
  reference counter has been written back to memory. Because the
  length and the reference counter of an eBPF array are stored in
  the same cache line, this also means that changing the reference
  counter on one physical CPU core causes reads of the eBPF array's
  length to be slow on other physical CPU cores (intentional false
  sharing).

While this doesn't 'control' the out-of-bounds speculation through
masking the index as in commit b2157399cc98, triggering a manipulation
of the map's reference counter is really trivial, so lets not allow
to easily affect max_entries from it.

Splitting to separate cachelines also generally makes sense from
a performance perspective anyway in that fast-path won't have a
cache miss if the map gets pinned, reused in other progs, etc out
of control path, thus also avoids unintentional false sharing.

  [1] https://googleprojectzero.blogspot.ch/2018/01/reading-privileged-memory-with-side.html

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31 14:03:50 +01:00
Greg Kroah-Hartman
9b68347c35 Merge 4.14.14 into android-4.14
Changes in 4.14.14
	dm bufio: fix shrinker scans when (nr_to_scan < retain_target)
	KVM: Fix stack-out-of-bounds read in write_mmio
	can: vxcan: improve handling of missing peer name attribute
	can: gs_usb: fix return value of the "set_bittiming" callback
	IB/srpt: Disable RDMA access by the initiator
	IB/srpt: Fix ACL lookup during login
	MIPS: Validate PR_SET_FP_MODE prctl(2) requests against the ABI of the task
	MIPS: Factor out NT_PRFPREG regset access helpers
	MIPS: Guard against any partial write attempt with PTRACE_SETREGSET
	MIPS: Consistently handle buffer counter with PTRACE_SETREGSET
	MIPS: Fix an FCSR access API regression with NT_PRFPREG and MSA
	MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET
	MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses
	cgroup: fix css_task_iter crash on CSS_TASK_ITER_PROC
	kvm: vmx: Scrub hardware GPRs at VM-exit
	platform/x86: wmi: Call acpi_wmi_init() later
	iw_cxgb4: only call the cq comp_handler when the cq is armed
	iw_cxgb4: atomically flush the qp
	iw_cxgb4: only clear the ARMED bit if a notification is needed
	iw_cxgb4: reflect the original WR opcode in drain cqes
	iw_cxgb4: when flushing, complete all wrs in a chain
	x86/acpi: Handle SCI interrupts above legacy space gracefully
	ALSA: pcm: Remove incorrect snd_BUG_ON() usages
	ALSA: pcm: Workaround for weird PulseAudio behavior on rewind error
	ALSA: pcm: Add missing error checks in OSS emulation plugin builder
	ALSA: pcm: Abort properly at pending signal in OSS read/write loops
	ALSA: pcm: Allow aborting mutex lock at OSS read/write loops
	ALSA: aloop: Release cable upon open error path
	ALSA: aloop: Fix inconsistent format due to incomplete rule
	ALSA: aloop: Fix racy hw constraints adjustment
	x86/acpi: Reduce code duplication in mp_override_legacy_irq()
	8021q: fix a memory leak for VLAN 0 device
	ip6_tunnel: disable dst caching if tunnel is dual-stack
	net: core: fix module type in sock_diag_bind
	phylink: ensure we report link down when LOS asserted
	RDS: Heap OOB write in rds_message_alloc_sgs()
	RDS: null pointer dereference in rds_atomic_free_op
	net: fec: restore dev_id in the cases of probe error
	net: fec: defer probe if regulator is not ready
	net: fec: free/restore resource in related probe error pathes
	sctp: do not retransmit upon FragNeeded if PMTU discovery is disabled
	sctp: fix the handling of ICMP Frag Needed for too small MTUs
	sh_eth: fix TSU resource handling
	net: stmmac: enable EEE in MII, GMII or RGMII only
	sh_eth: fix SH7757 GEther initialization
	ipv6: fix possible mem leaks in ipv6_make_skb()
	ethtool: do not print warning for applications using legacy API
	mlxsw: spectrum_router: Fix NULL pointer deref
	net/sched: Fix update of lastuse in act modules implementing stats_update
	ipv6: sr: fix TLVs not being copied using setsockopt
	mlxsw: spectrum: Relax sanity checks during enslavement
	sfp: fix sfp-bus oops when removing socket/upstream
	membarrier: Disable preemption when calling smp_call_function_many()
	crypto: algapi - fix NULL dereference in crypto_remove_spawns()
	mmc: renesas_sdhi: Add MODULE_LICENSE
	rbd: reacquire lock should update lock owner client id
	rbd: set max_segments to USHRT_MAX
	iwlwifi: pcie: fix DMA memory mapping / unmapping
	x86/microcode/intel: Extend BDW late-loading with a revision check
	KVM: x86: Add memory barrier on vmcs field lookup
	KVM: PPC: Book3S PR: Fix WIMG handling under pHyp
	KVM: PPC: Book3S HV: Drop prepare_done from struct kvm_resize_hpt
	KVM: PPC: Book3S HV: Fix use after free in case of multiple resize requests
	KVM: PPC: Book3S HV: Always flush TLB in kvmppc_alloc_reset_hpt()
	drm/vmwgfx: Don't cache framebuffer maps
	drm/vmwgfx: Potential off by one in vmw_view_add()
	drm/i915/gvt: Clear the shadow page table entry after post-sync
	drm/i915: Whitelist SLICE_COMMON_ECO_CHICKEN1 on Geminilake.
	drm/i915: Move init_clock_gating() back to where it was
	drm/i915: Fix init_clock_gating for resume
	bpf: prevent out-of-bounds speculation
	bpf, array: fix overflow in max_entries and undefined behavior in index_mask
	bpf: arsh is not supported in 32 bit alu thus reject it
	USB: serial: cp210x: add IDs for LifeScan OneTouch Verio IQ
	USB: serial: cp210x: add new device ID ELV ALC 8xxx
	usb: misc: usb3503: make sure reset is low for at least 100us
	USB: fix usbmon BUG trigger
	USB: UDC core: fix double-free in usb_add_gadget_udc_release
	usbip: remove kernel addresses from usb device and urb debug msgs
	usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input
	usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer
	staging: android: ashmem: fix a race condition in ASHMEM_SET_SIZE ioctl
	Bluetooth: Prevent stack info leak from the EFS element.
	uas: ignore UAS for Norelsys NS1068(X) chips
	mux: core: fix double get_device()
	kdump: write correct address of mem_section into vmcoreinfo
	apparmor: fix ptrace label match when matching stacked labels
	e1000e: Fix e1000_check_for_copper_link_ich8lan return value.
	x86/pti: Unbreak EFI old_memmap
	x86/Documentation: Add PTI description
	x86/cpufeatures: Add X86_BUG_SPECTRE_V[12]
	sysfs/cpu: Add vulnerability folder
	x86/cpu: Implement CPU vulnerabilites sysfs functions
	x86/tboot: Unbreak tboot with PTI enabled
	x86/mm/pti: Remove dead logic in pti_user_pagetable_walk*()
	x86/cpu/AMD: Make LFENCE a serializing instruction
	x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
	sysfs/cpu: Fix typos in vulnerability documentation
	x86/alternatives: Fix optimize_nops() checking
	x86/pti: Make unpoison of pgd for trusted boot work for real
	objtool: Detect jumps to retpoline thunks
	objtool: Allow alternatives to be ignored
	x86/retpoline: Add initial retpoline support
	x86/spectre: Add boot time option to select Spectre v2 mitigation
	x86/retpoline/crypto: Convert crypto assembler indirect jumps
	x86/retpoline/entry: Convert entry assembler indirect jumps
	x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
	x86/retpoline/hyperv: Convert assembler indirect jumps
	x86/retpoline/xen: Convert Xen hypercall indirect jumps
	x86/retpoline/checksum32: Convert assembler indirect jumps
	x86/retpoline/irq32: Convert assembler indirect jumps
	x86/retpoline: Fill return stack buffer on vmexit
	selftests/x86: Add test_vsyscall
	x86/pti: Fix !PCID and sanitize defines
	security/Kconfig: Correct the Documentation reference for PTI
	x86,perf: Disable intel_bts when PTI
	x86/retpoline: Remove compile time warning
	Linux 4.14.14

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-01-17 10:33:24 +01:00
Alexei Starovoitov
a5dbaf8768 bpf: prevent out-of-bounds speculation
commit b2157399cc9898260d6031c5bfe45fe137c1fbe7 upstream.

Under speculation, CPUs may mis-predict branches in bounds checks. Thus,
memory accesses under a bounds check may be speculated even if the
bounds check fails, providing a primitive for building a side channel.

To avoid leaking kernel data round up array-based maps and mask the index
after bounds check, so speculated load with out of bounds index will load
either valid value from the array or zero from the padded area.

Unconditionally mask index for all array types even when max_entries
are not rounded to power of 2 for root user.
When map is created by unpriv user generate a sequence of bpf insns
that includes AND operation to make sure that JITed code includes
the same 'index & index_mask' operation.

If prog_array map is created by unpriv user replace
  bpf_tail_call(ctx, map, index);
with
  if (index >= max_entries) {
    index &= map->index_mask;
    bpf_tail_call(ctx, map, index);
  }
(along with roundup to power 2) to prevent out-of-bounds speculation.
There is secondary redundant 'if (index >= max_entries)' in the interpreter
and in all JITs, but they can be optimized later if necessary.

Other array-like maps (cpumap, devmap, sockmap, perf_event_array, cgroup_array)
cannot be used by unpriv, so no changes there.

That fixes bpf side of "Variant 1: bounds check bypass (CVE-2017-5753)" on
all architectures with and without JIT.

v2->v3:
Daniel noticed that attack potentially can be crafted via syscall commands
without loading the program, so add masking to those paths as well.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-17 09:45:25 +01:00
Chenbo Feng
02afae7216 BACKPORT: selinux: bpf: Add addtional check for bpf object file receive
Introduce a bpf object related check when sending and receiving files
through unix domain socket as well as binder. It checks if the receiving
process have privilege to read/write the bpf map or use the bpf program.
This check is necessary because the bpf maps and programs are using a
anonymous inode as their shared inode so the normal way of checking the
files and sockets when passing between processes cannot work properly on
eBPF object. This check only works when the BPF_SYSCALL is configured.

Signed-off-by: Chenbo Feng <fengc@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Bug: 30950746
Change-Id: I5b2cf4ccb4eab7eda91ddd7091d6aa3e7ed9f2cd

(cherry picked from commit f66e448cfda021b0bcd884f26709796fe19c7cc1)
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2017-12-18 21:11:22 +05:30
Chenbo Feng
3479b1366c BACKPORT: security: bpf: Add LSM hooks for bpf object related syscall
Introduce several LSM hooks for the syscalls that will allow the
userspace to access to eBPF object such as eBPF programs and eBPF maps.
The security check is aimed to enforce a per object security protection
for eBPF object so only processes with the right priviliges can
read/write to a specific map or use a specific eBPF program. Besides
that, a general security hook is added before the multiplexer of bpf
syscall to check the cmd and the attribute used for the command. The
actual security module can decide which command need to be checked and
how the cmd should be checked.

Signed-off-by: Chenbo Feng <fengc@google.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Bug: 30950746
Change-Id: Ieb3ac74392f531735fc7c949b83346a5f587a77b

(cherry picked from commit afdb09c720b62b8090584c11151d856df330e57d)
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2017-12-18 21:11:22 +05:30
Chenbo Feng
cace572e16 BACKPORT: bpf: Add file mode configuration into bpf maps
Introduce the map read/write flags to the eBPF syscalls that returns the
map fd. The flags is used to set up the file mode when construct a new
file descriptor for bpf maps. To not break the backward capability, the
f_flags is set to O_RDWR if the flag passed by syscall is 0. Otherwise
it should be O_RDONLY or O_WRONLY. When the userspace want to modify or
read the map content, it will check the file mode to see if it is
allowed to make the change.

Signed-off-by: Chenbo Feng <fengc@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Bug: 30950746
Change-Id: Icfad20f1abb77f91068d244fb0d87fa40824dd1b

(cherry picked from commit 6e71b04a82248ccf13a94b85cbc674a9fefe53f5)
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2017-12-18 21:11:22 +05:30
Shmulik Ladkani
98589a0998 netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'
Commit 2c16d60332 ("netfilter: xt_bpf: support ebpf") introduced
support for attaching an eBPF object by an fd, with the
'bpf_mt_check_v1' ABI expecting the '.fd' to be specified upon each
IPT_SO_SET_REPLACE call.

However this breaks subsequent iptables calls:

 # iptables -A INPUT -m bpf --object-pinned /sys/fs/bpf/xxx -j ACCEPT
 # iptables -A INPUT -s 5.6.7.8 -j ACCEPT
 iptables: Invalid argument. Run `dmesg' for more information.

That's because iptables works by loading existing rules using
IPT_SO_GET_ENTRIES to userspace, then issuing IPT_SO_SET_REPLACE with
the replacement set.

However, the loaded 'xt_bpf_info_v1' has an arbitrary '.fd' number
(from the initial "iptables -m bpf" invocation) - so when 2nd invocation
occurs, userspace passes a bogus fd number, which leads to
'bpf_mt_check_v1' to fail.

One suggested solution [1] was to hack iptables userspace, to perform a
"entries fixup" immediatley after IPT_SO_GET_ENTRIES, by opening a new,
process-local fd per every 'xt_bpf_info_v1' entry seen.

However, in [2] both Pablo Neira Ayuso and Willem de Bruijn suggested to
depricate the xt_bpf_info_v1 ABI dealing with pinned ebpf objects.

This fix changes the XT_BPF_MODE_FD_PINNED behavior to ignore the given
'.fd' and instead perform an in-kernel lookup for the bpf object given
the provided '.path'.

It also defines an alias for the XT_BPF_MODE_FD_PINNED mode, named
XT_BPF_MODE_PATH_PINNED, to better reflect the fact that the user is
expected to provide the path of the pinned object.

Existing XT_BPF_MODE_FD_ELF behavior (non-pinned fd mode) is preserved.

References: [1] https://marc.info/?l=netfilter-devel&m=150564724607440&w=2
            [2] https://marc.info/?l=netfilter-devel&m=150575727129880&w=2

Reported-by: Rafael Buchbinder <rafi@rbk.ms>
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-09 15:18:04 +02:00
John Fastabend
5a67da2a71 bpf: add support for sockmap detach programs
The bpf map sockmap supports adding programs via attach commands. This
patch adds the detach command to keep the API symmetric and allow
users to remove previously added programs. Otherwise the user would
have to delete the map and re-add it to get in this state.

This also adds a series of additional tests to capture detach operation
and also attaching/detaching invalid prog types.

API note: socks will run (or not run) programs depending on the state
of the map at the time the sock is added. We do not for example walk
the map and remove programs from previously attached socks.

Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 21:11:00 -07:00
John Fastabend
464bc0fd62 bpf: convert sockmap field attach_bpf_fd2 to type
In the initial sockmap API we provided strparser and verdict programs
using a single attach command by extending the attach API with a the
attach_bpf_fd2 field.

However, if we add other programs in the future we will be adding a
field for every new possible type, attach_bpf_fd(3,4,..). This
seems a bit clumsy for an API. So lets push the programs using two
new type fields.

   BPF_SK_SKB_STREAM_PARSER
   BPF_SK_SKB_STREAM_VERDICT

This has the advantage of having a readable name and can easily be
extended in the future.

Updates to samples and sockmap included here also generalize tests
slightly to support upcoming patch for multiple map support.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Fixes: 174a79ff95 ("bpf: sockmap with sk redirect support")
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-28 11:13:21 -07:00
David S. Miller
d6e1e46f69 bpf: linux/bpf.h needs linux/numa.h
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-19 23:34:03 -07:00
Martin KaFai Lau
96eabe7a40 bpf: Allow selecting numa node during map creation
The current map creation API does not allow to provide the numa-node
preference.  The memory usually comes from where the map-creation-process
is running.  The performance is not ideal if the bpf_prog is known to
always run in a numa node different from the map-creation-process.

One of the use case is sharding on CPU to different LRU maps (i.e.
an array of LRU maps).  Here is the test result of map_perf_test on
the INNER_LRU_HASH_PREALLOC test if we force the lru map used by
CPU0 to be allocated from a remote numa node:

[ The machine has 20 cores. CPU0-9 at node 0. CPU10-19 at node 1 ]

># taskset -c 10 ./map_perf_test 512 8 1260000 8000000
5:inner_lru_hash_map_perf pre-alloc 1628380 events per sec
4:inner_lru_hash_map_perf pre-alloc 1626396 events per sec
3:inner_lru_hash_map_perf pre-alloc 1626144 events per sec
6:inner_lru_hash_map_perf pre-alloc 1621657 events per sec
2:inner_lru_hash_map_perf pre-alloc 1621534 events per sec
1:inner_lru_hash_map_perf pre-alloc 1620292 events per sec
7:inner_lru_hash_map_perf pre-alloc 1613305 events per sec
0:inner_lru_hash_map_perf pre-alloc 1239150 events per sec  #<<<

After specifying numa node:
># taskset -c 10 ./map_perf_test 512 8 1260000 8000000
5:inner_lru_hash_map_perf pre-alloc 1629627 events per sec
3:inner_lru_hash_map_perf pre-alloc 1628057 events per sec
1:inner_lru_hash_map_perf pre-alloc 1623054 events per sec
6:inner_lru_hash_map_perf pre-alloc 1616033 events per sec
2:inner_lru_hash_map_perf pre-alloc 1614630 events per sec
4:inner_lru_hash_map_perf pre-alloc 1612651 events per sec
7:inner_lru_hash_map_perf pre-alloc 1609337 events per sec
0:inner_lru_hash_map_perf pre-alloc 1619340 events per sec #<<<

This patch adds one field, numa_node, to the bpf_attr.  Since numa node 0
is a valid node, a new flag BPF_F_NUMA_NODE is also added.  The numa_node
field is honored if and only if the BPF_F_NUMA_NODE flag is set.

Numa node selection is not supported for percpu map.

This patch does not change all the kmalloc.  F.e.
'htab = kzalloc()' is not changed since the object
is small enough to stay in the cache.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-19 21:35:43 -07:00
John Fastabend
6bdc9c4c31 bpf: sock_map fixes for !CONFIG_BPF_SYSCALL and !STREAM_PARSER
Resolve issues with !CONFIG_BPF_SYSCALL and !STREAM_PARSER

net/core/filter.c: In function ‘do_sk_redirect_map’:
net/core/filter.c:1881:3: error: implicit declaration of function ‘__sock_map_lookup_elem’ [-Werror=implicit-function-declaration]
   sk = __sock_map_lookup_elem(ri->map, ri->ifindex);
   ^
net/core/filter.c:1881:6: warning: assignment makes pointer from integer without a cast [enabled by default]
   sk = __sock_map_lookup_elem(ri->map, ri->ifindex);

Fixes: 174a79ff95 ("bpf: sockmap with sk redirect support")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16 15:34:13 -07:00
John Fastabend
174a79ff95 bpf: sockmap with sk redirect support
Recently we added a new map type called dev map used to forward XDP
packets between ports (6093ec2dc3). This patches introduces a
similar notion for sockets.

A sockmap allows users to add participating sockets to a map. When
sockets are added to the map enough context is stored with the
map entry to use the entry with a new helper

  bpf_sk_redirect_map(map, key, flags)

This helper (analogous to bpf_redirect_map in XDP) is given the map
and an entry in the map. When called from a sockmap program, discussed
below, the skb will be sent on the socket using skb_send_sock().

With the above we need a bpf program to call the helper from that will
then implement the send logic. The initial site implemented in this
series is the recv_sock hook. For this to work we implemented a map
attach command to add attributes to a map. In sockmap we add two
programs a parse program and a verdict program. The parse program
uses strparser to build messages and pass them to the verdict program.
The parse programs use the normal strparser semantics. The verdict
program is of type SK_SKB.

The verdict program returns a verdict SK_DROP, or  SK_REDIRECT for
now. Additional actions may be added later. When SK_REDIRECT is
returned, expected when bpf program uses bpf_sk_redirect_map(), the
sockmap logic will consult per cpu variables set by the helper routine
and pull the sock entry out of the sock map. This pattern follows the
existing redirect logic in cls and xdp programs.

This gives the flow,

 recv_sock -> str_parser (parse_prog) -> verdict_prog -> skb_send_sock
                                                     \
                                                      -> kfree_skb

As an example use case a message based load balancer may use specific
logic in the verdict program to select the sock to send on.

Sample programs are provided in future patches that hopefully illustrate
the user interfaces. Also selftests are in follow-on patches.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16 11:27:53 -07:00
John Fastabend
a6f6df69c4 bpf: export bpf_prog_inc_not_zero
bpf_prog_inc_not_zero will be used by upcoming sockmap patches this
patch simply exports it so we can pull it in.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16 11:27:53 -07:00
Edward Cree
f1174f77b5 bpf/verifier: rework value tracking
Unifies adjusted and unadjusted register value types (e.g. FRAME_POINTER is
 now just a PTR_TO_STACK with zero offset).
Tracks value alignment by means of tracking known & unknown bits.  This
 also replaces the 'reg->imm' (leading zero bits) calculations for (what
 were) UNKNOWN_VALUEs.
If pointer leaks are allowed, and adjust_ptr_min_max_vals returns -EACCES,
 treat the pointer as an unknown scalar and try again, because we might be
 able to conclude something about the result (e.g. pointer & 0x40 is either
 0 or 0x40).
Verifier hooks in the netronome/nfp driver were changed to match the new
 data structures.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-08 17:51:34 -07:00
John Fastabend
46f55cffa4 net: fix build error in devmap helper calls
Initial patches missed case with CONFIG_BPF_SYSCALL not set.

Fixes: 11393cc9b9 ("xdp: Add batching support to redirect map")
Fixes: 97f91a7cf0 ("bpf: add bpf_redirect_map helper routine")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17 21:58:32 -07:00
John Fastabend
11393cc9b9 xdp: Add batching support to redirect map
For performance reasons we want to avoid updating the tail pointer in
the driver tx ring as much as possible. To accomplish this we add
batching support to the redirect path in XDP.

This adds another ndo op "xdp_flush" that is used to inform the driver
that it should bump the tail pointer on the TX ring.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17 09:48:06 -07:00
John Fastabend
97f91a7cf0 bpf: add bpf_redirect_map helper routine
BPF programs can use the devmap with a bpf_redirect_map() helper
routine to forward packets to netdevice in map.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17 09:48:06 -07:00
Daniel Borkmann
f96da09473 bpf: simplify narrower ctx access
This work tries to make the semantics and code around the
narrower ctx access a bit easier to follow. Right now
everything is done inside the .is_valid_access(). Offset
matching is done differently for read/write types, meaning
writes don't support narrower access and thus matching only
on offsetof(struct foo, bar) is enough whereas for read
case that supports narrower access we must check for
offsetof(struct foo, bar) + offsetof(struct foo, bar) +
sizeof(<bar>) - 1 for each of the cases. For read cases of
individual members that don't support narrower access (like
packet pointers or skb->cb[] case which has its own narrow
access logic), we check as usual only offsetof(struct foo,
bar) like in write case. Then, for the case where narrower
access is allowed, we also need to set the aux info for the
access. Meaning, ctx_field_size and converted_op_size have
to be set. First is the original field size e.g. sizeof(<bar>)
as in above example from the user facing ctx, and latter
one is the target size after actual rewrite happened, thus
for the kernel facing ctx. Also here we need the range match
and we need to keep track changing convert_ctx_access() and
converted_op_size from is_valid_access() as both are not at
the same location.

We can simplify the code a bit: check_ctx_access() becomes
simpler in that we only store ctx_field_size as a meta data
and later in convert_ctx_accesses() we fetch the target_size
right from the location where we do convert. Should the verifier
be misconfigured we do reject for BPF_WRITE cases or target_size
that are not provided. For the subsystems, we always work on
ranges in is_valid_access() and add small helpers for ranges
and narrow access, convert_ctx_accesses() sets target_size
for the relevant instruction.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Cc: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-03 02:22:52 -07:00
Martin KaFai Lau
14dc6f04f4 bpf: Add syscall lookup support for fd array and htab
This patch allows userspace to do BPF_MAP_LOOKUP_ELEM on
BPF_MAP_TYPE_PROG_ARRAY,
BPF_MAP_TYPE_ARRAY_OF_MAPS and
BPF_MAP_TYPE_HASH_OF_MAPS.

The lookup returns a prog-id or map-id to the userspace.
The userspace can then use the BPF_PROG_GET_FD_BY_ID
or BPF_MAP_GET_FD_BY_ID to get a fd.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-29 13:13:25 -04:00
Yonghong Song
239946314e bpf: possibly avoid extra masking for narrower load in verifier
Commit 31fd85816d ("bpf: permits narrower load from bpf program
context fields") permits narrower load for certain ctx fields.
The commit however will already generate a masking even if
the prog-specific ctx conversion produces the result with
narrower size.

For example, for __sk_buff->protocol, the ctx conversion
loads the data into register with 2-byte load.
A narrower 2-byte load should not generate masking.
For __sk_buff->vlan_present, the conversion function
set the result as either 0 or 1, essentially a byte.
The narrower 2-byte or 1-byte load should not generate masking.

To avoid unnecessary masking, prog-specific *_is_valid_access
now passes converted_op_size back to verifier, which indicates
the valid data width after perceived future conversion.
Based on this information, verifier is able to avoid
unnecessary marking.

Since we want more information back from prog-specific
*_is_valid_access checking, all of them are packed into
one data structure for more clarity.

Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-23 14:04:11 -04:00
Yonghong Song
31fd85816d bpf: permits narrower load from bpf program context fields
Currently, verifier will reject a program if it contains an
narrower load from the bpf context structure. For example,
        __u8 h = __sk_buff->hash, or
        __u16 p = __sk_buff->protocol
        __u32 sample_period = bpf_perf_event_data->sample_period
which are narrower loads of 4-byte or 8-byte field.

This patch solves the issue by:
  . Introduce a new parameter ctx_field_size to carry the
    field size of narrower load from prog type
    specific *__is_valid_access validator back to verifier.
  . The non-zero ctx_field_size for a memory access indicates
    (1). underlying prog type specific convert_ctx_accesses
         supporting non-whole-field access
    (2). the current insn is a narrower or whole field access.
  . In verifier, for such loads where load memory size is
    less than ctx_field_size, verifier transforms it
    to a full field load followed by proper masking.
  . Currently, __sk_buff and bpf_perf_event_data->sample_period
    are supporting narrowing loads.
  . Narrower stores are still not allowed as typical ctx stores
    are just normal stores.

Because of this change, some tests in verifier will fail and
these tests are removed. As a bonus, rename some out of bound
__sk_buff->cb access to proper field name and remove two
redundant "skb cb oob" tests.

Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-14 14:56:25 -04:00
Martin KaFai Lau
f3f1c054c2 bpf: Introduce bpf_map ID
This patch generates an unique ID for each created bpf_map.
The approach is similar to the earlier patch for bpf_prog ID.

It is worth to note that the bpf_map's ID and bpf_prog's ID
are in two independent ID spaces and both have the same valid range:
[1, INT_MAX).

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06 15:41:22 -04:00
Martin KaFai Lau
dc4bb0e235 bpf: Introduce bpf_prog ID
This patch generates an unique ID for each BPF_PROG_LOAD-ed prog.
It is worth to note that each BPF_PROG_LOAD-ed prog will have
a different ID even they have the same bpf instructions.

The ID is generated by the existing idr_alloc_cyclic().
The ID is ranged from [1, INT_MAX).  It is allocated in cyclic manner,
so an ID will get reused every 2 billion BPF_PROG_LOAD.

The bpf_prog_alloc_id() is done after bpf_prog_select_runtime()
because the jit process may have allocated a new prog.  Hence,
we need to ensure the value of pointer 'prog' will not be changed
any more before storing the prog to the prog_idr.

After bpf_prog_select_runtime(), the prog is read-only.  Hence,
the id is stored in 'struct bpf_prog_aux'.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06 15:41:22 -04:00
Alexei Starovoitov
8726679a0f bpf: teach verifier to track stack depth
teach verifier to track bpf program stack depth

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-31 19:29:47 -04:00
Johannes Berg
40077e0cf6 bpf: remove struct bpf_map_type_list
There's no need to have struct bpf_map_type_list since
it just contains a list_head, the type, and the ops
pointer. Since the types are densely packed and not
actually dynamically registered, it's much easier and
smaller to have an array of type->ops pointer. Also
initialize this array statically to remove code needed
to initialize it.

In order to save duplicating the list, move it to the
types header file added by the previous patch and
include it in the same fashion.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-11 14:38:43 -04:00
Johannes Berg
be9370a7d8 bpf: remove struct bpf_prog_type_list
There's no need to have struct bpf_prog_type_list since
it just contains a list_head, the type, and the ops
pointer. Since the types are densely packed and not
actually dynamically registered, it's much easier and
smaller to have an array of type->ops pointer. Also
initialize this array statically to remove code needed
to initialize it.

In order to save duplicating the list, move it to a new
header file and include it in the places needing it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-11 14:38:43 -04:00
Alexei Starovoitov
1cf1cae963 bpf: introduce BPF_PROG_TEST_RUN command
development and testing of networking bpf programs is quite cumbersome.
Despite availability of user space bpf interpreters the kernel is
the ultimate authority and execution environment.
Current test frameworks for TC include creation of netns, veth,
qdiscs and use of various packet generators just to test functionality
of a bpf program. XDP testing is even more complicated, since
qemu needs to be started with gro/gso disabled and precise queue
configuration, transferring of xdp program from host into guest,
attaching to virtio/eth0 and generating traffic from the host
while capturing the results from the guest.

Moreover analyzing performance bottlenecks in XDP program is
impossible in virtio environment, since cost of running the program
is tiny comparing to the overhead of virtio packet processing,
so performance testing can only be done on physical nic
with another server generating traffic.

Furthermore ongoing changes to user space control plane of production
applications cannot be run on the test servers leaving bpf programs
stubbed out for testing.

Last but not least, the upstream llvm changes are validated by the bpf
backend testsuite which has no ability to test the code generated.

To improve this situation introduce BPF_PROG_TEST_RUN command
to test and performance benchmark bpf programs.

Joint work with Daniel Borkmann.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-01 12:45:57 -07:00
Martin KaFai Lau
bcc6b1b7eb bpf: Add hash of maps support
This patch adds hash of maps support (hashmap->bpf_map).
BPF_MAP_TYPE_HASH_OF_MAPS is added.

A map-in-map contains a pointer to another map and lets call
this pointer 'inner_map_ptr'.

Notes on deleting inner_map_ptr from a hash map:

1. For BPF_F_NO_PREALLOC map-in-map, when deleting
   an inner_map_ptr, the htab_elem itself will go through
   a rcu grace period and the inner_map_ptr resides
   in the htab_elem.

2. For pre-allocated htab_elem (!BPF_F_NO_PREALLOC),
   when deleting an inner_map_ptr, the htab_elem may
   get reused immediately.  This situation is similar
   to the existing prealloc-ated use cases.

   However, the bpf_map_fd_put_ptr() calls bpf_map_put() which calls
   inner_map->ops->map_free(inner_map) which will go
   through a rcu grace period (i.e. all bpf_map's map_free
   currently goes through a rcu grace period).  Hence,
   the inner_map_ptr is still safe for the rcu reader side.

This patch also includes BPF_MAP_TYPE_HASH_OF_MAPS to the
check_map_prealloc() in the verifier.  preallocation is a
must for BPF_PROG_TYPE_PERF_EVENT.  Hence, even we don't expect
heavy updates to map-in-map, enforcing BPF_F_NO_PREALLOC for map-in-map
is impossible without disallowing BPF_PROG_TYPE_PERF_EVENT from using
map-in-map first.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 15:45:45 -07:00
Martin KaFai Lau
56f668dfe0 bpf: Add array of maps support
This patch adds a few helper funcs to enable map-in-map
support (i.e. outer_map->inner_map).  The first outer_map type
BPF_MAP_TYPE_ARRAY_OF_MAPS is also added in this patch.
The next patch will introduce a hash of maps type.

Any bpf map type can be acted as an inner_map.  The exception
is BPF_MAP_TYPE_PROG_ARRAY because the extra level of
indirection makes it harder to verify the owner_prog_type
and owner_jited.

Multi-level map-in-map is not supported (i.e. map->map is ok
but not map->map->map).

When adding an inner_map to an outer_map, it currently checks the
map_type, key_size, value_size, map_flags, max_entries and ops.
The verifier also uses those map's properties to do static analysis.
map_flags is needed because we need to ensure BPF_PROG_TYPE_PERF_EVENT
is using a preallocated hashtab for the inner_hash also.  ops and
max_entries are needed to generate inlined map-lookup instructions.
For simplicity reason, a simple '==' test is used for both map_flags
and max_entries.  The equality of ops is implied by the equality of
map_type.

During outer_map creation time, an inner_map_fd is needed to create an
outer_map.  However, the inner_map_fd's life time does not depend on the
outer_map.  The inner_map_fd is merely used to initialize
the inner_map_meta of the outer_map.

Also, for the outer_map:

* It allows element update and delete from syscall
* It allows element lookup from bpf_prog

The above is similar to the current fd_array pattern.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 15:45:45 -07:00
Alexei Starovoitov
81ed18ab30 bpf: add helper inlining infra and optimize map_array lookup
Optimize bpf_call -> bpf_map_lookup_elem() -> array_map_lookup_elem()
into a sequence of bpf instructions.
When JIT is on the sequence of bpf instructions is the sequence
of native cpu instructions with significantly faster performance
than indirect call and two function's prologue/epilogue.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16 20:44:11 -07:00
Daniel Borkmann
74451e66d5 bpf: make jited programs visible in traces
Long standing issue with JITed programs is that stack traces from
function tracing check whether a given address is kernel code
through {__,}kernel_text_address(), which checks for code in core
kernel, modules and dynamically allocated ftrace trampolines. But
what is still missing is BPF JITed programs (interpreted programs
are not an issue as __bpf_prog_run() will be attributed to them),
thus when a stack trace is triggered, the code walking the stack
won't see any of the JITed ones. The same for address correlation
done from user space via reading /proc/kallsyms. This is read by
tools like perf, but the latter is also useful for permanent live
tracing with eBPF itself in combination with stack maps when other
eBPF types are part of the callchain. See offwaketime example on
dumping stack from a map.

This work tries to tackle that issue by making the addresses and
symbols known to the kernel. The lookup from *kernel_text_address()
is implemented through a latched RB tree that can be read under
RCU in fast-path that is also shared for symbol/size/offset lookup
for a specific given address in kallsyms. The slow-path iteration
through all symbols in the seq file done via RCU list, which holds
a tiny fraction of all exported ksyms, usually below 0.1 percent.
Function symbols are exported as bpf_prog_<tag>, in order to aide
debugging and attribution. This facility is currently enabled for
root-only when bpf_jit_kallsyms is set to 1, and disabled if hardening
is active in any mode. The rationale behind this is that still a lot
of systems ship with world read permissions on kallsyms thus addresses
should not get suddenly exposed for them. If that situation gets
much better in future, we always have the option to change the
default on this. Likewise, unprivileged programs are not allowed
to add entries there either, but that is less of a concern as most
such programs types relevant in this context are for root-only anyway.
If enabled, call graphs and stack traces will then show a correct
attribution; one example is illustrated below, where the trace is
now visible in tooling such as perf script --kallsyms=/proc/kallsyms
and friends.

Before:

  7fff8166889d bpf_clone_redirect+0x80007f0020ed (/lib/modules/4.9.0-rc8+/build/vmlinux)
         f5d80 __sendmsg_nocancel+0xffff006451f1a007 (/usr/lib64/libc-2.18.so)

After:

  7fff816688b7 bpf_clone_redirect+0x80007f002107 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fffa0575728 bpf_prog_33c45a467c9e061a+0x8000600020fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fffa07ef1fc cls_bpf_classify+0x8000600020dc (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff81678b68 tc_classify+0x80007f002078 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8164d40b __netif_receive_skb_core+0x80007f0025fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8164d718 __netif_receive_skb+0x80007f002018 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8164e565 process_backlog+0x80007f002095 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8164dc71 net_rx_action+0x80007f002231 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff81767461 __softirqentry_text_start+0x80007f0020d1 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff817658ac do_softirq_own_stack+0x80007f00201c (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff810a2c20 do_softirq+0x80007f002050 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff810a2cb5 __local_bh_enable_ip+0x80007f002085 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8168d452 ip_finish_output2+0x80007f002152 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8168ea3d ip_finish_output+0x80007f00217d (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff8168f2af ip_output+0x80007f00203f (/lib/modules/4.9.0-rc8+/build/vmlinux)
  [...]
  7fff81005854 do_syscall_64+0x80007f002054 (/lib/modules/4.9.0-rc8+/build/vmlinux)
  7fff817649eb return_from_SYSCALL_64+0x80007f002000 (/lib/modules/4.9.0-rc8+/build/vmlinux)
         f5d80 __sendmsg_nocancel+0xffff01c484812007 (/usr/lib64/libc-2.18.so)

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-17 13:40:05 -05:00
David S. Miller
4e8f2fc1a5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two trivial overlapping changes conflicts in MPLS and mlx5.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-28 10:33:06 -05:00
Daniel Borkmann
d407bd25a2 bpf: don't trigger OOM killer under pressure with map alloc
This patch adds two helpers, bpf_map_area_alloc() and bpf_map_area_free(),
that are to be used for map allocations. Using kmalloc() for very large
allocations can cause excessive work within the page allocator, so i) fall
back earlier to vmalloc() when the attempt is considered costly anyway,
and even more importantly ii) don't trigger OOM killer with any of the
allocators.

Since this is based on a user space request, for example, when creating
maps with element pre-allocation, we really want such requests to fail
instead of killing other user space processes.

Also, don't spam the kernel log with warnings should any of the allocations
fail under pressure. Given that, we can make backend selection in
bpf_map_area_alloc() generic, and convert all maps over to use this API
for spots with potentially large allocation requests.

Note, replacing the one kmalloc_array() is fine as overflow checks happen
earlier in htab_map_alloc(), since it must also protect the multiplication
for vmalloc() should kmalloc_array() fail.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18 17:12:26 -05:00
David S. Miller
580bdf5650 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-01-17 15:19:37 -05:00
Daniel Borkmann
f1f7714ea5 bpf: rework prog_digest into prog_tag
Commit 7bd509e311 ("bpf: add prog_digest and expose it via
fdinfo/netlink") was recently discussed, partially due to
admittedly suboptimal name of "prog_digest" in combination
with sha1 hash usage, thus inevitably and rightfully concerns
about its security in terms of collision resistance were
raised with regards to use-cases.

The intended use cases are for debugging resp. introspection
only for providing a stable "tag" over the instruction sequence
that both kernel and user space can calculate independently.
It's not usable at all for making a security relevant decision.
So collisions where two different instruction sequences generate
the same tag can happen, but ideally at a rather low rate. The
"tag" will be dumped in hex and is short enough to introspect
in tracepoints or kallsyms output along with other data such
as stack trace, etc. Thus, this patch performs a rename into
prog_tag and truncates the tag to a short output (64 bits) to
make it obvious it's not collision-free.

Should in future a hash or facility be needed with a security
relevant focus, then we can think about requirements, constraints,
etc that would fit to that situation. For now, rework the exposed
parts for the current use cases as long as nothing has been
released yet. Tested on x86_64 and s390x.

Fixes: 7bd509e311 ("bpf: add prog_digest and expose it via fdinfo/netlink")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-16 14:03:31 -05:00
Daniel Borkmann
6b8cc1d11e bpf: pass original insn directly to convert_ctx_access
Currently, when calling convert_ctx_access() callback for the various
program types, we pass in insn->dst_reg, insn->src_reg, insn->off from
the original instruction. This information is needed to rewrite the
instruction that is based on the user ctx structure into a kernel
representation for the ctx. As we'd like to allow access size beyond
just BPF_W, we'd need also insn->code for that in order to decode the
original access size. Given that, lets just pass insn directly to the
convert_ctx_access() callback and work on that to not clutter the
callback with even more arguments we need to pass when everything is
already contained in insn. So lets go through that once, no functional
change.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-12 10:00:31 -05:00
Alexei Starovoitov
39f19ebbf5 bpf: rename ARG_PTR_TO_STACK
since ARG_PTR_TO_STACK is no longer just pointer to stack
rename it to ARG_PTR_TO_MEM and adjust comment.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-09 16:56:27 -05:00