Commit Graph

932 Commits

Author SHA1 Message Date
Mauro (mdrjr) Ribeiro
d7dabe31af Merge tag 'v4.9.274' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
Linux 4.9.274
2021-07-30 21:02:29 -03:00
Mauro (mdrjr) Ribeiro
5bdadab9f1 Merge tag 'v4.9.273' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.273 stable release

Change-Id: I4c404d66b978c06106bd4ae293a155b83733756e
2021-07-30 20:56:39 -03:00
Mauro (mdrjr) Ribeiro
049486e38b Merge tag 'v4.9.269' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.269 stable release

Change-Id: If6f90ebf565306169443fc56ac36f4bc150c524f
2021-07-30 20:48:51 -03:00
Mauro (mdrjr) Ribeiro
76bc91d96a Merge tag 'v4.9.265' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.265 stable release

Change-Id: Ie748f79adf441d896fb2032cf63d699b06f3f908
2021-07-30 20:48:27 -03:00
Mauro (mdrjr) Ribeiro
82c8dea85f Merge tag 'v4.9.258' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.258 stable release

Change-Id: Ibf7f2a97a8bad31d60fa7727fa94e3f5535bfec3
2021-07-30 20:21:00 -03:00
Mauro (mdrjr) Ribeiro
03ab15286e Merge tag 'v4.9.248' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.248 stable release

Change-Id: I5a4a6fb20b838fbd36a7533b6801b7100c01ddef
2021-07-30 20:13:58 -03:00
Mauro (mdrjr) Ribeiro
07f34f8121 Merge tag 'v4.9.242' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.242 stable release
2021-07-30 20:12:57 -03:00
Steven Rostedt (VMware)
54657108d1 tracing: Do not stop recording comms if the trace file is being read
commit 4fdd595e4f upstream.

A while ago, when the "trace" file was opened, tracing was stopped, and
code was added to stop recording the comms to saved_cmdlines, for mapping
of the pids to the task name.

Code has been added that only records the comm if a trace event occurred,
and there's no reason to not trace it if the trace file is opened.

Cc: stable@vger.kernel.org
Fixes: 7ffbd48d5c ("tracing: Cache comms only after an event occurred")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-30 08:49:18 -04:00
Steven Rostedt (VMware)
46ac8f9c1d tracing: Do not stop recording cmdlines when tracing is off
commit 85550c83da upstream.

The saved_cmdlines is used to map pids to the task name, such that the
output of the tracing does not just show pids, but also gives a human
readable name for the task.

If the name is not mapped, the output looks like this:

    <...>-1316          [005] ...2   132.044039: ...

Instead of this:

    gnome-shell-1316    [005] ...2   132.044039: ...

The names are updated when tracing is running, but are skipped if tracing
is stopped. Unfortunately, this stops the recording of the names if the
top level tracer is stopped, and not if there's other tracers active.

The recording of a name only happens when a new event is written into a
ring buffer, so there is no need to test if tracing is on or not. If
tracing is off, then no event is written and no need to test if tracing is
off or not.

Remove the check, as it hides the names of tasks for events in the
instance buffers.

Cc: stable@vger.kernel.org
Fixes: 7ffbd48d5c ("tracing: Cache comms only after an event occurred")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-30 08:49:18 -04:00
Liangyan
edcce01e0e tracing: Correct the length check which causes memory corruption
commit 3e08a9f976 upstream.

We've suffered from severe kernel crashes due to memory corruption on
our production environment, like,

Call Trace:
[1640542.554277] general protection fault: 0000 [#1] SMP PTI
[1640542.554856] CPU: 17 PID: 26996 Comm: python Kdump: loaded Tainted:G
[1640542.556629] RIP: 0010:kmem_cache_alloc+0x90/0x190
[1640542.559074] RSP: 0018:ffffb16faa597df8 EFLAGS: 00010286
[1640542.559587] RAX: 0000000000000000 RBX: 0000000000400200 RCX:
0000000006e931bf
[1640542.560323] RDX: 0000000006e931be RSI: 0000000000400200 RDI:
ffff9a45ff004300
[1640542.560996] RBP: 0000000000400200 R08: 0000000000023420 R09:
0000000000000000
[1640542.561670] R10: 0000000000000000 R11: 0000000000000000 R12:
ffffffff9a20608d
[1640542.562366] R13: ffff9a45ff004300 R14: ffff9a45ff004300 R15:
696c662f65636976
[1640542.563128] FS:  00007f45d7c6f740(0000) GS:ffff9a45ff840000(0000)
knlGS:0000000000000000
[1640542.563937] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1640542.564557] CR2: 00007f45d71311a0 CR3: 000000189d63e004 CR4:
00000000003606e0
[1640542.565279] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[1640542.566069] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[1640542.566742] Call Trace:
[1640542.567009]  anon_vma_clone+0x5d/0x170
[1640542.567417]  __split_vma+0x91/0x1a0
[1640542.567777]  do_munmap+0x2c6/0x320
[1640542.568128]  vm_munmap+0x54/0x70
[1640542.569990]  __x64_sys_munmap+0x22/0x30
[1640542.572005]  do_syscall_64+0x5b/0x1b0
[1640542.573724]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[1640542.575642] RIP: 0033:0x7f45d6e61e27

James Wang has reproduced it stably on the latest 4.19 LTS.
After some debugging, we finally proved that it's due to ftrace
buffer out-of-bound access using a debug tool as follows:
[   86.775200] BUG: Out-of-bounds write at addr 0xffff88aefe8b7000
[   86.780806]  no_context+0xdf/0x3c0
[   86.784327]  __do_page_fault+0x252/0x470
[   86.788367]  do_page_fault+0x32/0x140
[   86.792145]  page_fault+0x1e/0x30
[   86.795576]  strncpy_from_unsafe+0x66/0xb0
[   86.799789]  fetch_memory_string+0x25/0x40
[   86.804002]  fetch_deref_string+0x51/0x60
[   86.808134]  kprobe_trace_func+0x32d/0x3a0
[   86.812347]  kprobe_dispatcher+0x45/0x50
[   86.816385]  kprobe_ftrace_handler+0x90/0xf0
[   86.820779]  ftrace_ops_assist_func+0xa1/0x140
[   86.825340]  0xffffffffc00750bf
[   86.828603]  do_sys_open+0x5/0x1f0
[   86.832124]  do_syscall_64+0x5b/0x1b0
[   86.835900]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

commit b220c049d5 ("tracing: Check length before giving out
the filter buffer") adds length check to protect trace data
overflow introduced in 0fc1b09ff1, seems that this fix can't prevent
overflow entirely, the length check should also take the sizeof
entry->array[0] into account, since this array[0] is filled the
length of trace data and occupy addtional space and risk overflow.

Link: https://lkml.kernel.org/r/20210607125734.1770447-1-liangyan.peng@linux.alibaba.com

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Xunlei Pang <xlpang@linux.alibaba.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: b220c049d5 ("tracing: Check length before giving out the filter buffer")
Reviewed-by: Xunlei Pang <xlpang@linux.alibaba.com>
Reviewed-by: yinbinbin <yinbinbin@alibabacloud.com>
Reviewed-by: Wetp Zhang <wetp.zy@linux.alibaba.com>
Tested-by: James Wang <jnwang@linux.alibaba.com>
Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-16 11:36:36 +02:00
Steven Rostedt (VMware)
e1bf31b76c tracing: Map all PIDs to command lines
commit 785e3c0a3a upstream.

The default max PID is set by PID_MAX_DEFAULT, and the tracing
infrastructure uses this number to map PIDs to the comm names of the
tasks, such output of the trace can show names from the recorded PIDs in
the ring buffer. This mapping is also exported to user space via the
"saved_cmdlines" file in the tracefs directory.

But currently the mapping expects the PIDs to be less than
PID_MAX_DEFAULT, which is the default maximum and not the real maximum.
Recently, systemd will increases the maximum value of a PID on the system,
and when tasks are traced that have a PID higher than PID_MAX_DEFAULT, its
comm is not recorded. This leads to the entire trace to have "<...>" as
the comm name, which is pretty useless.

Instead, keep the array mapping the size of PID_MAX_DEFAULT, but instead
of just mapping the index to the comm, map a mask of the PID
(PID_MAX_DEFAULT - 1) to the comm, and find the full PID from the
map_cmdline_to_pid array (that already exists).

This bug goes back to the beginning of ftrace, but hasn't been an issue
until user space started increasing the maximum value of PIDs.

Link: https://lkml.kernel.org/r/20210427113207.3c601884@gandalf.local.home

Cc: stable@vger.kernel.org
Fixes: bc0c38d139 ("ftrace: latency tracer infrastructure")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-22 10:40:21 +02:00
Amey Telawane
27b1e95a93 tracing: Use strlcpy() instead of strcpy() in __trace_find_cmdline()
commit e09e28671c upstream.

Strcpy is inherently not safe, and strlcpy() should be used instead.
__trace_find_cmdline() uses strcpy() because the comms saved must have a
terminating nul character, but it doesn't hurt to add the extra protection
of using strlcpy() instead of strcpy().

Link: http://lkml.kernel.org/r/1493806274-13936-1-git-send-email-amit.pundir@linaro.org

Signed-off-by: Amey Telawane <ameyt@codeaurora.org>
[AmitP: Cherry-picked this commit from CodeAurora kernel/msm-3.10
https://source.codeaurora.org/quic/la/kernel/msm-3.10/commit/?id=2161ae9a70b12cf18ac8e5952a20161ffbccb477]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
[ Updated change log and removed the "- 1" from len parameter ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-22 10:40:21 +02:00
Joel Fernandes
e17731c2fd tracing: Treat recording comm for idle task as a success
commit eaf260ac04 upstream.

Currently we stop recording comm for non-idle tasks when switching from/to idle
task since we treat that as a record failure. Fix that by treat recording of
comm for idle task as a success.

Link: http://lkml.kernel.org/r/20170706230023.17942-1-joelaf@google.com

Cc: kernel-team@android.com
Cc: Ingo Molnar <mingo@redhat.com>
Reported-by: Michael Sartain <mikesart@gmail.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-22 10:40:21 +02:00
Steven Rostedt (VMware)
5a04620a72 tracing: Fix stack trace event size
commit 9deb193af6 upstream.

Commit cbc3b92ce0 fixed an issue to modify the macros of the stack trace
event so that user space could parse it properly. Originally the stack
trace format to user space showed that the called stack was a dynamic
array. But it is not actually a dynamic array, in the way that other
dynamic event arrays worked, and this broke user space parsing for it. The
update was to make the array look to have 8 entries in it. Helper
functions were added to make it parse it correctly, as the stack was
dynamic, but was determined by the size of the event stored.

Although this fixed user space on how it read the event, it changed the
internal structure used for the stack trace event. It changed the array
size from [0] to [8] (added 8 entries). This increased the size of the
stack trace event by 8 words. The size reserved on the ring buffer was the
size of the stack trace event plus the number of stack entries found in
the stack trace. That commit caused the amount to be 8 more than what was
needed because it did not expect the caller field to have any size. This
produced 8 entries of garbage (and reading random data) from the stack
trace event:

          <idle>-0       [002] d... 1976396.837549: <stack trace>
 => trace_event_raw_event_sched_switch
 => __traceiter_sched_switch
 => __schedule
 => schedule_idle
 => do_idle
 => cpu_startup_entry
 => secondary_startup_64_no_verify
 => 0xc8c5e150ffff93de
 => 0xffff93de
 => 0
 => 0
 => 0xc8c5e17800000000
 => 0x1f30affff93de
 => 0x00000004
 => 0x200000000

Instead, subtract the size of the caller field from the size of the event
to make sure that only the amount needed to store the stack trace is
reserved.

Link: https://lore.kernel.org/lkml/your-ad-here.call-01617191565-ext-9692@work.hours/

Cc: stable@vger.kernel.org
Fixes: cbc3b92ce0 ("tracing: Set kernel_stack's caller size properly")
Reported-by: Vasily Gorbik <gor@linux.ibm.com>
Tested-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-07 12:05:40 +02:00
Steven Rostedt (VMware)
2e584b1a02 tracing: Check length before giving out the filter buffer
commit b220c049d5 upstream.

When filters are used by trace events, a page is allocated on each CPU and
used to copy the trace event fields to this page before writing to the ring
buffer. The reason to use the filter and not write directly into the ring
buffer is because a filter may discard the event and there's more overhead
on discarding from the ring buffer than the extra copy.

The problem here is that there is no check against the size being allocated
when using this page. If an event asks for more than a page size while being
filtered, it will get only a page, leading to the caller writing more that
what was allocated.

Check the length of the request, and if it is more than PAGE_SIZE minus the
header default back to allocating from the ring buffer directly. The ring
buffer may reject the event if its too big anyway, but it wont overflow.

Link: https://lore.kernel.org/ath10k/1612839593-2308-1-git-send-email-wgong@codeaurora.org/

Cc: stable@vger.kernel.org
Fixes: 0fc1b09ff1 ("tracing: Use temp buffer when filtering events")
Reported-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-23 13:59:15 +01:00
Mauro (mdrjr) Ribeiro
de59193db1 Merge tag 'v4.9.238' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.238 stable release

Change-Id: I5aad49a29352f44772f23d33945a369ddfab49bf
2020-12-22 09:19:23 -03:00
Steven Rostedt (VMware)
0bde9d5348 tracing: Fix userstacktrace option for instances
commit bcee527895 upstream.

When the instances were able to use their own options, the userstacktrace
option was left hardcoded for the top level. This made the instance
userstacktrace option bascially into a nop, and will confuse users that set
it, but nothing happens (I was confused when it happened to me!)

Cc: stable@vger.kernel.org
Fixes: 16270145ce ("tracing: Add trace options for core options to instances")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11 13:38:01 +01:00
Qiujun Huang
b134320e5b tracing: Fix out of bounds write in get_trace_buf
commit c1acb4ac1a upstream.

The nesting count of trace_printk allows for 4 levels of nesting. The
nesting counter starts at zero and is incremented before being used to
retrieve the current context's buffer. But the index to the buffer uses the
nesting counter after it was incremented, and not its original number,
which in needs to do.

Link: https://lkml.kernel.org/r/20201029161905.4269-1-hqjagain@gmail.com

Cc: stable@vger.kernel.org
Fixes: 3d9622c12c ("tracing: Add barrier to trace_printk() buffer nesting modification")
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10 10:24:02 +01:00
Nathan Chancellor
efff0333df tracing: Use address-of operator on section symbols
[ Upstream commit bf2cbe044d ]

Clang warns:

../kernel/trace/trace.c:9335:33: warning: array comparison always
evaluates to true [-Wtautological-compare]
        if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt)
                                       ^
1 warning generated.

These are not true arrays, they are linker defined symbols, which are
just addresses. Using the address of operator silences the warning and
does not change the runtime result of the check (tested with some print
statements compiled in with clang + ld.lld and gcc + ld.bfd in QEMU).

Link: http://lkml.kernel.org/r/20200220051011.26113-1-natechancellor@gmail.com

Link: https://github.com/ClangBuiltLinux/linux/issues/893
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 20:40:10 +02:00
Divya Indi
6f46c4f131 tracing: Adding NULL checks for trace_array descriptor pointer
[ Upstream commit 953ae45a0c ]

As part of commit f45d1225ad ("tracing: Kernel access to Ftrace
instances") we exported certain functions. Here, we are adding some additional
NULL checks to ensure safe usage by users of these APIs.

Link: http://lkml.kernel.org/r/1565805327-579-4-git-send-email-divya.indi@oracle.com

Signed-off-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 20:40:03 +02:00
Mauro (mdrjr) Ribeiro
61b0ff0d89 Merge tag 'v4.9.224' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.224 stable release

Change-Id: I0e07ea572bc1a980b42dea56ab1fcb1069640ac1
2020-07-13 17:58:04 -03:00
Steven Rostedt (VMware)
d6e55a35e9 tracing: Add a vmalloc_sync_mappings() for safe measure
commit 11f5efc3ab upstream.

x86_64 lazily maps in the vmalloc pages, and the way this works with per_cpu
areas can be complex, to say the least. Mappings may happen at boot up, and
if nothing synchronizes the page tables, those page mappings may not be
synced till they are used. This causes issues for anything that might touch
one of those mappings in the path of the page fault handler. When one of
those unmapped mappings is touched in the page fault handler, it will cause
another page fault, which in turn will cause a page fault, and leave us in
a loop of page faults.

Commit 763802b53a ("x86/mm: split vmalloc_sync_all()") split
vmalloc_sync_all() into vmalloc_sync_unmappings() and
vmalloc_sync_mappings(), as on system exit, it did not need to do a full
sync on x86_64 (although it still needed to be done on x86_32). By chance,
the vmalloc_sync_all() would synchronize the page mappings done at boot up
and prevent the per cpu area from being a problem for tracing in the page
fault handler. But when that synchronization in the exit of a task became a
nop, it caused the problem to appear.

Link: https://lore.kernel.org/r/20200429054857.66e8e333@oasis.local.home

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>
Suggested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:27 +02:00
Mauro (mdrjr) Ribeiro
f0735e9eb5 Merge tag 'v4.9.199' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.199 stable release
2020-04-07 21:00:55 -03:00
Mauro (mdrjr) Ribeiro
dae544b697 Merge tag 'v4.9.197' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.197 stable release
2020-04-07 21:00:44 -03:00
Mauro (mdrjr) Ribeiro
33417c4f2f Merge tag 'v4.9.187' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.187 stable release
2020-04-07 20:10:04 -03:00
Mauro (mdrjr) Ribeiro
a0510d6c1b Merge tag 'v4.9.185' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.185 stable release
2020-04-07 20:08:40 -03:00
Mauro (mdrjr) Ribeiro
a826960dce Merge tag 'v4.9.181' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.181 stable release
2020-04-07 20:05:31 -03:00
Mauro (mdrjr) Ribeiro
bf2f047532 Merge tag 'v4.9.172' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.172 stable release
2020-04-07 15:05:26 -03:00
Mauro (mdrjr) Ribeiro
572be8936c Merge tag 'v4.9.168' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.168 stable release
2020-04-07 14:57:08 -03:00
Mauro (mdrjr) Ribeiro
fae8d03d01 Merge tag 'v4.9.165' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.165 stable release
2020-04-07 14:56:52 -03:00
Mauro (mdrjr) Ribeiro
22a70830a5 Merge tag 'v4.9.126' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.126 stable release
2020-04-07 13:20:23 -03:00
Mauro (mdrjr) Ribeiro
7e341d6e4a Merge tag 'v4.9.124' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.124 stable release
2020-04-07 11:15:39 -03:00
Mauro (mdrjr) Ribeiro
a6ce694357 Merge tag 'v4.9.119' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into odroidg12-4.9.y
This is the 4.9.119 stable release
2020-04-07 10:35:54 -03:00
Petr Mladek
c24de62408 tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
[ Upstream commit d303de1fcf ]

A customer reported the following softlockup:

[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002]  tracing_read_pipe+0x336/0x3c0
[899688.160002]  __vfs_read+0x26/0x140
[899688.160002]  vfs_read+0x87/0x130
[899688.160002]  SyS_read+0x42/0x90
[899688.160002]  do_syscall_64+0x74/0x160

It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.

Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.

The culprit seems to be in the code:

	/* reset all but tr, trace, and overruns */
	memset(&iter->seq, 0,
	       sizeof(struct trace_iterator) -
	       offsetof(struct trace_iterator, seq));

It was added by the commit 53d0aa7730 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:

     struct trace_seq {
	unsigned char		buffer[PAGE_SIZE];
	unsigned int		len;
     };

There was no "size" variable and zeroing was perfectly fine.

The solution is to reinitialize the structure after or without
zeroing.

Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com

Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 12:18:13 +01:00
Steven Rostedt (VMware)
5e402bab5f tracing: Get trace_array reference for available_tracers files
commit 194c2c74f5 upstream.

As instances may have different tracers available, we need to look at the
trace_array descriptor that shows the list of the available tracers for the
instance. But there's a race between opening the file and an admin
deleting the instance. The trace_array_get() needs to be called before
accessing the trace_array.

Cc: stable@vger.kernel.org
Fixes: 607e2ea167 ("tracing: Set up infrastructure to allow tracers for instances")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-17 13:42:46 -07:00
Eiichi Tsukata
fc19ad387e tracing/snapshot: Resize spare buffer if size changed
commit 46cc0b4442 upstream.

Current snapshot implementation swaps two ring_buffers even though their
sizes are different from each other, that can cause an inconsistency
between the contents of buffer_size_kb file and the current buffer size.

For example:

  # cat buffer_size_kb
  7 (expanded: 1408)
  # echo 1 > events/enable
  # grep bytes per_cpu/cpu0/stats
  bytes: 1441020
  # echo 1 > snapshot             // current:1408, spare:1408
  # echo 123 > buffer_size_kb     // current:123,  spare:1408
  # echo 1 > snapshot             // current:1408, spare:123
  # grep bytes per_cpu/cpu0/stats
  bytes: 1443700
  # cat buffer_size_kb
  123                             // != current:1408

And also, a similar per-cpu case hits the following WARNING:

Reproducer:

  # echo 1 > per_cpu/cpu0/snapshot
  # echo 123 > buffer_size_kb
  # echo 1 > per_cpu/cpu0/snapshot

WARNING:

  WARNING: CPU: 0 PID: 1946 at kernel/trace/trace.c:1607 update_max_tr_single.part.0+0x2b8/0x380
  Modules linked in:
  CPU: 0 PID: 1946 Comm: bash Not tainted 5.2.0-rc6 #20
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014
  RIP: 0010:update_max_tr_single.part.0+0x2b8/0x380
  Code: ff e8 dc da f9 ff 0f 0b e9 88 fe ff ff e8 d0 da f9 ff 44 89 ee bf f5 ff ff ff e8 33 dc f9 ff 41 83 fd f5 74 96 e8 b8 da f9 ff <0f> 0b eb 8d e8 af da f9 ff 0f 0b e9 bf fd ff ff e8 a3 da f9 ff 48
  RSP: 0018:ffff888063e4fca0 EFLAGS: 00010093
  RAX: ffff888066214380 RBX: ffffffff99850fe0 RCX: ffffffff964298a8
  RDX: 0000000000000000 RSI: 00000000fffffff5 RDI: 0000000000000005
  RBP: 1ffff1100c7c9f96 R08: ffff888066214380 R09: ffffed100c7c9f9b
  R10: ffffed100c7c9f9a R11: 0000000000000003 R12: 0000000000000000
  R13: 00000000ffffffea R14: ffff888066214380 R15: ffffffff99851060
  FS:  00007f9f8173c700(0000) GS:ffff88806d000000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000714dc0 CR3: 0000000066fa6000 CR4: 00000000000006f0
  Call Trace:
   ? trace_array_printk_buf+0x140/0x140
   ? __mutex_lock_slowpath+0x10/0x10
   tracing_snapshot_write+0x4c8/0x7f0
   ? trace_printk_init_buffers+0x60/0x60
   ? selinux_file_permission+0x3b/0x540
   ? tracer_preempt_off+0x38/0x506
   ? trace_printk_init_buffers+0x60/0x60
   __vfs_write+0x81/0x100
   vfs_write+0x1e1/0x560
   ksys_write+0x126/0x250
   ? __ia32_sys_read+0xb0/0xb0
   ? do_syscall_64+0x1f/0x390
   do_syscall_64+0xc1/0x390
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

This patch adds resize_buffer_duplicate_size() to check if there is a
difference between current/spare buffer sizes and resize a spare buffer
if necessary.

Link: http://lkml.kernel.org/r/20190625012910.13109-1-devel@etsukata.com

Cc: stable@vger.kernel.org
Fixes: ad909e21bb ("tracing: Add internal tracing_snapshot() functions")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-04 09:33:26 +02:00
Miguel Ojeda
2e41539ee2 tracing: Silence GCC 9 array bounds warning
commit 0c97bf863e upstream.

Starting with GCC 9, -Warray-bounds detects cases when memset is called
starting on a member of a struct but the size to be cleared ends up
writing over further members.

Such a call happens in the trace code to clear, at once, all members
after and including `seq` on struct trace_iterator:

    In function 'memset',
        inlined from 'ftrace_dump' at kernel/trace/trace.c:8914:3:
    ./include/linux/string.h:344:9: warning: '__builtin_memset' offset
    [8505, 8560] from the object at 'iter' is out of the bounds of
    referenced subobject 'seq' with type 'struct trace_seq' at offset
    4368 [-Warray-bounds]
      344 |  return __builtin_memset(p, c, size);
          |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

In order to avoid GCC complaining about it, we compute the address
ourselves by adding the offsetof distance instead of referring
directly to the member.

Since there are two places doing this clear (trace.c and trace_kdb.c),
take the chance to move the workaround into a single place in
the internal header.

Link: http://lkml.kernel.org/r/20190523124535.GA12931@gmail.com

Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
[ Removed unnecessary parenthesis around "iter" ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10 09:55:28 +02:00
Matthew Wilcox
9557090582 fs: prevent page refcount overflow in pipe_buf_get
commit 15fab63e1e upstream.

Change pipe_buf_get() to return a bool indicating whether it succeeded
in raising the refcount of the page (if the thing in the pipe is a page).
This removes another mechanism for overflowing the page refcount.  All
callers converted to handle a failure.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11 12:22:45 +02:00
Wenwen Wang
3ddc299357 tracing: Fix a memory leak by early error exit in trace_pid_write()
commit 91862cc786 upstream.

In trace_pid_write(), the buffer for trace parser is allocated through
kmalloc() in trace_parser_get_init(). Later on, after the buffer is used,
it is then freed through kfree() in trace_parser_put(). However, it is
possible that trace_pid_write() is terminated due to unexpected errors,
e.g., ENOMEM. In that case, the allocated buffer will not be freed, which
is a memory leak bug.

To fix this issue, free the allocated buffer when an error is encountered.

Link: http://lkml.kernel.org/r/1555726979-15633-1-git-send-email-wang6495@umn.edu

Fixes: f4d34a87e9 ("tracing: Use pid bitmap instead of a pid array for set_event_pid")
Cc: stable@vger.kernel.org
Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:32:00 +02:00
Douglas Anderson
3085d41e89 tracing: kdb: Fix ftdump to not sleep
[ Upstream commit 31b265b3ba ]

As reported back in 2016-11 [1], the "ftdump" kdb command triggers a
BUG for "sleeping function called from invalid context".

kdb's "ftdump" command wants to call ring_buffer_read_prepare() in
atomic context.  A very simple solution for this is to add allocation
flags to ring_buffer_read_prepare() so kdb can call it without
triggering the allocation error.  This patch does that.

Note that in the original email thread about this, it was suggested
that perhaps the solution for kdb was to either preallocate the buffer
ahead of time or create our own iterator.  I'm hoping that this
alternative of adding allocation flags to ring_buffer_read_prepare()
can be considered since it means I don't need to duplicate more of the
core trace code into "trace_kdb.c" (for either creating my own
iterator or re-preparing a ring allocator whose memory was already
allocated).

NOTE: another option for kdb is to actually figure out how to make it
reuse the existing ftrace_dump() function and totally eliminate the
duplication.  This sounds very appealing and actually works (the "sr
z" command can be seen to properly dump the ftrace buffer).  The
downside here is that ftrace_dump() fully consumes the trace buffer.
Unless that is changed I'd rather not use it because it means "ftdump
| grep xyz" won't be very useful to search the ftrace buffer since it
will throw away the whole trace on the first grep.  A future patch to
dump only the last few lines of the buffer will also be hard to
implement.

[1] https://lkml.kernel.org/r/20161117191605.GA21459@google.com

Link: http://lkml.kernel.org/r/20190308193205.213659-1-dianders@chromium.org

Reported-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:29:05 +02:00
zhangyi (F)
037a6cf0d5 tracing: Do not free iter->trace in fail path of tracing_open_pipe()
commit e7f0c424d0 upstream.

Commit d716ff71dd ("tracing: Remove taking of trace_types_lock in
pipe files") use the current tracer instead of the copy in
tracing_open_pipe(), but it forget to remove the freeing sentence in
the error path.

There's an error path that can call kfree(iter->trace) after the iter->trace
was assigned to tr->current_trace, which would be bad to free.

Link: http://lkml.kernel.org/r/1550060946-45984-1-git-send-email-yi.zhang@huawei.com

Cc: stable@vger.kernel.org
Fixes: d716ff71dd ("tracing: Remove taking of trace_types_lock in pipe files")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 13:19:45 +01:00
Matthias Kaehlcke
8bd71286fd tracing: Use cpumask_available() to check if cpumask variable may be used
commit 4dbbe2d8e9 upstream.

This fixes the following clang warning:

kernel/trace/trace.c:3231:12: warning: address of array 'iter->started'
  will always evaluate to 'true' [-Wpointer-bool-conversion]
        if (iter->started)

Link: http://lkml.kernel.org/r/20170421234110.117075-1-mka@chromium.org

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-27 10:07:02 +01:00
Steven Rostedt (VMware)
dc69731405 tracing: Do not call start/stop() functions when tracing_on does not change
commit f143641bfe upstream.

Currently, when one echo's in 1 into tracing_on, the current tracer's
"start()" function is executed, even if tracing_on was already one. This can
lead to strange side effects. One being that if the hwlat tracer is enabled,
and someone does "echo 1 > tracing_on" into tracing_on, the hwlat tracer's
start() function is called again which will recreate another kernel thread,
and make it unable to remove the old one.

Link: http://lkml.kernel.org/r/1533120354-22923-1-git-send-email-erica.bugden@linutronix.de

Cc: stable@vger.kernel.org
Fixes: 2df8f8a6a8 ("tracing: Fix regression with irqsoff tracer and tracing_on file")
Reported-by: Erica Bugden <erica.bugden@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09 20:01:22 +02:00
Mathieu Malaterre
bca139fc9b tracing: Use __printf markup to silence compiler
[ Upstream commit 26b68dd2f4 ]

Silence warnings (triggered at W=1) by adding relevant __printf attributes.

  CC      kernel/trace/trace.o
kernel/trace/trace.c: In function ‘__trace_array_vprintk’:
kernel/trace/trace.c:2979:2: warning: function might be possible candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format]
  len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);
  ^~~
  AR      kernel/trace/built-in.o

Link: http://lkml.kernel.org/r/20180308205843.27447-1-malat@debian.org

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:12:35 +02:00
Masami Hiramatsu
a26030a63e ring_buffer: tracing: Inherit the tracing setting to next ring buffer
commit 73c8d89455 upstream.

Maintain the tracing on/off setting of the ring_buffer when switching
to the trace buffer snapshot.

Taking a snapshot is done by swapping the backup ring buffer
(max_tr_buffer). But since the tracing on/off setting is defined
by the ring buffer, when swapping it, the tracing on/off setting
can also be changed. This causes a strange result like below:

  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 0 > tracing_on
  /sys/kernel/debug/tracing # cat tracing_on
  0
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  0

We don't touch tracing_on, but snapshot changes tracing_on
setting each time. This is an anomaly, because user doesn't know
that each "ring_buffer" stores its own tracing-enable state and
the snapshot is done by swapping ring buffers.

Link: http://lkml.kernel.org/r/153149929558.11274.11730609978254724394.stgit@devbox

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Hiraku Toyooka <hiraku.toyooka@cybertrust.co.jp>
Cc: stable@vger.kernel.org
Fixes: debdd57f51 ("tracing: Make a snapshot feature available from userspace")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Updated commit log and comment in the code ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:17:59 +02:00
Matthias Kaehlcke
3341c56cc7 UPSTREAM: tracing: Use cpumask_available() to check if cpumask variable may be used
This fixes the following clang warning:

kernel/trace/trace.c:3231:12: warning: address of array 'iter->started'
  will always evaluate to 'true' [-Wpointer-bool-conversion]
        if (iter->started)

Link: http://lkml.kernel.org/r/20170421234110.117075-1-mka@chromium.org

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
(cherry picked from commit 4dbbe2d8e9)
Bug: 78886293
Change-Id: Ib17a68ce55ca80b04bdea2d232f8ca9f88b1b8a3
Signed-off-by: Alistair Strachan <astrachan@google.com>
2018-05-04 21:13:04 +00:00
Greg Kroah-Hartman
9e5dd8ed9b Merge 4.9.74 into android-4.9
Changes in 4.9.74
	sync objtool's copy of x86-opcode-map.txt
	tracing: Remove extra zeroing out of the ring buffer page
	tracing: Fix possible double free on failure of allocating trace buffer
	tracing: Fix crash when it fails to alloc ring buffer
	ring-buffer: Mask out the info bits when returning buffer page length
	iw_cxgb4: Only validate the MSN for successful completions
	ASoC: wm_adsp: Fix validation of firmware and coeff lengths
	ASoC: da7218: fix fix child-node lookup
	ASoC: fsl_ssi: AC'97 ops need regmap, clock and cleaning up on failure
	ASoC: twl4030: fix child-node lookup
	ASoC: tlv320aic31xx: Fix GPIO1 register definition
	ALSA: hda: Drop useless WARN_ON()
	ALSA: hda - fix headset mic detection issue on a Dell machine
	x86/vm86/32: Switch to flush_tlb_mm_range() in mark_screen_rdonly()
	x86/mm: Remove flush_tlb() and flush_tlb_current_task()
	x86/mm: Make flush_tlb_mm_range() more predictable
	x86/mm: Reimplement flush_tlb_page() using flush_tlb_mm_range()
	x86/mm: Remove the UP asm/tlbflush.h code, always use the (formerly) SMP code
	x86/mm: Disable PCID on 32-bit kernels
	x86/mm: Add the 'nopcid' boot option to turn off PCID
	x86/mm: Enable CR4.PCIDE on supported systems
	x86/mm/64: Fix reboot interaction with CR4.PCIDE
	kbuild: add '-fno-stack-check' to kernel build options
	ipv4: igmp: guard against silly MTU values
	ipv6: mcast: better catch silly mtu values
	net: fec: unmap the xmit buffer that are not transferred by DMA
	net: igmp: Use correct source address on IGMPv3 reports
	netlink: Add netns check on taps
	net: qmi_wwan: add Sierra EM7565 1199:9091
	net: reevalulate autoflowlabel setting after sysctl setting
	ptr_ring: add barriers
	RDS: Check cmsg_len before dereferencing CMSG_DATA
	tcp_bbr: record "full bw reached" decision in new full_bw_reached bit
	tcp md5sig: Use skb's saddr when replying to an incoming segment
	tg3: Fix rx hang on MTU change with 5717/5719
	net: ipv4: fix for a race condition in raw_sendmsg
	net: mvmdio: disable/unprepare clocks in EPROBE_DEFER case
	sctp: Replace use of sockets_allocated with specified macro.
	adding missing rcu_read_unlock in ipxip6_rcv
	ipv4: Fix use-after-free when flushing FIB tables
	net: bridge: fix early call to br_stp_change_bridge_id and plug newlink leaks
	net: fec: Allow reception of frames bigger than 1522 bytes
	net: Fix double free and memory corruption in get_net_ns_by_id()
	net: phy: micrel: ksz9031: reconfigure autoneg after phy autoneg workaround
	sock: free skb in skb_complete_tx_timestamp on error
	tcp: invalidate rate samples during SACK reneging
	net/mlx5: Fix rate limit packet pacing naming and struct
	net/mlx5e: Fix features check of IPv6 traffic
	net/mlx5e: Fix possible deadlock of VXLAN lock
	net/mlx5e: Add refcount to VXLAN structure
	net/mlx5e: Prevent possible races in VXLAN control flow
	net/mlx5: Fix error flow in CREATE_QP command
	s390/qeth: apply takeover changes when mode is toggled
	s390/qeth: don't apply takeover changes to RXIP
	s390/qeth: lock IP table while applying takeover changes
	s390/qeth: update takeover IPs after configuration change
	usbip: fix usbip bind writing random string after command in match_busid
	usbip: prevent leaking socket pointer address in messages
	usbip: stub: stop printing kernel pointer addresses in messages
	usbip: vhci: stop printing kernel pointer addresses in messages
	USB: serial: ftdi_sio: add id for Airbus DS P8GR
	USB: serial: qcserial: add Sierra Wireless EM7565
	USB: serial: option: add support for Telit ME910 PID 0x1101
	USB: serial: option: adding support for YUGA CLM920-NC5
	usb: Add device quirk for Logitech HD Pro Webcam C925e
	usb: add RESET_RESUME for ELSA MicroLink 56K
	USB: Fix off by one in type-specific length check of BOS SSP capability
	usb: xhci: Add XHCI_TRUST_TX_LENGTH for Renesas uPD720201
	timers: Use deferrable base independent of base::nohz_active
	timers: Invoke timer_start_debug() where it makes sense
	timers: Reinitialize per cpu bases on hotplug
	nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()
	x86/smpboot: Remove stale TLB flush invocations
	n_tty: fix EXTPROC vs ICANON interaction with TIOCINQ (aka FIONREAD)
	tty: fix tty_ldisc_receive_buf() documentation
	mm/vmstat: Make NR_TLB_REMOTE_FLUSH_RECEIVED available even on UP
	Linux 4.9.74

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-01-02 20:45:15 +01:00
Jing Xia
81e155e7b0 tracing: Fix crash when it fails to alloc ring buffer
commit 24f2aaf952 upstream.

Double free of the ring buffer happens when it fails to alloc new
ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured.
The root cause is that the pointer is not set to NULL after the buffer
is freed in allocate_trace_buffers(), and the freeing of the ring
buffer is invoked again later if the pointer is not equal to Null,
as:

instance_mkdir()
    |-allocate_trace_buffers()
        |-allocate_trace_buffer(tr, &tr->trace_buffer...)
	|-allocate_trace_buffer(tr, &tr->max_buffer...)

          // allocate fail(-ENOMEM),first free
          // and the buffer pointer is not set to null
        |-ring_buffer_free(tr->trace_buffer.buffer)

       // out_free_tr
    |-free_trace_buffers()
        |-free_trace_buffer(&tr->trace_buffer);

	      //if trace_buffer is not null, free again
	    |-ring_buffer_free(buf->buffer)
                |-rb_free_cpu_buffer(buffer->buffers[cpu])
                    // ring_buffer_per_cpu is null, and
                    // crash in ring_buffer_per_cpu->pages

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Signed-off-by: Jing Xia <jing.xia@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02 20:35:07 +01:00
Steven Rostedt (VMware)
5dc4cd2688 tracing: Fix possible double free on failure of allocating trace buffer
commit 4397f04575 upstream.

Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@spreadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02 20:35:07 +01:00
Steven Rostedt (VMware)
6edea15d12 tracing: Remove extra zeroing out of the ring buffer page
commit 6b7e633fe9 upstream.

The ring_buffer_read_page() takes care of zeroing out any extra data in the
page that it returns. There's no need to zero it out again from the
consumer. It was removed from one consumer of this function, but
read_buffers_splice_read() did not remove it, and worse, it contained a
nasty bug because of it.

Fixes: 2711ca237a ("ring-buffer: Move zeroing out excess in page to ring buffer code")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02 20:35:06 +01:00