When a process updates the RSS of a different process, the rss_stat
tracepoint appears in the context of the process doing the update. This
can confuse userspace that the RSS of process doing the update is
updated, while in reality a different process's RSS was updated.
This issue happens in reclaim paths such as with direct reclaim or
background reclaim.
This patch adds more information to the tracepoint about whether the mm
being updated belongs to the current process's context (curr field). We
also include a hash of the mm pointer so that the process who the mm
belongs to can be uniquely identified (mm_id field).
Borrowed hashing code from upstream for vsprintf.c.
Change-Id: I5bac4aa221cea0d123fdb6fcc15dede6130e9c22
Bug: 140711541
Reported-by: Ioannis Ilkos <ilkos@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Joel Fernandes <joelaf@google.com>
(cherry picked from commit a832417ac5b86b3e5b9f396fd4d053f409bd7628)
Linux 4.4.139
* Bluetooth: Fix connection if directed advertising and privacy is used
include/net/bluetooth/hci_core.h
net/bluetooth/hci_conn.c
net/bluetooth/hci_event.c
* cdc_ncm: avoid padding beyond end of skb
drivers/net/usb/cdc_ncm.c
dm thin: handle running out of data space vs concurrent discard
* block: Fix transfer when chunk sectors exceeds max
include/linux/blkdev.h
* spi: Fix scatterlist elements size in spi_map_buf
drivers/spi/spi.c
* Btrfs: fix unexpected cow in run_delalloc_nocow
fs/btrfs/inode.c
* ALSA: hda/realtek - Add a quirk for FSC ESPRIMO U9210
sound/pci/hda/patch_realtek.c
Input: elantech - fix V4 report decoding for module with middle key
Input: elantech - enable middle button of touchpads on ThinkPad P52
Input: elan_i2c_smbus - fix more potential stack buffer overflows
udf: Detect incorrect directory size
xen: Remove unnecessary BUG_ON from __unbind_from_irq()
Input: elan_i2c - add ELAN0618 (Lenovo v330 15IKB) ACPI ID
video: uvesafb: Fix integer overflow in allocation
* NFSv4: Fix possible 1-byte stack overflow in nfs_idmap_read_and_verify_message
fs/nfs/nfs4idmap.c
* nfsd: restrict rd_maxcount to svc_max_payload in nfsd_encode_readdir
fs/nfsd/nfs4xdr.c
media: dvb_frontend: fix locking issues at dvb_frontend_get_event()
media: cx231xx: Add support for AverMedia DVD EZMaker 7
* media: v4l2-compat-ioctl32: prevent go past max size
drivers/media/v4l2-core/v4l2-compat-ioctl32.c
* perf intel-pt: Fix packet decoding of CYC packets
tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c
* perf intel-pt: Fix "Unexpected indirect branch" error
tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
* perf intel-pt: Fix MTC timing after overflow
tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
* perf intel-pt: Fix decoding to accept CBR between FUP and corresponding TIP
tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
perf intel-pt: Fix sync_switch INTEL_PT_SS_NOT_TRACING
perf tools: Fix symbol and object code resolution for vdso32 and vdsox32
mfd: intel-lpss: Program REMAP register in PIO mode
backlight: tps65217_bl: Fix Device Tree node lookup
backlight: max8925_bl: Fix Device Tree node lookup
backlight: as3711_bl: Fix Device Tree node lookup
* xfrm: skip policies marked as dead while rehashing
net/xfrm/xfrm_policy.c
* xfrm: Ignore socket policies when rebuilding hash tables
net/xfrm/xfrm_policy.c
UBIFS: Fix potential integer overflow in allocation
ubi: fastmap: Cancel work upon detach
* md: fix two problems with setting the "re-add" device state.
drivers/md/md.c
linvdimm, pmem: Preserve read-only setting for pmem devices
scsi: zfcp: fix missing REC trigger trace on enqueue without ERP thread
scsi: zfcp: fix missing REC trigger trace for all objects in ERP_FAILED
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io for ERP_FAILED
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io early return
scsi: zfcp: fix misleading REC trigger trace where erp_action setup failed
scsi: zfcp: fix missing SCSI trace for retry of abort / scsi_eh TMF
scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler
scsi: qla2xxx: Fix setting lower transfer speed if GPSC fails
* iio:buffer: make length types match kfifo types
include/linux/iio/buffer.h
* Btrfs: fix clone vs chattr NODATASUM race
fs/btrfs/ioctl.c
* time: Make sure jiffies_to_msecs() preserves non-zero time periods
kernel/time/time.c
MIPS: io: Add barrier after register read in inX()
PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum
mtd: cfi_cmdset_0002: Avoid walking all chips when unlocking.
mtd: cfi_cmdset_0002: Fix unlocking requests crossing a chip boudary
mtd: cfi_cmdset_0002: fix SEGV unlocking multiple chips
mtd: cfi_cmdset_0002: Use right chip in do_ppb_xxlock()
mtd: cfi_cmdset_0002: Change write buffer to check correct value
RDMA/mlx4: Discard unknown SQP work requests
IB/qib: Fix DMA api warning with debug kernel
of: unittest: for strings, account for trailing \0 in property length field
ARM: 8764/1: kgdb: fix NUMREGBYTES so that gdb_regs[] is the correct size
powerpc/fadump: Unregister fadump on kexec down path.
cpuidle: powernv: Fix promotion from snooze if next state disabled
powerpc/ptrace: Fix enforcement of DAWR constraints
powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG
powerpc/mm/hash: Add missing isync prior to kernel stack SLB switch
* fuse: fix control dir setup and teardown
fs/fuse/control.c
* fuse: don't keep dead fuse_conn at fuse_fill_super().
fs/fuse/inode.c
* fuse: atomic_o_trunc should truncate pagecache
fs/fuse/dir.c
Bluetooth: hci_qca: Avoid missing rampatch failure with userspace fw loader
ipmi:bt: Set the timeout before doing a capabilities check
* branch-check: fix long->int truncation when profiling branches
include/linux/compiler.h
mips: ftrace: fix static function graph tracing
* lib/vsprintf: Remove atomic-unsafe support for %pCr
lib/vsprintf.c
ASoC: cirrus: i2s: Fix {TX|RX}LinCtrlData setup
ASoC: cirrus: i2s: Fix LRCLK configuration
* ASoC: dapm: delete dapm_kcontrol_data paths list before freeing it
sound/soc/soc-dapm.c
1wire: family module autoload fails because of upper/lower case mismatch.
* usb: do not reset if a low-speed or full-speed device timed out
drivers/usb/core/hub.c
signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
* serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding version
drivers/tty/serial/sh-sci.c
m68k/mm: Adjust VM area to be unmapped by gap size for __iounmap()
x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec()
fs/binfmt_misc.c: do not allow offset overflow
w1: mxc_w1: Enable clock before calling clk_get_rate() on it
libata: Drop SanDisk SD7UB3Q*G1001 NOLPM quirk
libata: zpodd: small read overflow in eject_tray()
libata: zpodd: make arrays cdb static, reduces object code size
* cpufreq: Fix new policy initialization during limits updates via sysfs
drivers/cpufreq/cpufreq.c
* ALSA: hda: add dock and led support for HP ProBook 640 G4
sound/pci/hda/patch_conexant.c
* ALSA: hda: add dock and led support for HP EliteBook 830 G5
sound/pci/hda/patch_conexant.c
* ALSA: hda - Handle kzalloc() failure in snd_hda_attach_pcm_stream()
sound/pci/hda/hda_controller.c
btrfs: scrub: Don't use inode pages for device replace
* driver core: Don't ignore class_dir_create_and_add() failure.
drivers/base/core.c
* ext4: fix fencepost error in check for inode count overflow during resize
fs/ext4/resize.c
* ext4: update mtime in ext4_punch_hole even if no blocks are released
fs/ext4/inode.c
* tcp: verify the checksum of the first data segment in a new connection
net/ipv4/tcp_ipv4.c
net/ipv6/tcp_ipv6.c
* bonding: re-evaluate force_primary when the primary slave name changes
drivers/net/bonding/bond_options.c
* usb: musb: fix remote wakeup racing with suspend
drivers/usb/musb/musb_host.c
* Btrfs: make raid6 rebuild retry more
fs/btrfs/volumes.c
* tcp: do not overshoot window_clamp in tcp_rcv_space_adjust()
net/ipv4/tcp_input.c
* Revert "Btrfs: fix scrub to repair raid6 corruption"
fs/btrfs/volumes.c
net/sonic: Use dma_mapping_error()
net: qmi_wwan: Add Netgear Aircard 779S
atm: zatm: fix memcmp casting
* ipvs: fix buffer overflow with sync daemon and service
net/netfilter/ipvs/ip_vs_ctl.c
* netfilter: ebtables: handle string from userspace with care
net/bridge/netfilter/ebtables.c
* xfrm6: avoid potential infinite loop in _decode_session6()
net/ipv6/xfrm6_policy.c
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Add %paP and %padP for physical address that need to always be shown
regardless of kptr restrictions.
Bug: 37723342
Bug: 30368199
Change-Id: I4884854d9465be89f366d4d7b56c825918b91599
Signed-off-by: Chris Fries <cfries@google.com>
Set the initial value of kptr_restrict to the maximum
setting rather than the minimum setting, to ensure that
early boot logging is not leaking information.
BUG: 30368199
Change-Id: I2c13a223d7175ae27683c5f7873a65fac8e3122e
Signed-off-by: Dave Weinstein <olorin@google.com>
Add the kptr_restrict setting of 4 which results in %pa and
%p[rR] values being replaced by zeros.
BUG: 30368199
Change-Id: Ia7bc34a7da714d8111ee41e7d38d1cd3eff1cb71
Signed-off-by: Dave Weinstein <olorin@google.com>
Add the kptr_restrict setting of 3 which results in both
%p and %pK values being replaced by zeros.
Add an additional %pP value inspired by the Grsecurity
option which explicitly whitelists pointers for output.
This patch is based on work by William Roberts
<william.c.roberts@intel.com>
BUG: 30368199
Change-Id: I54b53375d69aee09ace7c891d637a9dfe56f0fd7
Signed-off-by: Dave Weinstein <olorin@google.com>
Set the initial value of kptr_restrict to the maximum
setting rather than the minimum setting, to ensure that
early boot logging is not leaking information.
BUG: 30368199
Change-Id: If738e3b2ff85b737127daf16f2f3a722e616f389
Signed-off-by: Dave Weinstein <olorin@google.com>
Add the kptr_restrict setting of 4 which results in %pa and
%p[rR] values being replaced by zeros.
BUG: 30368199
Change-Id: I2cfac7cd0d9c05dbad07c683fac79aea8c2ba59d
Signed-off-by: Dave Weinstein <olorin@google.com>
Add the kptr_restrict setting of 3 which results in both
%p and %pK values being replaced by zeros.
Add an additional %pP value inspired by the Grsecurity
option which explicitly whitelists pointers for output.
This patch is based on work by William Roberts
<william.c.roberts@intel.com>
BUG: 30368199
Change-Id: Ic5cef86617f7758514271edd67199683d2c4e2bb
Signed-off-by: Dave Weinstein <olorin@google.com>
As a quick
git grep -E '%[ +0#-]*#[ +0#-]*(\*|[0-9]+)?(\.(\*|[0-9]+)?)?p'
shows, nobody uses the # flag with %p. Should one try to do so, one
will be met with
warning: `#' flag used with `%p' gnu_printf format [-Wformat]
(POSIX and C99 both say "... For other conversion specifiers, the
behavior is undefined.". Obviously, the kernel can choose to define
the behaviour however it wants, but as long as gcc issues that
warning, users are unlikely to show up.)
Since default_width is effectively always 2*sizeof(void*), we can
simplify the prologue of pointer() and save a few instructions.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Martin Kletzander <mkletzan@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Quoting from 2aa2f9e21e ("lib/vsprintf.c: improve sanity check in
vsnprintf()"):
On 64 bit, size may very well be huge even if bit 31 happens to be 0.
Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a
3 GiB one. So cap at INT_MAX as was probably the intention all along.
This is also the made-up value passed by sprintf and vsprintf.
I should have seen this copy-pasted instance back then, but let's just
do it now.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Martin Kletzander <mkletzan@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we meet any invalid or unsupported format specifier, 'handling' it by
just printing it as a literal string is not safe: Presumably the format
string and the arguments passed gcc's type checking, but that means
something like sprintf(buf, "%n %pd", &intvar, dentry) would end up
interpreting &intvar as a struct dentry*.
When the offending specifier was %n it used to be at the end of the format
string, but we can't rely on that always being the case. Also, gcc
doesn't complain about some more or less exotic qualifiers (or 'length
modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by
the kernel's printf implementation, they'd be interpreted as unknown
specifiers, and the rest of arguments would be interpreted wrongly.
So let's complain about anything we don't understand, not just %n, and
stop pretending that we'd be able to make sense of the rest of the
format/arguments. If the offending specifier is in a printk() call we
unfortunately only get a "BUG: recent printk recursion!", but at least
direct users of the sprintf family will be caught.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Martin Kletzander <mkletzan@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move all pointer-formatting documentation to one place in the code and one
place in the documentation instead of keeping it in three places with
different level of completeness. Documentation/printk-formats.txt has
detailed information about each modifier, docstring above pointer() has
short descriptions of them (as that is the function dealing with %p) and
docstring above vsprintf() is removed as redundant. Both docstrings in
the code that were modified are updated with a reminder of updating the
documentation upon any further change.
[akpm@linux-foundation.org: fix comment]
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file uses the clk API so it should include clk.h directly
instead of indirectly including it through clk-provider.h.
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
I hadn't had enough coffee when I wrote this. Currently, the final
increment of buf depends on the value loaded from the table, and
causes gcc to emit a cmov immediately before the return. It is smarter
to let it depend on r, since the increment can then be computed in
parallel with the final load/store pair. It also shaves 16 bytes of
.text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The most expensive part of decimal conversion is the divisions by 10
(albeit done using reciprocal multiplication with appropriately chosen
constants). I decided to see if one could eliminate around half of
these multiplications by emitting two digits at a time, at the cost of a
200 byte lookup table, and it does indeed seem like there is something
to be gained, especially on 64 bits. Microbenchmarking shows
improvements ranging from -50% (for numbers uniformly distributed in [0,
2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a
more realistic distribution).
On a larger scale, perf shows that top, one of the big consumers of /proc
data, uses 0.5-1.0% fewer cpu cycles.
I had to jump through some hoops to get the 32 bit code to compile and run
on my 64 bit machine, so I'm not sure how relevant these numbers are, but
just for comparison the microbenchmark showed improvements between -30%
and -10%.
The bloat-o-meter costs are around 150 bytes (the generated code is a
little smaller, so it's not the full 200 bytes) on both 32 and 64 bit.
I'm aware that extra cache misses won't show up in a microbenchmark as
used above, but on the other hand decimal conversions often happen in bulk
(for example in the case of top).
I have of course tested that the new code generates the same output as the
old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9
'random' numbers in-between.
Test and verification code on github: https://github.com/Villemoes/dec.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Tested-by: Jeff Epler <jepler@unpythonic.net>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.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>
The current semantics of string_escape_mem are inadequate for one of its
current users, vsnprintf(). If that is to honour its contract, it must
know how much space would be needed for the entire escaped buffer, and
string_escape_mem provides no way of obtaining that (short of allocating a
large enough buffer (~4 times input string) to let it play with, and
that's definitely a big no-no inside vsnprintf).
So change the semantics for string_escape_mem to be more snprintf-like:
Return the size of the output that would be generated if the destination
buffer was big enough, but of course still only write to the part of dst
it is allowed to, and (contrary to snprintf) don't do '\0'-termination.
It is then up to the caller to detect whether output was truncated and to
append a '\0' if desired. Also, we must output partial escape sequences,
otherwise a call such as snprintf(buf, 3, "%1pE", "\123") would cause
printf to write a \0 to buf[2] but leaving buf[0] and buf[1] with whatever
they previously contained.
This also fixes a bug in the escaped_string() helper function, which used
to unconditionally pass a length of "end-buf" to string_escape_mem();
since the latter doesn't check osz for being insanely large, it would
happily write to dst. For example, kasprintf(GFP_KERNEL, "something and
then %pE", ...); is an easy way to trigger an oops.
In test-string_helpers.c, the -ENOMEM test is replaced with testing for
getting the expected return value even if the buffer is too small. We
also ensure that nothing is written (by relying on a NULL pointer deref)
if the output size is 0 by passing NULL - this has to work for
kasprintf("%pE") to work.
In net/sunrpc/cache.c, I think qword_add still has the same semantics.
Someone should definitely double-check this.
In fs/proc/array.c, I made the minimum possible change, but longer-term it
should stop poking around in seq_file internals.
[andriy.shevchenko@linux.intel.com: simplify qword_add]
[andriy.shevchenko@linux.intel.com: add missed curly braces]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
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>
The helper hex_string() is broken in two ways. First, it doesn't
increment buf regardless of whether there is room to print, so callers
such as kasprintf() that try to probe the correct storage to allocate will
get a too small return value. But even worse, kasprintf() (and likely
anyone else trying to find the size of the result) pass NULL for buf and 0
for size, so we also have end == NULL. But this means that the end-1 in
hex_string() is (char*)-1, so buf < end-1 is true and we get a NULL
pointer deref. I double-checked this with a trivial kernel module that
just did a kasprintf(GFP_KERNEL, "%14ph", "CrashBoomBang").
Nobody seems to be using %ph with kasprintf, but we might as well fix it
before it hits someone.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-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>
Add format specifiers for printing struct clk:
- '%pC' or '%pCn': name (Common Clock Framework) or address (legacy
clock framework) of the clock,
- '%pCr': rate of the clock.
[akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc doesn't merge or overlap const char[] objects with identical contents
(probably language lawyers would also insist that these things have
different addresses), but there's no reason to have the string
"0123456789ABCDEF" occur in multiple places. hex_asc_upper is declared in
kernel.h and defined in lib/hexdump.c, which is unconditionally compiled
in.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At least since the initial git commit, when base was passed as a separate
parameter, number() has only been called with bases 8, 10 and 16. I'm
guessing that 66 was to accommodate 64 0/1, a sign and a '\0', but the
buffer is only used for the actual digits. Octal digits carry 3 bits of
information, so 24 is enough. Spell that 3*sizeof(num) so one less place
needs to be changed should long long ever be 128 bits. Also remove the
commented-out code that would handle an arbitrary base.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and
similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few
instructions by making SIGN have the value 1 instead of 2, and then use
arithmetic instead of branches for computing the right spec->type. It's a
little hacky, but certainly in the same spirit as SMALL needing to have
the value 0x20. For example for the spec->qualifier == 'l' case, gcc now
generates
75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx
762: 83 e2 01 and $0x1,%edx
765: 83 c2 09 add $0x9,%edx
768: 88 13 mov %dl,(%rbx)
instead of
763: 0f b6 53 01 movzbl 0x1(%rbx),%edx
767: 83 e2 02 and $0x2,%edx
76a: 80 fa 01 cmp $0x1,%dl
76d: 19 d2 sbb %edx,%edx
76f: 83 c2 0a add $0xa,%edx
772: 88 13 mov %dl,(%rbx)
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bitmap and its derivatives such as cpumask and nodemask currently only
provide formatting functions which put the output string into the
provided buffer; however, how long this buffer should be isn't defined
anywhere and given that some of these bitmaps can be too large to be
formatted into an on-stack buffer it users sometimes are unnecessarily
forced to come up with creative solutions and compromises for the
buffer just to printk these bitmaps.
There have been a couple different attempts at making this easier.
1. Way back, PeterZ tried printk '%pb' extension with the precision
for bit width - '%.*pb'. This was intuitive and made sense but
unfortunately triggered a compile warning about using precision
for a pointer.
http://lkml.kernel.org/g/1336577562.2527.58.camel@twins
2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask
and nodemask. This works but PeterZ pointed out that pr_cont's
tendency to produce broken lines when multiple CPUs are printing is
bothering considering the usages.
http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org
So, this patch is another attempt at teaching printk and friends how
to print bitmaps. It's almost identical to what PeterZ tried with
precision but it uses the field width for the number of bits instead
of precision. The format used is '%*pb[l]', with the optional
trailing 'l' specifying list format instead of hex masks.
This is a valid format string and doesn't trigger compiler warnings;
however, it does make it impossible to specify output field width when
printing bitmaps. I think this is an acceptable trade-off given how
much easier it makes printing bitmaps and that we don't have any
in-kernel user which is using the field width specification. If any
future user wants to use field width with a bitmap, it'd have to
format the bitmap into a string buffer and then print that buffer with
width spec, which isn't different from how it should be done now.
This patch implements bitmap[_list]_string() which are called from the
vsprintf pointer() formatting function. The implementation is mostly
identical to bitmap_scn[list]printf() except that the output is
performed in the vsprintf way. These functions handle formatting into
too small buffers and sprintf() family of functions report the correct
overrun output length.
bitmap_scn[list]printf() are now thin wrappers around scnprintf().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On 64 bit, size may very well be huge even if bit 31 happens to be 0.
Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a
3 GiB one. So cap at INT_MAX as was probably the intention all along.
This is also the made-up value passed by sprintf and vsprintf.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows user to print a given buffer as an escaped string. The
rules are applied according to an optional mix of flags provided by
additional format letters.
For example, if the given buffer is:
1b 62 20 5c 43 07 22 90 0d 5d
The result strings would be:
%*pE "\eb \C\a"\220\r]"
%*pEhp "\x1bb \C\x07"\x90\x0d]"
%*pEa "\e\142\040\\\103\a\042\220\r\135"
Please, read Documentation/printk-formats.txt and lib/string_helpers.c
kernel documentation to get further information.
[akpm@linux-foundation.org: tidy up comment layout, per Joe]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Joe Perches <joe@perches.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fix spelling typo found in DocBook/kernel-api.xml.
It is because the file is generated from the source comments,
I have to fix the comments in source codes.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Fixing 2 coccinelle warnings:
lib/vsprintf.c:2350:2-9: WARNING: Assignment of bool to 0/1
lib/vsprintf.c:2389:3-10: WARNING: Assignment of bool to 0/1
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All in-kernel users of %n in format strings have now been removed and
the %n directive is ignored. Remove the handling of %n so that it is
treated the same as any other invalid format string directive. Keep a
warning in place to deter new instances of %n in format strings.
Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sometimes we have a struct resource where we know the type (MEM/IO/etc.)
and the size, but we haven't assigned address space for it. The
IORESOURCE_UNSET flag is a way to indicate this situation. For these
"unset" resources, the start address is meaningless, so print only the
size, e.g.,
- pci 0000:0c:00.0: reg 184: [mem 0x00000000-0x00001fff 64bit]
+ pci 0000:0c:00.0: reg 184: [mem size 0x2000 64bit]
For %pr (printing with raw flags), we still print the address range,
because %pr is mostly used for debugging anyway.
Thanks to Fengguang Wu <fengguang.wu@intel.com> for suggesting
resource_size().
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This ignores %n in printf again, as was originally documented.
Implementing %n poses a greater security risk than utility, so it should
stay ignored. To help anyone attempting to use %n, a warning will be
emitted if it is encountered.
Based on an earlier patch by Joe Perches.
Because %n was designed to write to pointers on the stack, it has been
frequently used as an attack vector when bugs are found that leak
user-controlled strings into functions that ultimately process format
strings. While this class of bug can still be turned into an
information leak, removing %n eliminates the common method of elevating
such a bug into an arbitrary kernel memory writing primitive,
significantly reducing the danger of this class of bug.
For seq_file users that need to know the length of a written string for
padding, please see seq_setwidth() and seq_pad() instead.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some setuid binaries will allow reading of files which have read
permission by the real user id. This is problematic with files which
use %pK because the file access permission is checked at open() time,
but the kptr_restrict setting is checked at read() time. If a setuid
binary opens a %pK file as an unprivileged user, and then elevates
permissions before reading the file, then kernel pointer values may be
leaked.
This happens for example with the setuid pppd application on Ubuntu 12.04:
$ head -1 /proc/kallsyms
00000000 T startup_32
$ pppd file /proc/kallsyms
pppd: In file /proc/kallsyms: unrecognized option 'c1000000'
This will only leak the pointer value from the first line, but other
setuid binaries may leak more information.
Fix this by adding a check that in addition to the current process having
CAP_SYSLOG, that effective user and group ids are equal to the real ids.
If a setuid binary reads the contents of a file which uses %pK then the
pointer values will be printed as NULL if the real user is unprivileged.
Update the sysctl documentation to reflect the changes, and also correct
the documentation to state the kptr_restrict=0 is the default.
This is a only temporary solution to the issue. The correct solution is
to do the permission check at open() time on files, and to replace %pK
with a function which checks the open() time permission. %pK uses in
printk should be removed since no sane permission check can be done, and
instead protected by using dmesg_restrict.
Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Joe Perches <joe@perches.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry *
or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s)
of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull networking updates from David Miller:
"This is a re-do of the net-next pull request for the current merge
window. The only difference from the one I made the other day is that
this has Eliezer's interface renames and the timeout handling changes
made based upon your feedback, as well as a few bug fixes that have
trickeled in.
Highlights:
1) Low latency device polling, eliminating the cost of interrupt
handling and context switches. Allows direct polling of a network
device from socket operations, such as recvmsg() and poll().
Currently ixgbe, mlx4, and bnx2x support this feature.
Full high level description, performance numbers, and design in
commit 0a4db187a9 ("Merge branch 'll_poll'")
From Eliezer Tamir.
2) With the routing cache removed, ip_check_mc_rcu() gets exercised
more than ever before in the case where we have lots of multicast
addresses. Use a hash table instead of a simple linked list, from
Eric Dumazet.
3) Add driver for Atheros CQA98xx 802.11ac wireless devices, from
Bartosz Markowski, Janusz Dziedzic, Kalle Valo, Marek Kwaczynski,
Marek Puzyniak, Michal Kazior, and Sujith Manoharan.
4) Support reporting the TUN device persist flag to userspace, from
Pavel Emelyanov.
5) Allow controlling network device VF link state using netlink, from
Rony Efraim.
6) Support GRE tunneling in openvswitch, from Pravin B Shelar.
7) Adjust SOCK_MIN_RCVBUF and SOCK_MIN_SNDBUF for modern times, from
Daniel Borkmann and Eric Dumazet.
8) Allow controlling of TCP quickack behavior on a per-route basis,
from Cong Wang.
9) Several bug fixes and improvements to vxlan from Stephen
Hemminger, Pravin B Shelar, and Mike Rapoport. In particular,
support receiving on multiple UDP ports.
10) Major cleanups, particular in the area of debugging and cookie
lifetime handline, to the SCTP protocol code. From Daniel
Borkmann.
11) Allow packets to cross network namespaces when traversing tunnel
devices. From Nicolas Dichtel.
12) Allow monitoring netlink traffic via AF_PACKET sockets, in a
manner akin to how we monitor real network traffic via ptype_all.
From Daniel Borkmann.
13) Several bug fixes and improvements for the new alx device driver,
from Johannes Berg.
14) Fix scalability issues in the netem packet scheduler's time queue,
by using an rbtree. From Eric Dumazet.
15) Several bug fixes in TCP loss recovery handling, from Yuchung
Cheng.
16) Add support for GSO segmentation of MPLS packets, from Simon
Horman.
17) Make network notifiers have a real data type for the opaque
pointer that's passed into them. Use this to properly handle
network device flag changes in arp_netdev_event(). From Jiri
Pirko and Timo Teräs.
18) Convert several drivers over to module_pci_driver(), from Peter
Huewe.
19) tcp_fixup_rcvbuf() can loop 500 times over loopback, just use a
O(1) calculation instead. From Eric Dumazet.
20) Support setting of explicit tunnel peer addresses in ipv6, just
like ipv4. From Nicolas Dichtel.
21) Protect x86 BPF JIT against spraying attacks, from Eric Dumazet.
22) Prevent a single high rate flow from overruning an individual cpu
during RX packet processing via selective flow shedding. From
Willem de Bruijn.
23) Don't use spinlocks in TCP md5 signing fast paths, from Eric
Dumazet.
24) Don't just drop GSO packets which are above the TBF scheduler's
burst limit, chop them up so they are in-bounds instead. Also
from Eric Dumazet.
25) VLAN offloads are missed when configured on top of a bridge, fix
from Vlad Yasevich.
26) Support IPV6 in ping sockets. From Lorenzo Colitti.
27) Receive flow steering targets should be updated at poll() time
too, from David Majnemer.
28) Fix several corner case regressions in PMTU/redirect handling due
to the routing cache removal, from Timo Teräs.
29) We have to be mindful of ipv4 mapped ipv6 sockets in
upd_v6_push_pending_frames(). From Hannes Frederic Sowa.
30) Fix L2TP sequence number handling bugs, from James Chapman."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1214 commits)
drivers/net: caif: fix wrong rtnl_is_locked() usage
drivers/net: enic: release rtnl_lock on error-path
vhost-net: fix use-after-free in vhost_net_flush
net: mv643xx_eth: do not use port number as platform device id
net: sctp: confirm route during forward progress
virtio_net: fix race in RX VQ processing
virtio: support unlocked queue poll
net/cadence/macb: fix bug/typo in extracting gem_irq_read_clear bit
Documentation: Fix references to defunct linux-net@vger.kernel.org
net/fs: change busy poll time accounting
net: rename low latency sockets functions to busy poll
bridge: fix some kernel warning in multicast timer
sfc: Fix memory leak when discarding scattered packets
sit: fix tunnel update via netlink
dt:net:stmmac: Add dt specific phy reset callback support.
dt:net:stmmac: Add support to dwmac version 3.610 and 3.710
dt:net:stmmac: Allocate platform data only if its NULL.
net:stmmac: fix memleak in the open method
ipv6: rt6_check_neigh should successfully verify neigh if no NUD information are available
net: ipv6: fix wrong ping_v6_sendmsg return value
...
In order to avoid making code that deals with printing both, IPv4 and
IPv6 addresses, unnecessary complicated as for example ...
if (sa.sa_family == AF_INET6)
printk("... %pI6 ...", ..sin6_addr);
else
printk("... %pI4 ...", ..sin_addr.s_addr);
... it would be better to introduce a format specifier that can deal
with those kind of situations internally; just as we have a "struct
sockaddr" for generic mapping into "struct sockaddr_in" or "struct
sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could
reduce the above statement into something like:
printk("... %pIS ..", &sockaddr);
In case our pointer is NULL, pointer() then deals with that already at
an earlier point in time internally. While we're at it, support for both
%piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free.
Additionally to that, postfix specifiers 'p', 'f' and 's' are supported
as suggested and initially implemented in 2009 by Joe Perches [1].
Handling of those additional specifiers orientate on the initial RFC that
was proposed. Also we support IPv6 compressed format specified by 'c' and
various other IPv4 extensions as stated in the documentation part.
Likely, there are many other areas than just SCTP in the kernel to make
use of this extension as well.
[1] http://patchwork.ozlabs.org/patch/31480/
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
CC: Joe Perches <joe@perches.com>
CC: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
print_symbol takes a long and converts it to a function
name and offset. %pS does something similar, but doesn't
translate the address via __builtin_extract_return_addr.
%pSR does the translation.
This will enable replacing multiple calls like
printk(...);
printk_symbol(addr);
printk("\n");
with a single non-interleavable in dmesg
printk("... %pSR\n", (void *)addr);
Update documentation too.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This is another step towards better standard conformance. Rather than
adding a local buffer to store the specified portion of the string (with
the need to enforce an arbitrary maximum supported width to limit the
buffer size), do a maximum width conversion and then drop as much of it as
is necessary to meet the caller's request.
Also fail on negative field widths.
Uses the deprecated simple_strto*() functions because kstrtoXX() fail on
non-zero terminated strings.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Documentation/printk-formats.txt says to use %zd for a ssize_t argument
and some drivers do. Unfortunately this prints a positive number for
negative values eg:
tpm_tis 70030000.tpm_tis: tpm_transmit: tpm_send: error 4294967234
Add a case to va_args a ssize_t type if the interpretation should be
signed.
Tested on PPC32.
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
