63 Commits

Author SHA1 Message Date
Bruno Martins
9162135978 Merge branch 'deprecated/android-4.9-q' of https://android.googlesource.com/kernel/common into HEAD
Conflicts:
	arch/arm/Makefile
	arch/arm/include/asm/unistd.h
	arch/arm/kernel/calls.S
	arch/arm64/include/asm/assembler.h
	arch/arm64/include/asm/cputype.h
	arch/arm64/kernel/bpi.S
	arch/arm64/kernel/cpu_errata.c
	arch/arm64/kernel/setup.c
	arch/arm64/kernel/vdso.c
	arch/arm64/mm/proc.S
	arch/mips/include/uapi/asm/Kbuild
	arch/powerpc/include/uapi/asm/Kbuild
	drivers/char/Kconfig
	drivers/char/random.c
	drivers/clk/qcom/clk-rcg2.c
	drivers/gpu/drm/drm_edid.c
	drivers/irqchip/irq-gic.c
	drivers/md/dm-table.c
	drivers/media/dvb-core/dmxdev.c
	drivers/mmc/core/core.c
	drivers/mmc/core/host.c
	drivers/mmc/core/mmc.c
	drivers/mmc/host/sdhci.c
	drivers/net/usb/lan78xx.c
	drivers/scsi/ufs/ufs_quirks.h
	drivers/scsi/ufs/ufshcd.c
	drivers/staging/android/ion/ion-ioctl.c
	drivers/staging/android/ion/ion.c
	drivers/staging/android/ion/ion_priv.h
	drivers/staging/android/ion/ion_system_heap.c
	drivers/tty/tty_io.c
	drivers/usb/core/hub.c
	drivers/usb/core/usb.h
	drivers/usb/dwc3/core.c
	drivers/usb/dwc3/gadget.c
	drivers/usb/gadget/composite.c
	drivers/usb/gadget/configfs.c
	drivers/usb/gadget/function/f_accessory.c
	drivers/usb/gadget/function/rndis.c
	drivers/usb/gadget/function/rndis.h
	fs/eventpoll.c
	fs/ext4/namei.c
	fs/fat/fatent.c
	fs/gfs2/acl.c
	include/linux/random.h
	include/uapi/drm/Kbuild
	include/uapi/linux/Kbuild
	include/uapi/linux/cifs/Kbuild
	include/uapi/linux/genwqe/Kbuild
	kernel/cpu.c
	kernel/exit.c
	kernel/sched/cpufreq_schedutil.c
	lib/Makefile
	lib/string.c
	mm/memory.c
	mm/page-writeback.c
	mm/page_alloc.c
	net/ipv4/udp.c
	net/ipv6/datagram.c
	net/ipv6/ip6_output.c
	net/netfilter/nf_conntrack_irc.c
	net/netfilter/xt_quota2.c
	net/netlink/genetlink.c
	security/selinux/avc.c
	security/selinux/include/objsec.h
	sound/core/compress_offload.c

Change-Id: I41982a5a8e22a21b72ec5dfa61a3680be66213f4
2023-03-26 12:09:00 +01:00
Nick Desaulniers
04b8998dff lib/string.c: implement stpcpy
commit 1e1b6d63d6340764e00356873e5794225a2a03ea upstream.

LLVM implemented a recent "libcall optimization" that lowers calls to
`sprintf(dest, "%s", str)` where the return value is used to
`stpcpy(dest, str) - dest`.

This generally avoids the machinery involved in parsing format strings.
`stpcpy` is just like `strcpy` except it returns the pointer to the new
tail of `dest`.  This optimization was introduced into clang-12.

Implement this so that we don't observe linkage failures due to missing
symbol definitions for `stpcpy`.

Similar to last year's fire drill with: commit 5f074f3e192f
("lib/string.c: implement a basic bcmp")

The kernel is somewhere between a "freestanding" environment (no full
libc) and "hosted" environment (many symbols from libc exist with the
same type, function signature, and semantics).

As Peter Anvin notes, there's not really a great way to inform the
compiler that you're targeting a freestanding environment but would like
to opt-in to some libcall optimizations (see pr/47280 below), rather
than opt-out.

Arvind notes, -fno-builtin-* behaves slightly differently between GCC
and Clang, and Clang is missing many __builtin_* definitions, which I
consider a bug in Clang and am working on fixing.

Masahiro summarizes the subtle distinction between compilers justly:
  To prevent transformation from foo() into bar(), there are two ways in
  Clang to do that; -fno-builtin-foo, and -fno-builtin-bar.  There is
  only one in GCC; -fno-buitin-foo.

(Any difference in that behavior in Clang is likely a bug from a missing
__builtin_* definition.)

Masahiro also notes:
  We want to disable optimization from foo() to bar(),
  but we may still benefit from the optimization from
  foo() into something else. If GCC implements the same transform, we
  would run into a problem because it is not -fno-builtin-bar, but
  -fno-builtin-foo that disables that optimization.

  In this regard, -fno-builtin-foo would be more future-proof than
  -fno-built-bar, but -fno-builtin-foo is still potentially overkill. We
  may want to prevent calls from foo() being optimized into calls to
  bar(), but we still may want other optimization on calls to foo().

It seems that compilers today don't quite provide the fine grain control
over which libcall optimizations pseudo-freestanding environments would
prefer.

Finally, Kees notes that this interface is unsafe, so we should not
encourage its use.  As such, I've removed the declaration from any
header, but it still needs to be exported to avoid linkage errors in
modules.

Reported-by: Sami Tolvanen <samitolvanen@google.com>
Suggested-by: Andy Lavr <andy.lavr@gmail.com>
Suggested-by: Arvind Sankar <nivedita@alum.mit.edu>
Suggested-by: Joe Perches <joe@perches.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200914161643.938408-1-ndesaulniers@google.com
Link: https://bugs.llvm.org/show_bug.cgi?id=47162
Link: https://bugs.llvm.org/show_bug.cgi?id=47280
Link: https://github.com/ClangBuiltLinux/linux/issues/1126
Link: https://man7.org/linux/man-pages/man3/stpcpy.3.html
Link: https://pubs.opengroup.org/onlinepubs/9699919799/functions/stpcpy.html
Link: https://reviews.llvm.org/D85963
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: If030211a5b0bfa3c0e795a762471dca7d9873ba7
2022-09-11 21:04:59 +02:00
Bruno Martins
dbcc8fefd9 treewide: Import Samsung changes from T725XXU2DUD1
Change-Id: I5c31dc4a8006a967910963fb9e7d1a0ab4ab9731
2022-02-23 22:14:25 +01:00
Matthew Wilcox
fe0bc3fd86 lib/string.c: add multibyte memset functions
commit 3b3c4babd898715926d24ae10aa64778ace33aae upstream.

Patch series "Multibyte memset variations", v4.

A relatively common idiom we're missing is a function to fill an area of
memory with a pattern which is larger than a single byte.  I first
noticed this with a zram patch which wanted to fill a page with an
'unsigned long' value.  There turn out to be quite a few places in the
kernel which can benefit from using an optimised function rather than a
loop; sometimes text size, sometimes speed, and sometimes both.  The
optimised PowerPC version (not included here) improves performance by
about 30% on POWER8 on just the raw memset_l().

Most of the extra lines of code come from the three testcases I added.

This patch (of 8):

memset16(), memset32() and memset64() are like memset(), but allow the
caller to fill the destination with a value larger than a single byte.
memset_l() and memset_p() allow the caller to use unsigned long and
pointer values respectively.

Link: http://lkml.kernel.org/r/20170720184539.31609-2-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-04 11:58:02 +02:00
Tobin C. Harding
316c6cc08d lib/string: Add strscpy_pad() function
[ Upstream commit 458a3bf82df4fe1f951d0f52b1e0c1e9d5a88a3b ]

We have a function to copy strings safely and we have a function to copy
strings and zero the tail of the destination (if source string is
shorter than destination buffer) but we do not have a function to do
both at once.  This means developers must write this themselves if they
desire this functionality.  This is a chore, and also leaves us open to
off by one errors unnecessarily.

Add a function that calls strscpy() then memset()s the tail to zero if
the source string is shorter than the destination buffer.

Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-23 13:59:14 +01:00
Nick Desaulniers
586d6f17d8 lib/string.c: implement stpcpy
commit 1e1b6d63d6340764e00356873e5794225a2a03ea upstream.

LLVM implemented a recent "libcall optimization" that lowers calls to
`sprintf(dest, "%s", str)` where the return value is used to
`stpcpy(dest, str) - dest`.

This generally avoids the machinery involved in parsing format strings.
`stpcpy` is just like `strcpy` except it returns the pointer to the new
tail of `dest`.  This optimization was introduced into clang-12.

Implement this so that we don't observe linkage failures due to missing
symbol definitions for `stpcpy`.

Similar to last year's fire drill with: commit 5f074f3e192f
("lib/string.c: implement a basic bcmp")

The kernel is somewhere between a "freestanding" environment (no full
libc) and "hosted" environment (many symbols from libc exist with the
same type, function signature, and semantics).

As Peter Anvin notes, there's not really a great way to inform the
compiler that you're targeting a freestanding environment but would like
to opt-in to some libcall optimizations (see pr/47280 below), rather
than opt-out.

Arvind notes, -fno-builtin-* behaves slightly differently between GCC
and Clang, and Clang is missing many __builtin_* definitions, which I
consider a bug in Clang and am working on fixing.

Masahiro summarizes the subtle distinction between compilers justly:
  To prevent transformation from foo() into bar(), there are two ways in
  Clang to do that; -fno-builtin-foo, and -fno-builtin-bar.  There is
  only one in GCC; -fno-buitin-foo.

(Any difference in that behavior in Clang is likely a bug from a missing
__builtin_* definition.)

Masahiro also notes:
  We want to disable optimization from foo() to bar(),
  but we may still benefit from the optimization from
  foo() into something else. If GCC implements the same transform, we
  would run into a problem because it is not -fno-builtin-bar, but
  -fno-builtin-foo that disables that optimization.

  In this regard, -fno-builtin-foo would be more future-proof than
  -fno-built-bar, but -fno-builtin-foo is still potentially overkill. We
  may want to prevent calls from foo() being optimized into calls to
  bar(), but we still may want other optimization on calls to foo().

It seems that compilers today don't quite provide the fine grain control
over which libcall optimizations pseudo-freestanding environments would
prefer.

Finally, Kees notes that this interface is unsafe, so we should not
encourage its use.  As such, I've removed the declaration from any
header, but it still needs to be exported to avoid linkage errors in
modules.

Reported-by: Sami Tolvanen <samitolvanen@google.com>
Suggested-by: Andy Lavr <andy.lavr@gmail.com>
Suggested-by: Arvind Sankar <nivedita@alum.mit.edu>
Suggested-by: Joe Perches <joe@perches.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200914161643.938408-1-ndesaulniers@google.com
Link: https://bugs.llvm.org/show_bug.cgi?id=47162
Link: https://bugs.llvm.org/show_bug.cgi?id=47280
Link: https://github.com/ClangBuiltLinux/linux/issues/1126
Link: https://man7.org/linux/man-pages/man3/stpcpy.3.html
Link: https://pubs.opengroup.org/onlinepubs/9699919799/functions/stpcpy.html
Link: https://reviews.llvm.org/D85963
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-01 20:40:19 +02:00
jianzhou
79bbe9c88c Merge android-4.9.187 (fabc071) into msm-4.9
* refs/heads/tmp-fabc071:
  Linux 4.9.187
  ceph: hold i_ceph_lock when removing caps for freeing inode
  drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
  sched/fair: Don't free p->numa_faults with concurrent readers
  Bluetooth: hci_uart: check for missing tty operations
  media: radio-raremono: change devm_k*alloc to k*alloc
  media: cpia2_usb: first wake up, then free in disconnect
  media: au0828: fix null dereference in error path
  ISDN: hfcsusb: checking idx of ep configuration
  arm64: compat: Provide definition for COMPAT_SIGMINSTKSZ
  i2c: qup: fixed releasing dma without flush operation completion
  arm64: dts: marvell: Fix A37xx UART0 register size
  tcp: reset sk_send_head in tcp_write_queue_purge
  ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
  access: avoid the RCU grace period for the temporary subjective credentials
  powerpc/tm: Fix oops on sigreturn on systems without TM
  ALSA: hda - Add a conexant codec entry to let mute led work
  ALSA: line6: Fix wrong altsetting for LINE6_PODHD500_1
  hpet: Fix division by zero in hpet_time_div()
  x86/speculation/mds: Apply more accurate check on hypervisor platform
  x86/sysfb_efi: Add quirks for some devices with swapped width and height
  usb: pci-quirks: Correct AMD PLL quirk detection
  usb: wusbcore: fix unbalanced get/put cluster_id
  locking/lockdep: Hide unused 'class' variable
  locking/lockdep: Fix lock used or unused stats error
  mm/mmu_notifier: use hlist_add_head_rcu()
  9p: pass the correct prototype to read_cache_page
  mm/kmemleak.c: fix check for softirq context
  sh: prevent warnings when using iounmap
  powerpc/eeh: Handle hugepages in ioremap space
  mailbox: handle failed named mailbox channel request
  f2fs: avoid out-of-range memory access
  powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
  RDMA/rxe: Fill in wc byte_len with IB_WC_RECV_RDMA_WITH_IMM
  perf test mmap-thread-lookup: Initialize variable to suppress memory sanitizer warning
  kallsyms: exclude kasan local symbols on s390
  serial: sh-sci: Fix TX DMA buffer flushing and workqueue races
  serial: sh-sci: Terminate TX DMA during buffer flushing
  RDMA/i40iw: Set queue pair state when being queried
  powerpc/4xx/uic: clear pending interrupt after irq type/pol change
  um: Silence lockdep complaint about mmap_sem
  mfd: hi655x-pmic: Fix missing return value check for devm_regmap_init_mmio_clk
  mfd: arizona: Fix undefined behavior
  mfd: core: Set fwnode for created devices
  recordmcount: Fix spurious mcount entries on powerpc
  iio: iio-utils: Fix possible incorrect mask calculation
  PCI: xilinx-nwl: Fix Multi MSI data programming
  kbuild: Add -Werror=unknown-warning-option to CLANG_FLAGS
  PCI: sysfs: Ignore lockdep for remove attribute
  powerpc/pci/of: Fix OF flags parsing for 64bit BARs
  usb: gadget: Zero ffs_io_data
  tty: serial_core: Set port active bit in uart_port_activate
  drm/rockchip: Properly adjust to a true clock in adjusted_mode
  phy: renesas: rcar-gen2: Fix memory leak at error paths
  drm/virtio: Add memory barriers for capset cache.
  serial: 8250: Fix TX interrupt handling condition
  tty: serial: msm_serial: avoid system lockup condition
  tty/serial: digicolor: Fix digicolor-usart already registered warning
  memstick: Fix error cleanup path of memstick_init
  drm/bridge: sii902x: pixel clock unit is 10kHz instead of 1kHz
  drm/bridge: tc358767: read display_props in get_modes()
  tty: serial: cpm_uart - fix init when SMC is relocated
  pinctrl: rockchip: fix leaked of_node references
  tty: max310x: Fix invalid baudrate divisors calculator
  usb: core: hub: Disable hub-initiated U1/U2
  drm/panel: simple: Fix panel_simple_dsi_probe
  nfsd: Fix overflow causing non-working mounts on 1 TB machines
  nfsd: fix performance-limiting session calculation
  nfsd: give out fewer session slots as limit approaches
  nfsd: increase DRC cache limit
  NFSv4: Fix open create exclusive when the server reboots
  perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id
  perf/x86/amd/uncore: Get correct number of cores sharing last level cache
  perf/x86/amd/uncore: Rename 'L2' to 'LLC'
  net: bridge: stp: don't cache eth dest pointer before skb pull
  net: bridge: mcast: fix stale ipv6 hdr pointer when handling v6 query
  net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling
  tcp: Reset bytes_acked and bytes_received when disconnecting
  bonding: validate ip header before check IPPROTO_IGMP
  netrom: hold sock when setting skb->destructor
  netrom: fix a memory leak in nr_rx_frame()
  macsec: fix checksumming after decryption
  macsec: fix use-after-free of skb during RX
  vrf: make sure skb->data contains ip header to make routing
  sky2: Disable MSI on ASUS P6T
  rxrpc: Fix send on a connected, but unbound socket
  nfc: fix potential illegal memory access
  net: openvswitch: fix csum updates for MPLS actions
  net: neigh: fix multiple neigh timer scheduling
  net: dsa: mv88e6xxx: wait after reset deactivation
  net: bcmgenet: use promisc for unsupported filters
  ipv4: don't set IPv6 only flags to IPv4 addresses
  igmp: fix memory leak in igmpv3_del_delrec()
  caif-hsi: fix possible deadlock in cfhsi_exit_module()
  bnx2x: Prevent ptp_task to be rescheduled indefinitely
  bnx2x: Prevent load reordering in tx completion processing
  ext4: allow directory holes
  lib/strscpy: Shut up KASAN false-positives in strscpy()
  compiler.h: Add read_word_at_a_time() function.
  compiler.h, kasan: Avoid duplicating __read_once_size_nocheck()
  dm bufio: fix deadlock with loop device
  usb: Handle USB3 remote wakeup for LPM enabled devices correctly
  Bluetooth: Add SMP workaround Microsoft Surface Precision Mouse bug
  intel_th: msu: Fix single mode with disabled IOMMU
  eCryptfs: fix a couple type promotion bugs
  powerpc/watchpoint: Restore NV GPRs while returning from exception
  powerpc/32s: fix suspend/resume when IBATs 4-7 are used
  parisc: Fix kernel panic due invalid values in IAOQ0 or IAOQ1
  parisc: Ensure userspace privilege for ptraced processes in regset functions
  um: Fix FP register size for XSTATE/XSAVE
  um: Allow building and running on older hosts
  crypto: caam - limit output IV to CBC to work around CTR mode DMA issue
  PCI: hv: Fix a use-after-free bug in hv_eject_device_work()
  PCI: hv: Delete the device earlier from hbus->children for hot-remove
  crypto: ccp - Validate the the error value used to index error messages
  gpu: ipu-v3: ipu-ic: Fix saturation bit offset in TPMEM
  coda: pass the host file in vma->vm_file on mmap
  floppy: fix out-of-bounds read in copy_buffer
  floppy: fix invalid pointer dereference in drive_name
  floppy: fix out-of-bounds read in next_valid_format
  floppy: fix div-by-zero in setup_format_params
  take floppy compat ioctls to sodding floppy.c
  libnvdimm/pfn: fix fsdax-mode namespace info-block zero-fields
  Btrfs: add missing inode version, ctime and mtime updates when punching hole
  PCI: Do not poll for PME if the device is in D3cold
  9p/virtio: Add cleanup path in p9_virtio_init
  padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
  drm/nouveau/i2c: Enable i2c pads & busses during preinit
  fs/proc/proc_sysctl.c: fix the default values of i_uid/i_gid on /proc/sys inodes.
  arm64: tegra: Fix AGIC register range
  KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed
  media: coda: Remove unbalanced and unneeded mutex unlock
  media: v4l2: Test type instead of cfg->type in v4l2_ctrl_new_custom()
  ALSA: hda/realtek: apply ALC891 headset fixup to one Dell machine
  ALSA: seq: Break too long mutex context in the write loop
  lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
  NFSv4: Handle the special Linux file open access mode
  tracing/snapshot: Resize spare buffer if size changed
  iwlwifi: pcie: don't service an interrupt that was masked
  arm64: tegra: Update Jetson TX1 GPU regulator timings
  regulator: s2mps11: Fix buck7 and buck8 wrong voltages
  Input: gtco - bounds check collection indent level
  crypto: crypto4xx - fix a potential double free in ppc4xx_trng_probe
  crypto: chacha20poly1305 - fix atomic sleep when using async algorithm
  crypto: arm64/sha2-ce - correct digest for empty data in finup
  crypto: arm64/sha1-ce - correct digest for empty data in finup
  crypto: ghash - fix unaligned memory access in ghash_setkey()
  scsi: mac_scsi: Increase PIO/PDMA transfer length threshold
  scsi: NCR5380: Always re-enable reselection interrupt
  scsi: NCR5380: Reduce goto statements in NCR5380_select()
  xen: let alloc_xenballooned_pages() fail if not enough memory free
  gtp: fix use-after-free in gtp_newlink()
  gtp: fix Illegal context switch in RCU read-side critical section.
  Bluetooth: validate BLE connection interval updates
  Bluetooth: Check state in l2cap_disconnect_rsp
  Bluetooth: 6lowpan: search for destination address in all peers
  Bluetooth: hci_bcsp: Fix memory leak in rx_skb
  gpiolib: Fix references to gpiod_[gs]et_*value_cansleep() variants
  net: usb: asix: init MAC address buffers
  iwlwifi: mvm: Drop large non sta frames
  bcache: check c->gc_thread by IS_ERR_OR_NULL in cache_set_flush()
  EDAC: Fix global-out-of-bounds write when setting edac_mc_poll_msec
  crypto: asymmetric_keys - select CRYPTO_HASH where needed
  ixgbe: Check DDM existence in transceiver before access
  rslib: Fix handling of of caller provided syndrome
  rslib: Fix decoding of shortened codes
  clocksource/drivers/exynos_mct: Increase priority over ARM arch timer
  libata: don't request sense data on !ZAC ATA devices
  perf tools: Increase MAX_NR_CPUS and MAX_CACHES
  ath10k: fix PCIE device wake up failed
  mt7601u: fix possible memory leak when the device is disconnected
  x86/build: Add 'set -e' to mkcapflags.sh to delete broken capflags.c
  mt7601u: do not schedule rx_tasklet when the device has been disconnected
  media: coda: increment sequence offset for the last returned frame
  media: coda: fix mpeg2 sequence number handling
  acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
  timer_list: Guard procfs specific code
  ntp: Limit TAI-UTC offset
  media: i2c: fix warning same module names
  ipsec: select crypto ciphers for xfrm_algo
  EDAC/sysfs: Fix memory leak when creating a csrow object
  ipoib: correcly show a VF hardware address
  vhost_net: disable zerocopy by default
  perf evsel: Make perf_evsel__name() accept a NULL argument
  xfrm: fix sa selector validation
  blkcg, writeback: dead memcgs shouldn't contribute to writeback ownership arbitration
  rcu: Force inlining of rcu_read_lock()
  bpf: silence warning messages in core
  regmap: fix bulk writes on paged registers
  gpio: omap: ensure irq is enabled before wakeup
  gpio: omap: fix lack of irqstatus_raw0 for OMAP4
  perf test 6: Fix missing kvm module load for s390
  perf cs-etm: Properly set the value of 'old' and 'head' in snapshot mode
  s390/qdio: handle PENDING state for QEBSM devices
  net: axienet: Fix race condition causing TX hang
  net: fec: Do not use netdev messages too early
  cpupower : frequency-set -r option misses the last cpu in related cpu list
  media: wl128x: Fix some error handling in fm_v4l2_init_video_device()
  locking/lockdep: Fix merging of hlocks with non-zero references
  tua6100: Avoid build warnings.
  crypto: talitos - Align SEC1 accesses to 32 bits boundaries.
  crypto: talitos - properly handle split ICV.
  net: phy: Check against net_device being NULL
  media: staging: media: davinci_vpfe: - Fix for memory leak if decoder initialization fails.
  media: mc-device.c: don't memset __user pointer contents
  xfrm: Fix xfrm sel prefix length validation
  af_key: fix leaks in key_pol_get_resp and dump_sp.
  signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig
  net: stmmac: dwmac4/5: Clear unused address entries
  net: stmmac: dwmac1000: Clear unused address entries
  media: media_device_enum_links32: clean a reserved field
  media: vpss: fix a potential NULL pointer dereference
  media: marvell-ccic: fix DMA s/g desc number calculation
  crypto: talitos - fix skcipher failure due to wrong output IV
  media: dvb: usb: fix use after free in dvb_usb_device_exit
  batman-adv: fix for leaked TVLV handler.
  ath: DFS JP domain W56 fixed pulse type 3 RADAR detection
  ath6kl: add some bounds checking
  ath9k: Check for errors when reading SREV register
  ath10k: Do not send probe response template for mesh
  dmaengine: imx-sdma: fix use-after-free on probe error path
  arm64/efi: Mark __efistub_stext_offset as an absolute symbol explicitly
  MIPS: fix build on non-linux hosts
  MIPS: ath79: fix ar933x uart parity mode
  ext4: remove unused value
  f2fs: use EINVAL for superblock with invalid magic
  f2fs: fix to read source block before invalidating it
  f2fs: remove redundant check from f2fs_setflags_common()
  f2fs: use generic checking and prep function for FS_IOC_SETFLAGS
  vfs: use READ_ONCE() to access ->i_link
  fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
  ANDROID: enable CONFIG_RTC_DRV_TEST on cuttlefish
  ANDROID: xfrm: remove in_compat_syscall() checks
  UPSTREAM: binder: Set end of SG buffer area properly.
  fscrypt: cache decrypted symlink target in ->i_link
  fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext
  ext4: remove unused d_name argument from ext4_search_dir() et al.
  fscrypt: only set dentry_operations on ciphertext dentries
  fscrypt: fix race allowing rename() and link() of ciphertext dentries
  fscrypt: clean up and improve dentry revalidation
  fscrypt: use READ_ONCE() to access ->i_crypt_info
  fscrypt: remove WARN_ON_ONCE() when decryption fails
  fscrypt: drop inode argument from fscrypt_get_ctx()
  f2fs: improve print log in f2fs_sanity_check_ckpt()
  f2fs: avoid out-of-range memory access
  f2fs: fix to avoid long latency during umount
  f2fs: allow all the users to pin a file
  f2fs: support swap file w/ DIO
  f2fs: allocate blocks for pinned file
  f2fs: fix is_idle() check for discard type
  f2fs: add a rw_sem to cover quota flag changes
  f2fs: set SBI_NEED_FSCK for xattr corruption case
  f2fs: use generic EFSBADCRC/EFSCORRUPTED
  f2fs: Use DIV_ROUND_UP() instead of open-coding
  f2fs: print kernel message if filesystem is inconsistent
  f2fs: introduce f2fs_<level> macros to wrap f2fs_printk()
  f2fs: avoid get_valid_blocks() for cleanup
  f2fs: ioctl for removing a range from F2FS
  f2fs: only set project inherit bit for directory
  f2fs: separate f2fs i_flags from fs_flags and ext4 i_flags
  f2fs: Add option to limit required GC for checkpoint=disable
  f2fs: Fix accounting for unusable blocks
  f2fs: Fix root reserved on remount
  f2fs: Lower threshold for disable_cp_again
  f2fs: fix sparse warning
  f2fs: fix f2fs_show_options to show nodiscard mount option
  f2fs: add error prints for debugging mount failure
  f2fs: fix to do sanity check on segment bitmap of LFS curseg
  f2fs: add missing sysfs entries in documentation
  f2fs: fix to avoid deadloop if data_flush is on
  f2fs: always assume that the device is idle under gc_urgent
  f2fs: add bio cache for IPU
  f2fs: allow ssr block allocation during checkpoint=disable period
  f2fs: fix to check layout on last valid checkpoint park

Conflicts:
	drivers/tty/serial/msm_serial.c
	fs/crypto/bio.c
	fs/crypto/keyinfo.c
	fs/f2fs/data.c

Change-Id: I400b66ca62d751839b3e0499cb6c797f5f70b554
Signed-off-by: jianzhou <jianzhou@codeaurora.org>
2019-10-11 14:38:02 +08:00
Andrey Ryabinin
8dd8b4d7a0 lib/strscpy: Shut up KASAN false-positives in strscpy()
[ Upstream commit 1a3241ff10d038ecd096d03380327f2a0b5840a6 ]

strscpy() performs the word-at-a-time optimistic reads.  So it may may
access the memory past the end of the object, which is perfectly fine
since strscpy() doesn't use that (past-the-end) data and makes sure the
optimistic read won't cross a page boundary.

Use new read_word_at_a_time() to shut up the KASAN.

Note that this potentially could hide some bugs.  In example bellow,
stscpy() will copy more than we should (1-3 extra uninitialized bytes):

        char dst[8];
        char *src;

        src = kmalloc(5, GFP_KERNEL);
        memset(src, 0xff, 5);
        strscpy(dst, src, 8);

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04 09:33:32 +02:00
jianzhou
45728c3f55 Merge android-4.9.169 (1ef64da) into msm-4.9
* refs/heads/tmp-1ef64da :
  Linux 4.9.169
  PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller
  xtensa: fix return_address
  sched/fair: Do not re-read ->h_load_next during hierarchical load calculation
  xen: Prevent buffer overflow in privcmd ioctl
  parisc: Use cr16 interval timers unconditionally on qemu
  arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value
  ARM: dts: at91: Fix typo in ISC_D0 on PC9
  virtio: Honour 'may_reduce_num' in vring_create_virtqueue
  genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent()
  block: do not leak memory in bio_copy_user_iov()
  Btrfs: do not allow trimming when a fs is mounted with the nologreplay option
  ASoC: fsl_esai: fix channel swap issue when stream starts
  include/linux/bitrev.h: fix constant bitrev
  parisc: Detect QEMU earlier in boot process
  ALSA: seq: Fix OOB-reads from strlcpy
  ip6_tunnel: Match to ARPHRD_TUNNEL6 for dev type
  net: ethtool: not call vzalloc for zero sized memory request
  netns: provide pure entropy for net_hash_mix()
  net/mlx5e: Add a lock on tir list
  bnxt_en: Improve RX consumer index validity check.
  bnxt_en: Reset device on RX buffer errors.
  vrf: check accept_source_route on the original netdevice
  tcp: Ensure DCTCP reacts to losses
  sctp: initialize _pad of sockaddr_in before copying to user memory
  qmi_wwan: add Olicard 600
  openvswitch: fix flow actions reallocation
  net: rds: force to destroy connection if t_sock is NULL in rds_tcp_kill_sock().
  kcm: switch order of device registration to fix a crash
  ipv6: sit: reset ip header pointer in ipip6_rcv
  ipv6: Fix dangling pointer when ipv6 fragment
  tty: ldisc: add sysctl to prevent autoloading of ldiscs
  tty: mark Siemens R3964 line discipline as BROKEN
  arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region
  powerpc/security: Fix spectre_v2 reporting
  powerpc/fsl: Fix the flush of branch predictor.
  powerpc/fsl: Fixed warning: orphan section `__btb_flush_fixup'
  powerpc/fsl: Update Spectre v2 reporting
  powerpc/fsl: Enable runtime patching if nospectre_v2 boot arg is used
  powerpc/fsl: Flush branch predictor when entering KVM
  powerpc/fsl: Flush the branch predictor at each kernel entry (32 bit)
  powerpc/fsl: Flush the branch predictor at each kernel entry (64bit)
  powerpc/fsl: Add nospectre_v2 command line argument
  powerpc/fsl: Emulate SPRN_BUCSR register
  powerpc/fsl: Fix spectre_v2 mitigations reporting
  powerpc/fsl: Add macro to flush the branch predictor
  powerpc/fsl: Add infrastructure to fixup branch predictor flush
  powerpc/powernv: Query firmware for count cache flush settings
  powerpc/pseries: Query hypervisor for count cache flush settings
  powerpc/64s: Add support for software count cache flush
  powerpc/64s: Add new security feature flags for count cache flush
  powerpc/asm: Add a patch_site macro & helpers for patching instructions
  powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit platforms
  powerpc/fsl: Add barrier_nospec implementation for NXP PowerPC Book3E
  powerpc/64: Make meltdown reporting Book3S 64 specific
  powerpc/64: Call setup_barrier_nospec() from setup_arch()
  powerpc/64: Add CONFIG_PPC_BARRIER_NOSPEC
  powerpc/64: Make stf barrier PPC_BOOK3S_64 specific.
  powerpc/64: Disable the speculation barrier from the command line
  powerpc64s: Show ori31 availability in spectre_v1 sysfs file not v2
  powerpc/64s: Enhance the information in cpu_show_spectre_v1()
  powerpc/64: Use barrier_nospec in syscall entry
  powerpc: Use barrier_nospec in copy_from_user()
  powerpc/64s: Enable barrier_nospec based on firmware settings
  powerpc/64s: Patch barrier_nospec in modules
  powerpc: Avoid code patching freed init sections
  powerpc/64s: Add support for ori barrier_nospec patching
  powerpc/64s: Add barrier_nospec
  powerpc: Fix invalid use of register expressions
  lib/string.c: implement a basic bcmp
  x86/vdso: Drop implicit common-page-size linker flag
  x86: vdso: Use $LD instead of $CC to link
  kbuild: clang: choose GCC_TOOLCHAIN_DIR not on LD
  powerpc/tm: Limit TM code inside PPC_TRANSACTIONAL_MEM
  x86/power: Make restore_processor_context() sane
  x86/power/32: Move SYSENTER MSR restoration to fix_processor_context()
  x86/power/64: Use struct desc_ptr for the IDT in struct saved_context
  x86/power: Fix some ordering bugs in __restore_processor_context()
  ANDROID: Makefile: Add '-fsplit-lto-unit' to cfi-clang-flags

Conflicts:
	drivers/tty/Kconfig

Change-Id: Ic2f7a4f7bd94d8345c34293bf933b2ed13680155
Signed-off-by: jianzhou <jianzhou@codeaurora.org>
2019-05-30 14:10:21 +08:00
Nick Desaulniers
7eceaf5bbf lib/string.c: implement a basic bcmp
[ Upstream commit 5f074f3e192f10c9fade898b9b3b8812e3d83342 ]

A recent optimization in Clang (r355672) lowers comparisons of the
return value of memcmp against zero to comparisons of the return value
of bcmp against zero.  This helps some platforms that implement bcmp
more efficiently than memcmp.  glibc simply aliases bcmp to memcmp, but
an optimized implementation is in the works.

This results in linkage failures for all targets with Clang due to the
undefined symbol.  For now, just implement bcmp as a tailcail to memcmp
to unbreak the build.  This routine can be further optimized in the
future.

Other ideas discussed:

 * A weak alias was discussed, but breaks for architectures that define
   their own implementations of memcmp since aliases to declarations are
   not permitted (only definitions). Arch-specific memcmp
   implementations typically declare memcmp in C headers, but implement
   them in assembly.

 * -ffreestanding also is used sporadically throughout the kernel.

 * -fno-builtin-bcmp doesn't work when doing LTO.

Link: https://bugs.llvm.org/show_bug.cgi?id=41035
Link: https://code.woboq.org/userspace/glibc/string/memcmp.c.html#bcmp
Link: 8e16d73346
Link: https://github.com/ClangBuiltLinux/linux/issues/416
Link: http://lkml.kernel.org/r/20190313211335.165605-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Reported-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: James Y Knight <jyknight@google.com>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17 08:36:39 +02:00
Daniel Micay
0f51310ad5 include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time.  Unlike glibc,
it covers buffer reads in addition to writes.

GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation.  They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks.  Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.

This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code.  There will likely be issues caught in
regular use at runtime too.

Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:

* Some of the fortified string functions (strncpy, strcat), don't yet
  place a limit on reads from the source based on __builtin_object_size of
  the source buffer.

* Extending coverage to more string functions like strlcat.

* It should be possible to optionally use __builtin_object_size(x, 1) for
  some functions (C strings) to detect intra-object overflows (like
  glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
  approach to avoid likely compatibility issues.

* The compile-time checks should be made available via a separate config
  option which can be enabled by default (or always enabled) once enough
  time has passed to get the issues it catches fixed.

Kees said:
 "This is great to have. While it was out-of-tree code, it would have
  blocked at least CVE-2016-3858 from being exploitable (improper size
  argument to strlcpy()). I've sent a number of fixes for
  out-of-bounds-reads that this detected upstream already"

Change-Id: I4c6ba947ffc296caf1b074f7ef4a3b64877230ea
[arnd@arndb.de: x86: fix fortified memcpy]
  Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
  Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 6974f0c4555e285ab217cee58b6e874f776ff409
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2017-08-07 17:43:55 -07:00
Kees Cook
ef95159907 lib: move strtobool() to kstrtobool()
Create the kstrtobool_from_user() helper and move strtobool() logic into
the new kstrtobool() (matching all the other kstrto* functions).
Provides an inline wrapper for existing strtobool() callers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Steve French <sfrench@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Andy Shevchenko
56b060814e lib/string: introduce match_string() helper
Occasionally we have to search for an occurrence of a string in an array
of strings.  Make a simple helper for that purpose.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: David Airlie <airlied@linux.ie>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Andy Shevchenko
3368e8fbcd lib/string.c: add ULL suffix to the constant definition
8-byte constant is too big for long and compiler complains about this.

  lib/string.c:907:20: warning: constant 0x0101010101010101 is so big it is long

Append ULL suffix to explicitly show its type.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-10 16:32:11 -08:00
Chris Metcalf
990486c8af strscpy: zero any trailing garbage bytes in the destination
It's possible that the destination can be shadowed in userspace
(as, for example, the perf buffers are now).  So we should take
care not to leak data that could be inspected by userspace.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
2015-10-06 14:53:18 -04:00
Chris Metcalf
30035e4575 string: provide strscpy()
The strscpy() API is intended to be used instead of strlcpy(),
and instead of most uses of strncpy().

- Unlike strlcpy(), it doesn't read from memory beyond (src + size).

- Unlike strlcpy() or strncpy(), the API provides an easy way to check
  for destination buffer overflow: an -E2BIG error return value.

- The provided implementation is robust in the face of the source
  buffer being asynchronously changed during the copy, unlike the
  current implementation of strlcpy().

- Unlike strncpy(), the destination buffer will be NUL-terminated
  if the string in the source buffer is too long.

- Also unlike strncpy(), the destination buffer will not be updated
  beyond the NUL termination, avoiding strncpy's behavior of zeroing
  the entire tail end of the destination buffer.  (A memset() after
  the strscpy() can be used if this behavior is desired.)

- The implementation should be reasonably performant on all
  platforms since it uses the asm/word-at-a-time.h API rather than
  simple byte copy.  Kernel-to-kernel string copy is not considered
  to be performance critical in any case.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
2015-09-10 15:36:59 -04:00
Rasmus Villemoes
94df290404 lib/string.c: introduce strreplace()
Strings are sometimes sanitized by replacing a certain character (often
'/') by another (often '!').  In a few places, this is done the same way
Schlemiel the Painter would do it.  Others are slightly smarter but still
do multiple strchr() calls.  Introduce strreplace() to do this using a
single function call and a single pass over the string.

One would expect the return value to be one of three things: void, s, or
the number of replacements made.  I chose the fourth, returning a pointer
to the end of the string.  This is more likely to be useful (for example
allowing the caller to avoid a strlen call).

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25 17:00:40 -07:00
Daniel Borkmann
7829fb09a2 lib: make memzero_explicit more robust against dead store elimination
In commit 0b053c9518 ("lib: memzero_explicit: use barrier instead
of OPTIMIZER_HIDE_VAR"), we made memzero_explicit() more robust in
case LTO would decide to inline memzero_explicit() and eventually
find out it could be elimiated as dead store.

While using barrier() works well for the case of gcc, recent efforts
from LLVMLinux people suggest to use llvm as an alternative to gcc,
and there, Stephan found in a simple stand-alone user space example
that llvm could nevertheless optimize and thus elimitate the memset().
A similar issue has been observed in the referenced llvm bug report,
which is regarded as not-a-bug.

Based on some experiments, icc is a bit special on its own, while it
doesn't seem to eliminate the memset(), it could do so with an own
implementation, and then result in similar findings as with llvm.

The fix in this patch now works for all three compilers (also tested
with more aggressive optimization levels). Arguably, in the current
kernel tree it's more of a theoretical issue, but imho, it's better
to be pedantic about it.

It's clearly visible with gcc/llvm though, with the below code: if we
would have used barrier() only here, llvm would have omitted clearing,
not so with barrier_data() variant:

  static inline void memzero_explicit(void *s, size_t count)
  {
    memset(s, 0, count);
    barrier_data(s);
  }

  int main(void)
  {
    char buff[20];
    memzero_explicit(buff, sizeof(buff));
    return 0;
  }

  $ gcc -O2 test.c
  $ gdb a.out
  (gdb) disassemble main
  Dump of assembler code for function main:
   0x0000000000400400  <+0>: lea   -0x28(%rsp),%rax
   0x0000000000400405  <+5>: movq  $0x0,-0x28(%rsp)
   0x000000000040040e <+14>: movq  $0x0,-0x20(%rsp)
   0x0000000000400417 <+23>: movl  $0x0,-0x18(%rsp)
   0x000000000040041f <+31>: xor   %eax,%eax
   0x0000000000400421 <+33>: retq
  End of assembler dump.

  $ clang -O2 test.c
  $ gdb a.out
  (gdb) disassemble main
  Dump of assembler code for function main:
   0x00000000004004f0  <+0>: xorps  %xmm0,%xmm0
   0x00000000004004f3  <+3>: movaps %xmm0,-0x18(%rsp)
   0x00000000004004f8  <+8>: movl   $0x0,-0x8(%rsp)
   0x0000000000400500 <+16>: lea    -0x18(%rsp),%rax
   0x0000000000400505 <+21>: xor    %eax,%eax
   0x0000000000400507 <+23>: retq
  End of assembler dump.

As gcc, clang, but also icc defines __GNUC__, it's sufficient to define
this in compiler-gcc.h only to be picked up. For a fallback or otherwise
unsupported compiler, we define it as a barrier. Similarly, for ecc which
does not support gcc inline asm.

Reference: https://llvm.org/bugs/show_bug.cgi?id=15495
Reported-by: Stephan Mueller <smueller@chronox.de>
Tested-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Stephan Mueller <smueller@chronox.de>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: mancha security <mancha1@zoho.com>
Cc: Mark Charlebois <charlebm@gmail.com>
Cc: Behan Webster <behanw@converseincode.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-05-04 17:49:51 +08:00
mancha security
0b053c9518 lib: memzero_explicit: use barrier instead of OPTIMIZER_HIDE_VAR
OPTIMIZER_HIDE_VAR(), as defined when using gcc, is insufficient to
ensure protection from dead store optimization.

For the random driver and crypto drivers, calls are emitted ...

  $ gdb vmlinux
  (gdb) disassemble memzero_explicit
  Dump of assembler code for function memzero_explicit:
    0xffffffff813a18b0 <+0>:	push   %rbp
    0xffffffff813a18b1 <+1>:	mov    %rsi,%rdx
    0xffffffff813a18b4 <+4>:	xor    %esi,%esi
    0xffffffff813a18b6 <+6>:	mov    %rsp,%rbp
    0xffffffff813a18b9 <+9>:	callq  0xffffffff813a7120 <memset>
    0xffffffff813a18be <+14>:	pop    %rbp
    0xffffffff813a18bf <+15>:	retq
  End of assembler dump.

  (gdb) disassemble extract_entropy
  [...]
    0xffffffff814a5009 <+313>:	mov    %r12,%rdi
    0xffffffff814a500c <+316>:	mov    $0xa,%esi
    0xffffffff814a5011 <+321>:	callq  0xffffffff813a18b0 <memzero_explicit>
    0xffffffff814a5016 <+326>:	mov    -0x48(%rbp),%rax
  [...]

... but in case in future we might use facilities such as LTO, then
OPTIMIZER_HIDE_VAR() is not sufficient to protect gcc from a possible
eviction of the memset(). We have to use a compiler barrier instead.

Minimal test example when we assume memzero_explicit() would *not* be
a call, but would have been *inlined* instead:

  static inline void memzero_explicit(void *s, size_t count)
  {
    memset(s, 0, count);
    <foo>
  }

  int main(void)
  {
    char buff[20];

    snprintf(buff, sizeof(buff) - 1, "test");
    printf("%s", buff);

    memzero_explicit(buff, sizeof(buff));
    return 0;
  }

With <foo> := OPTIMIZER_HIDE_VAR():

  (gdb) disassemble main
  Dump of assembler code for function main:
  [...]
   0x0000000000400464 <+36>:	callq  0x400410 <printf@plt>
   0x0000000000400469 <+41>:	xor    %eax,%eax
   0x000000000040046b <+43>:	add    $0x28,%rsp
   0x000000000040046f <+47>:	retq
  End of assembler dump.

With <foo> := barrier():

  (gdb) disassemble main
  Dump of assembler code for function main:
  [...]
   0x0000000000400464 <+36>:	callq  0x400410 <printf@plt>
   0x0000000000400469 <+41>:	movq   $0x0,(%rsp)
   0x0000000000400471 <+49>:	movq   $0x0,0x8(%rsp)
   0x000000000040047a <+58>:	movl   $0x0,0x10(%rsp)
   0x0000000000400482 <+66>:	xor    %eax,%eax
   0x0000000000400484 <+68>:	add    $0x28,%rsp
   0x0000000000400488 <+72>:	retq
  End of assembler dump.

As can be seen, movq, movq, movl are being emitted inlined
via memset().

Reference: http://thread.gmane.org/gmane.linux.kernel.cryptoapi/13764/
Fixes: d4c5efdb97 ("random: add and use memzero_explicit() for clearing data")
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: mancha security <mancha1@zoho.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-20 07:56:12 +11:00
Linus Torvalds
fee5429e02 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Here is the crypto update for 3.20:

   - Added 192/256-bit key support to aesni GCM.
   - Added MIPS OCTEON MD5 support.
   - Fixed hwrng starvation and race conditions.
   - Added note that memzero_explicit is not a subsitute for memset.
   - Added user-space interface for crypto_rng.
   - Misc fixes"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (71 commits)
  crypto: tcrypt - do not allocate iv on stack for aead speed tests
  crypto: testmgr - limit IV copy length in aead tests
  crypto: tcrypt - fix buflen reminder calculation
  crypto: testmgr - mark rfc4106(gcm(aes)) as fips_allowed
  crypto: caam - fix resource clean-up on error path for caam_jr_init
  crypto: caam - pair irq map and dispose in the same function
  crypto: ccp - terminate ccp_support array with empty element
  crypto: caam - remove unused local variable
  crypto: caam - remove dead code
  crypto: caam - don't emit ICV check failures to dmesg
  hwrng: virtio - drop extra empty line
  crypto: replace scatterwalk_sg_next with sg_next
  crypto: atmel - Free memory in error path
  crypto: doc - remove colons in comments
  crypto: seqiv - Ensure that IV size is at least 8 bytes
  crypto: cts - Weed out non-CBC algorithms
  MAINTAINERS: add linux-crypto to hw random
  crypto: cts - Remove bogus use of seqiv
  crypto: qat - don't need qat_auth_state struct
  crypto: algif_rng - fix sparse non static symbol warning
  ...
2015-02-14 09:47:01 -08:00
Rasmus Villemoes
8da53d4595 lib/string.c: improve strrchr()
Instead of potentially passing over the string twice in case c is not
found, just keep track of the last occurrence.  According to
bloat-o-meter, this also cuts the generated code by a third (54 vs 36
bytes).  Oh, and we get rid of those 7-space indented lines.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:36 -08:00
Rasmus Villemoes
af3cd13501 lib/string.c: remove strnicmp()
Now that all in-tree users of strnicmp have been converted to
strncasecmp, the wrapper can be removed.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: David Howells <dhowells@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:14 -08:00
Daniel Borkmann
8155330aad lib: memzero_explicit: add comment for its usage
Lets improve the comment to add a note on when to use memzero_explicit()
for those not digging through the git logs. We don't want people to
pollute places with memzero_explicit() where it's not really necessary.

Reference: https://lkml.org/lkml/2015/1/4/190
Suggested-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-01-08 21:46:19 +11:00
Linus Torvalds
14d4cc0883 Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random
Pull /dev/random updates from Ted Ts'o:
 "This adds a memzero_explicit() call which is guaranteed not to be
  optimized away by GCC.  This is important when we are wiping
  cryptographically sensitive material"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  crypto: memzero_explicit - make sure to clear out sensitive data
  random: add and use memzero_explicit() for clearing data
2014-10-24 12:33:32 -07:00
Daniel Borkmann
d4c5efdb97 random: add and use memzero_explicit() for clearing data
zatimend has reported that in his environment (3.16/gcc4.8.3/corei7)
memset() calls which clear out sensitive data in extract_{buf,entropy,
entropy_user}() in random driver are being optimized away by gcc.

Add a helper memzero_explicit() (similarly as explicit_bzero() variants)
that can be used in such cases where a variable with sensitive data is
being cleared out in the end. Other use cases might also be in crypto
code. [ I have put this into lib/string.c though, as it's always built-in
and doesn't need any dependencies then. ]

Fixes kernel bugzilla: 82041

Reported-by: zatimend@hotmail.co.uk
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-10-17 11:37:29 -04:00
Rasmus Villemoes
b0bfb63118 lib: string: Make all calls to strnicmp into calls to strncasecmp
The previous patch made strnicmp into a wrapper for strncasecmp.

This patch makes all in-tree users of strnicmp call strncasecmp
directly, while still making sure that the strnicmp symbol can be used
by out-of-tree modules.  It should be considered a temporary hack until
all in-tree callers have been converted.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 02:18:23 +02:00
Rasmus Villemoes
cd514e727b lib/string.c: remove duplicated function
lib/string.c contains two functions, strnicmp and strncasecmp, which do
roughly the same thing, namely compare two strings case-insensitively up
to a given bound.  They have slightly different implementations, but the
only important difference is that strncasecmp doesn't handle len==0
appropriately; it effectively becomes strcasecmp in that case.  strnicmp
correctly says that two strings are always equal in their first 0
characters.

strncasecmp is the POSIX name for this functionality.  So rename the
non-broken function to the standard name.  To minimize the impact on the
rest of the kernel (and since both are exported to modules), make strnicmp
a wrapper for strncasecmp.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 02:18:23 +02:00
Linus Torvalds
72d9310460 Make ARCH_HAS_FAST_MULTIPLIER a real config variable
It used to be an ad-hoc hack defined by the x86 version of
<asm/bitops.h> that enabled a couple of library routines to know whether
an integer multiply is faster than repeated shifts and additions.

This just makes it use the real Kconfig system instead, and makes x86
(which was the only architecture that did this) select the option.

NOTE! Even for x86, this really is kind of wrong.  If we cared, we would
probably not enable this for builds optimized for netburst (P4), where
shifts-and-adds are generally faster than multiplies.  This patch does
*not* change that kind of logic, though, it is purely a syntactic change
with no code changes.

This was triggered by the fact that we have other places that really
want to know "do I want to expand multiples by constants by hand or
not", particularly the hash generation code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-13 11:14:53 -07:00
Dan Carpenter
0046dd9fed lib/string.c: use the name "C-string" in comments
For strncpy() and friends the source string may or may not have an actual
NUL character at the end.  The documentation is confusing in this because
it specifically mentions that you are passing a "NUL-terminated" string.
Wikipedia says that "C-string" is an alternative name we can use instead.

http://en.wikipedia.org/wiki/Null-terminated_string

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:18 -07:00
Grant Likely
11d200e95f lib: add glibc style strchrnul() variant
The strchrnul() variant helpfully returns a the end of the string
instead of a NULL if the requested character is not found. This can
simplify string parsing code since it doesn't need to expicitly check
for a NULL return. If a valid string pointer is passed in, then a valid
null terminated string will always come back out.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
2014-05-23 11:23:27 +09:00
Andi Kleen
a7330c997d asmlinkage Make __stack_chk_failed and memcmp visible
In LTO symbols implicitely referenced by the compiler need
to be visible. Earlier these symbols were visible implicitely
from being exported, but we disabled implicit visibility fo
 EXPORTs when modules are disabled to improve code size. So
now these symbols have to be marked visible explicitely.

Do this for __stack_chk_fail (with stack protector)
and memcmp.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1391845930-28580-10-git-send-email-ak@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-13 18:13:43 -08:00
Linus Torvalds
11bcb32848 Merge tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker:
 "Fix up files in fs/ and lib/ dirs to only use module.h if they really
  need it.

  These are trivial in scope vs the work done previously.  We now have
  things where any few remaining cleanups can be farmed out to arch or
  subsystem maintainers, and I have done so when possible.  What is
  remaining here represents the bits that don't clearly lie within a
  single arch/subsystem boundary, like the fs dir and the lib dir.

  Some duplicate includes arising from overlapping fixes from
  independent subsystem maintainer submissions are also quashed."

Fix up trivial conflicts due to clashes with other include file cleanups
(including some due to the previous bug.h cleanup pull).

* tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  lib: reduce the use of module.h wherever possible
  fs: reduce the use of module.h wherever possible
  includecheck: delete any duplicate instances of module.h
2012-03-24 10:24:31 -07:00
Linus Torvalds
ed2d265d12 Merge tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull <linux/bug.h> cleanup from Paul Gortmaker:
 "The changes shown here are to unify linux's BUG support under the one
  <linux/bug.h> file.  Due to historical reasons, we have some BUG code
  in bug.h and some in kernel.h -- i.e.  the support for BUILD_BUG in
  linux/kernel.h predates the addition of linux/bug.h, but old code in
  kernel.h wasn't moved to bug.h at that time.  As a band-aid, kernel.h
  was including <asm/bug.h> to pseudo link them.

  This has caused confusion[1] and general yuck/WTF[2] reactions.  Here
  is an example that violates the principle of least surprise:

      CC      lib/string.o
      lib/string.c: In function 'strlcat':
      lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
      make[2]: *** [lib/string.o] Error 1
      $
      $ grep linux/bug.h lib/string.c
      #include <linux/bug.h>
      $

  We've included <linux/bug.h> for the BUG infrastructure and yet we
  still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh -
  very confusing for someone who is new to kernel development.

  With the above in mind, the goals of this changeset are:

  1) find and fix any include/*.h files that were relying on the
     implicit presence of BUG code.
  2) find and fix any C files that were consuming kernel.h and hence
     relying on implicitly getting some/all BUG code.
  3) Move the BUG related code living in kernel.h to <linux/bug.h>
  4) remove the asm/bug.h from kernel.h to finally break the chain.

  During development, the order was more like 3-4, build-test, 1-2.  But
  to ensure that git history for bisect doesn't get needless build
  failures introduced, the commits have been reorderd to fix the problem
  areas in advance.

	[1]  https://lkml.org/lkml/2012/1/3/90
	[2]  https://lkml.org/lkml/2012/1/17/414"

Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul
and linux-next.

* tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  kernel.h: doesn't explicitly use bug.h, so don't include it.
  bug: consolidate BUILD_BUG_ON with other bug code
  BUG: headers with BUG/BUG_ON etc. need linux/bug.h
  bug.h: add include of it to various implicit C users
  lib: fix implicit users of kernel.h for TAINT_WARN
  spinlock: macroize assert_spin_locked to avoid bug.h dependency
  x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-24 10:08:39 -07:00
Akinobu Mita
f43804bf5f string: memchr_inv() speed improvements
- Generate a 64-bit pattern more efficiently

memchr_inv needs to generate a 64-bit pattern filled with a target
character.  The operation can be done by more efficient way.

- Don't call the slow check_bytes() if the memory area is 64-bit aligned

memchr_inv compares contiguous 64-bit words with the 64-bit pattern as
much as possible.  The outside of the region is checked by check_bytes()
that scans for each byte.  Unfortunately, the first 64-bit word is
unexpectedly scanned by check_bytes() even if the memory area is aligned
to a 64-bit boundary.

Both changes were originally suggested by Eric Dumazet.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:35 -07:00
Paul Gortmaker
8bc3bcc93a lib: reduce the use of module.h wherever possible
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include.  Fix up any implicit
include dependencies that were being masked by module.h along
the way.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-03-07 15:04:04 -05:00
Paul Gortmaker
50af5ead3b bug.h: add include of it to various implicit C users
With bug.h currently living right in linux/kernel.h there
are files that use BUG_ON and friends but are not including
the header explicitly.  Fix them up so we can remove the
presence in kernel.h file.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-29 17:15:08 -05:00
Michael Holzheu
66f6958e69 lib/string.c: fix strim() semantics for strings that have only blanks
Commit 84c95c9acf ("string: on strstrip(), first remove leading spaces
before running over str") improved the performance of the strim()
function.

Unfortunately this changed the semantics of strim() and broke my code.
Before the patch it was possible to use strim() without using the return
value for removing trailing spaces from strings that had either only
blanks or only trailing blanks.

Now this does not work any longer for strings that *only* have blanks.

Before patch: "   " -> ""    (empty string)
After patch:  "   " -> "   " (no change)

I think we should remove your patch to restore the old behavior.

The description (lib/string.c):

 * Note that the first trailing whitespace is replaced with a %NUL-terminator

=> The first trailing whitespace of a string that only has whitespace
   characters is the first whitespace

The patch restores the old strim() semantics.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Andre Goddard Rosa <andre.goddard@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:56 -07:00
Akinobu Mita
798248206b lib/string.c: introduce memchr_inv()
memchr_inv() is mainly used to check whether the whole buffer is filled
with just a specified byte.

The function name and prototype are stolen from logfs and the
implementation is from SLUB.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: Joern Engel <joern@logfs.org>
Cc: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:47 -07:00
Jonathan Cameron
d0f1fed29e Add a strtobool function matching semantics of existing in kernel equivalents
This is a rename of the usr_strtobool proposal, which was a renamed,
relocated and fixed version of previous kstrtobool RFC

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-05-19 16:55:28 +09:30
André Goddard Rosa
d6a2eedfdd lib/string.c: simplify strnstr()
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Joe Perches <joe@perches.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:35 -08:00
André Goddard Rosa
a11d2b64e1 lib/string.c: simplify stricmp()
Removes 32 bytes on core2 with gcc 4.4.1:
   text    data     bss     dec     hex filename
   3196       0       0    3196     c7c lib/string-BEFORE.o
   3164       0       0    3164     c5c lib/string-AFTER.o

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:35 -08:00
Li Zefan
d5f1fb5335 lib: Introduce strnstr()
It differs strstr() in that it limits the length to be searched
in the first string.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4B4E8743.6030805@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-01-14 22:38:09 -05:00
Randy Dunlap
a6cd13f3c9 lib/string.c: fix kernel-doc warnings
Fix kernel-doc warnings (@arg name) in string.c::skip_spaces().

  Warning(lib/string.c:347): No description found for parameter 'str'
  Warning(lib/string.c:347): Excess function parameter 's' description in 'skip_spaces'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-22 14:17:55 -08:00
KOSAKI Motohiro
ca54cb8c9e Subject: Re: [PATCH] strstrip incorrectly marked __must_check
Recently, We marked strstrip() as must_check.  because it was frequently
misused and it should be checked.  However, we found one exception.
scsi/ipr.c intentionally ignore return value of strstrip.  Because it
wishes to keep the whitespace at the beginning.

Thus we need to keep with and without checked whitespace trim function.
This patch adds a new strim() and changes ipr.c to use it.

[akpm@linux-foundation.org: coding-style fixes]
Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:34 -08:00
André Goddard Rosa
84c95c9acf string: on strstrip(), first remove leading spaces before running over str
... so that strlen() iterates over a smaller string comprising of the
remaining characters only.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:32 -08:00
André Goddard Rosa
f653398c86 string: factorize skip_spaces and export it to be generally available
On the following sentence:
    while (*s && isspace(*s))
        s++;

If *s == 0, isspace() evaluates to ((_ctype[*s] & 0x20) != 0), which
evaluates to ((0x08 & 0x20) != 0) which equals to 0 as well.
If *s == 1, we depend on isspace() result anyway. In other words,
"a char equals zero is never a space", so remove this check.

Also, *s != 0 is most common case (non-null string).

Fixed const return as noticed by Jan Engelhardt and James Bottomley.
Fixed unnecessary extra cast on strstrip() as noticed by Jan Engelhardt.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:32 -08:00
Linus Torvalds
a414f01ac2 strcmp: fix overflow and possibly signedness error
Doing the strcmp return value as

	signed char __res = *cs - *ct;

is wrong for two reasons.  The subtraction can overflow because __res
doesn't use a type big enough.  Moreover the compared bytes should be
interpreted as unsigned char as specified by POSIX.

The same problem is fixed in strncmp.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-18 17:18:13 -08:00
David Brownell
34990cf702 Add a new sysfs_streq() string comparison function
Add a new sysfs_streq() string comparison function, which ignores
the trailing newlines found in sysfs inputs.  By example:

	sysfs_streq("a", "b")	==> false
	sysfs_streq("a", "a")	==> true
	sysfs_streq("a", "a\n")	==> true
	sysfs_streq("a\n", "a")	==> true

This is intended to simplify parsing of sysfs inputs, letting them
avoid the need to manually strip off newlines from inputs.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:03:59 -07:00
David S. Miller
ded220bd8f [STRING]: Move strcasecmp/strncasecmp to lib/string.c
We have several platforms using local copies of identical
code.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 01:54:39 -07:00
Robert P. J. Day
72fd4a35a8 [PATCH] Numerous fixes to kernel-doc info in source files.
A variety of (mostly) innocuous fixes to the embedded kernel-doc content in
source files, including:

  * make multi-line initial descriptions single line
  * denote some function names, constants and structs as such
  * change erroneous opening '/*' to '/**' in a few places
  * reword some text for clarity

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:32 -08:00