commit 0c97bf863efce63d6ab7971dad811601e6171d2f 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>
commit cbe08bcbbe787315c425dde284dcb715cfbf3f39 upstream.
When reading only part of the id file, the ppos isn't tracked correctly.
This is taken care by simple_read_from_buffer.
Reading a single byte, and then the next byte would result EOF.
While this seems like not a big deal, this breaks abstractions that
reads information from files unbuffered. See for example
https://github.com/golang/go/issues/29399
This code was mentioned as problematic in
commit cd458ba9d5
("tracing: Do not (ab)use trace_seq in event_id_read()")
An example C code that show this bug is:
#include <stdio.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
int main(int argc, char **argv) {
if (argc < 2)
return 1;
int fd = open(argv[1], O_RDONLY);
char c;
read(fd, &c, 1);
printf("First %c\n", c);
read(fd, &c, 1);
printf("Second %c\n", c);
}
Then run with, e.g.
sudo ./a.out /sys/kernel/debug/tracing/events/tcp/tcp_set_state/id
You'll notice you're getting the first character twice, instead of the
first two characters in the id file.
Link: http://lkml.kernel.org/r/20181231115837.4932-1-elazar@lightbitslabs.com
Cc: Orit Wasserman <orit.was@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 23725aeeab ("ftrace: provide an id file for each event")
Signed-off-by: Elazar Leibovich <elazar@lightbitslabs.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d6097c9e4454adf1f8f2c9547c2fa6060d55d952 upstream.
Unless the very next line is schedule(), or implies it, one must not use
preempt_enable_no_resched(). It can cause a preemption to go missing and
thereby cause arbitrary delays, breaking the PREEMPT=y invariant.
Link: http://lkml.kernel.org/r/20190423200318.GY14281@hirez.programming.kicks-ass.net
Cc: Waiman Long <longman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: the arch/x86 maintainers <x86@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: huang ying <huang.ying.caritas@gmail.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: stable@vger.kernel.org
Fixes: 2c2d7329d8 ("tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 31b265b3baaf55f209229888b7ffea523ddab366 ]
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>
commit e7f0c424d0806b05d6f47be9f202b037eb701707 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>
commit 0722069a5374b904ec1a67f91249f90e1cfae259 upstream.
When printing multiple uprobe arguments as strings the output for the
earlier arguments would also include all later string arguments.
This is best explained in an example:
Consider adding a uprobe to a function receiving two strings as
parameters which is at offset 0xa0 in strlib.so and we want to print
both parameters when the uprobe is hit (on x86_64):
$ echo 'p:func /lib/strlib.so:0xa0 +0(%di):string +0(%si):string' > \
/sys/kernel/debug/tracing/uprobe_events
When the function is called as func("foo", "bar") and we hit the probe,
the trace file shows a line like the following:
[...] func: (0x7f7e683706a0) arg1="foobar" arg2="bar"
Note the extra "bar" printed as part of arg1. This behaviour stacks up
for additional string arguments.
The strings are stored in a dynamically growing part of the uprobe
buffer by fetch_store_string() after copying them from userspace via
strncpy_from_user(). The return value of strncpy_from_user() is then
directly used as the required size for the string. However, this does
not take the terminating null byte into account as the documentation
for strncpy_from_user() cleary states that it "[...] returns the
length of the string (not including the trailing NUL)" even though the
null byte will be copied to the destination.
Therefore, subsequent calls to fetch_store_string() will overwrite
the terminating null byte of the most recently fetched string with
the first character of the current string, leading to the
"accumulation" of strings in earlier arguments in the output.
Fix this by incrementing the return value of strncpy_from_user() by
one if we did not hit the maximum buffer size.
Link: http://lkml.kernel.org/r/20190116141629.5752-1-andreas.ziegler@fau.de
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 5baaa59ef0 ("tracing/probes: Implement 'memory' fetch method for uprobes")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2840f84f74035e5a535959d5f17269c69fa6edc5 upstream.
The following commands will cause a memory leak:
# cd /sys/kernel/tracing
# mkdir instances/foo
# echo schedule > instance/foo/set_ftrace_filter
# rmdir instances/foo
The reason is that the hashes that hold the filters to set_ftrace_filter and
set_ftrace_notrace are not freed if they contain any data on the instance
and the instance is removed.
Found by kmemleak detector.
Cc: stable@vger.kernel.org
Fixes: 591dffdade ("ftrace: Allow for function tracing instance to filter functions")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3cec638b3d793b7cacdec5b8072364b41caeb0e1 upstream.
When create_event_filter() fails in set_trigger_filter(), the filter may
still be allocated and needs to be freed. The caller expects the
data->filter to be updated with the new filter, even if the new filter
failed (we could add an error message by setting set_str parameter of
create_event_filter(), but that's another update).
But because the error would just exit, filter was left hanging and
nothing could free it.
Found by kmemleak detector.
Cc: stable@vger.kernel.org
Fixes: bac5fb97a1 ("tracing: Add and use generic set_trigger_filter() implementation")
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1efb6ee3edea57f57f9fb05dba8dcb3f7333f61f ]
A format string consisting of "%p" or "%s" followed by an invalid
specifier (e.g. "%p%\n" or "%s%") could pass the check which
would make format_decode (lib/vsprintf.c) to warn.
Fixes: 9c959c863f ("tracing: Allow BPF programs to call bpf_trace_printk()")
Reported-by: syzbot+1ec5c5ec949c4adaa0c4@syzkaller.appspotmail.com
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit be54f69c26193de31053190761e521903b89d098 ]
# echo 1 > options/stacktrace
# echo 1 > events/sched/sched_switch/enable
# cat trace
<idle>-0 [002] d..2 1982.525169: <stack trace>
=> save_stack_trace
=> __ftrace_trace_stack
=> trace_buffer_unlock_commit_regs
=> event_trigger_unlock_commit
=> trace_event_buffer_commit
=> trace_event_raw_event_sched_switch
=> __schedule
=> schedule
=> schedule_preempt_disabled
=> cpu_startup_entry
=> start_secondary
The above shows that we are seeing 6 functions before ever making it to the
caller of the sched_switch event.
# echo stacktrace > events/sched/sched_switch/trigger
# cat trace
<idle>-0 [002] d..3 2146.335208: <stack trace>
=> trace_event_buffer_commit
=> trace_event_raw_event_sched_switch
=> __schedule
=> schedule
=> schedule_preempt_disabled
=> cpu_startup_entry
=> start_secondary
The stacktrace trigger isn't as bad, because it adds its own skip to the
stacktracing, but still has two events extra.
One issue is that if the stacktrace passes its own "regs" then there should
be no addition to the skip, as the regs will not include the functions being
called. This was an issue that was fixed by commit 7717c6be6999 ("tracing:
Fix stacktrace skip depth in trace_buffer_unlock_commit_regs()" as adding
the skip number for kprobes made the probes not have any stack at all.
But since this is only an issue when regs is being used, a skip should be
added if regs is NULL. Now we have:
# echo 1 > options/stacktrace
# echo 1 > events/sched/sched_switch/enable
# cat trace
<idle>-0 [000] d..2 1297.676333: <stack trace>
=> __schedule
=> schedule
=> schedule_preempt_disabled
=> cpu_startup_entry
=> rest_init
=> start_kernel
=> x86_64_start_reservations
=> x86_64_start_kernel
# echo stacktrace > events/sched/sched_switch/trigger
# cat trace
<idle>-0 [002] d..3 1370.759745: <stack trace>
=> __schedule
=> schedule
=> schedule_preempt_disabled
=> cpu_startup_entry
=> start_secondary
And kprobes are not touched.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 83f365554e47997ec68dc4eca3f5dce525cd15c3 upstream.
When reducing ring buffer size, pages are removed by scheduling a work
item on each CPU for the corresponding CPU ring buffer. After the pages
are removed from ring buffer linked list, the pages are free()d in a
tight loop. The loop does not give up CPU until all pages are removed.
In a worst case behavior, when lot of pages are to be freed, it can
cause system stall.
After the pages are removed from the list, the free() can happen while
the work is rescheduled. Call cond_resched() in the loop to prevent the
system hangup.
Link: http://lkml.kernel.org/r/20180907223129.71994-1-vnagarnaik@google.com
Cc: stable@vger.kernel.org
Fixes: 83f40318da ("ring-buffer: Make removal of ring buffer pages atomic")
Reported-by: Jason Behmer <jbehmer@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 016f8ffc48cb01d1e7701649c728c5d2e737d295 upstream.
While debugging another bug, I was looking at all the synchronize*()
functions being used in kernel/trace, and noticed that trace_uprobes was
using synchronize_sched(), with a comment to synchronize with
{u,ret}_probe_trace_func(). When looking at those functions, the data is
protected with "rcu_read_lock()" and not with "rcu_read_lock_sched()". This
is using the wrong synchronize_*() function.
Link: http://lkml.kernel.org/r/20180809160553.469e1e32@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 70ed91c6ec ("tracing/uprobes: Support ftrace_event_file base multibuffer")
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 757d9140072054528b13bbe291583d9823cde195 upstream.
Masami Hiramatsu reported:
Current trace-enable attribute in sysfs returns an error
if user writes the same setting value as current one,
e.g.
# cat /sys/block/sda/trace/enable
0
# echo 0 > /sys/block/sda/trace/enable
bash: echo: write error: Invalid argument
# echo 1 > /sys/block/sda/trace/enable
# echo 1 > /sys/block/sda/trace/enable
bash: echo: write error: Device or resource busy
But this is not a preferred behavior, it should ignore
if new setting is same as current one. This fixes the
problem as below.
# cat /sys/block/sda/trace/enable
0
# echo 0 > /sys/block/sda/trace/enable
# echo 1 > /sys/block/sda/trace/enable
# echo 1 > /sys/block/sda/trace/enable
Link: http://lkml.kernel.org/r/20180816103802.08678002@gandalf.local.home
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: cd649b8bb8 ("blktrace: remove sysfs_blk_trace_enable_show/store()")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f143641bfef9a4a60c57af30de26c63057e7e695 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>
[ Upstream commit 26b68dd2f48fe7699a89f0cfbb9f4a650dc1c837 ]
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>
commit 73c8d8945505acdcbae137c2e00a1232e0be709f 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>
commit 2519c1bbe38d7acacc9aacba303ca6f97482ed53 upstream.
Commit 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on
enable_trace_kprobe() failure") added an if statement that depends on another
if statement that gcc doesn't see will initialize the "link" variable and
gives the warning:
"warning: 'link' may be used uninitialized in this function"
It is really a false positive, but to quiet the warning, and also to make
sure that it never actually is used uninitialized, initialize the "link"
variable to NULL and add an if (!WARN_ON_ONCE(!link)) where the compiler
thinks it could be used uninitialized.
Cc: stable@vger.kernel.org
Fixes: 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 57ea2a34adf40f3a6e88409aafcf803b8945619a upstream.
If enable_trace_kprobe fails to enable the probe in enable_k(ret)probe
it returns an error, but does not unset the tp flags it set previously.
This results in a probe being considered enabled and failures like being
unable to remove the probe through kprobe_events file since probes_open()
expects every probe to be disabled.
Link: http://lkml.kernel.org/r/20180725102826.8300-1-asavkov@redhat.com
Link: http://lkml.kernel.org/r/20180725142038.4765-1-asavkov@redhat.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 41a7dd420c ("tracing/kprobes: Support ftrace_event_file base multibuffer")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 15cc78644d0075e76d59476a4467e7143860f660 upstream.
There was a case that triggered a double free in event_trigger_callback()
due to the called reg() function freeing the trigger_data and then it
getting freed again by the error return by the caller. The solution there
was to up the trigger_data ref count.
Code inspection found that event_enable_trigger_func() has the same issue,
but is not as easy to trigger (requires harder to trigger failures). It
needs to be solved slightly different as it needs more to clean up when the
reg() function fails.
Link: http://lkml.kernel.org/r/20180725124008.7008e586@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 7862ad1846 ("tracing: Add 'enable_event' and 'disable_event' event trigger commands")
Reivewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1863c387259b629e4ebfb255495f67cd06aa229b upstream.
Running the following:
# cd /sys/kernel/debug/tracing
# echo 500000 > buffer_size_kb
[ Or some other number that takes up most of memory ]
# echo snapshot > events/sched/sched_switch/trigger
Triggers the following bug:
------------[ cut here ]------------
kernel BUG at mm/slub.c:296!
invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
RIP: 0010:kfree+0x16c/0x180
Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f
RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246
RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80
RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500
RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be
R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be
R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00
FS: 00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0
Call Trace:
event_trigger_callback+0xee/0x1d0
event_trigger_write+0xfc/0x1a0
__vfs_write+0x33/0x190
? handle_mm_fault+0x115/0x230
? _cond_resched+0x16/0x40
vfs_write+0xb0/0x190
ksys_write+0x52/0xc0
do_syscall_64+0x5a/0x160
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f363e16ab50
Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24
RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50
RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001
RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700
R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009
R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0
Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper
86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e
---[ end trace d301afa879ddfa25 ]---
The cause is because the register_snapshot_trigger() call failed to
allocate the snapshot buffer, and then called unregister_trigger()
which freed the data that was passed to it. Then on return to the
function that called register_snapshot_trigger(), as it sees it
failed to register, it frees the trigger_data again and causes
a double free.
By calling event_trigger_init() on the trigger_data (which only ups
the reference counter for it), and then event_trigger_free() afterward,
the trigger_data would not get freed by the registering trigger function
as it would only up and lower the ref count for it. If the register
trigger function fails, then the event_trigger_free() called after it
will free the trigger data normally.
Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home
Cc: stable@vger.kerne.org
Fixes: 93e31ffbf4 ("tracing: Add 'snapshot' event trigger command")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 86b389ff22bd6ad8fd3cb98e41cd271886c6d023 upstream.
If a instance has an event trigger enabled when it is freed, it could cause
an access of free memory. Here's the case that crashes:
# cd /sys/kernel/tracing
# mkdir instances/foo
# echo snapshot > instances/foo/events/initcall/initcall_start/trigger
# rmdir instances/foo
Would produce:
general protection fault: 0000 [#1] PREEMPT SMP PTI
Modules linked in: tun bridge ...
CPU: 5 PID: 6203 Comm: rmdir Tainted: G W 4.17.0-rc4-test+ #933
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
RIP: 0010:clear_event_triggers+0x3b/0x70
RSP: 0018:ffffc90003783de0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 6b6b6b6b6b6b6b2b RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800c7130ba0
RBP: ffffc90003783e00 R08: ffff8801131993f8 R09: 0000000100230016
R10: ffffc90003783d80 R11: 0000000000000000 R12: ffff8800c7130ba0
R13: ffff8800c7130bd8 R14: ffff8800cc093768 R15: 00000000ffffff9c
FS: 00007f6f4aa86700(0000) GS:ffff88011eb40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6f4a5aed60 CR3: 00000000cd552001 CR4: 00000000001606e0
Call Trace:
event_trace_del_tracer+0x2a/0xc5
instance_rmdir+0x15c/0x200
tracefs_syscall_rmdir+0x52/0x90
vfs_rmdir+0xdb/0x160
do_rmdir+0x16d/0x1c0
__x64_sys_rmdir+0x17/0x20
do_syscall_64+0x55/0x1a0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
This was due to the call the clears out the triggers when an instance is
being deleted not removing the trigger from the link list.
Cc: stable@vger.kernel.org
Fixes: 85f2b08268 ("tracing: Add basic event trigger framework")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 50268a3d266ecfdd6c5873d62b2758d9732fc598 upstream.
Fix string fetch function to terminate with NUL.
It is OK to drop the rest of string.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org
Cc: 范龙飞 <long7573@126.com>
Fixes: 5baaa59ef0 ("tracing/probes: Implement 'memory' fetch method for uprobes")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dc432c3d7f9bceb3de6f5b44fb9c657c9810ed6d upstream.
The regex match function regex_match_front() in the tracing filter logic,
was fixed to test just the pattern length from testing the entire test
string. That is, it went from strncmp(str, r->pattern, len) to
strcmp(str, r->pattern, r->len).
The issue is that str is not guaranteed to be nul terminated, and if r->len
is greater than the length of str, it can access more memory than is
allocated.
The solution is to add a simple test if (len < r->len) return 0.
Cc: stable@vger.kernel.org
Fixes: 285caad415 ("tracing/filters: Fix MATCH_FRONT_ONLY filter matching")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c5d343b6b7badd1f5fe0873eff2e8d63a193e732 upstream.
In Documentation/trace/kprobetrace.txt, it says
@SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
However, the parser doesn't parse minus offset correctly, since
commit 2fba0c8867 ("tracing/kprobes: Fix probe offset to be
unsigned") drops minus ("-") offset support for kprobe probe
address usage.
This fixes the traceprobe_split_symbol_offset() to parse minus
offset again with checking the offset range, and add a minus
offset check in kprobe probe address usage.
Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 2fba0c8867 ("tracing/kprobes: Fix probe offset to be unsigned")
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7b6586562708d2b3a04fe49f217ddbadbbbb0546 upstream.
__unregister_ftrace_function_probe() will incorrectly parse the glob filter
because it resets the search variable that was setup by filter_parse_regex().
Al Viro reported this:
After that call of filter_parse_regex() we could have func_g.search not
equal to glob only if glob started with '!' or '*'. In the former case
we would've buggered off with -EINVAL (not = 1). In the latter we
would've set func_g.search equal to glob + 1, calculated the length of
that thing in func_g.len and proceeded to reset func_g.search back to
glob.
Suppose the glob is e.g. *foo*. We end up with
func_g.type = MATCH_MIDDLE_ONLY;
func_g.len = 3;
func_g.search = "*foo";
Feeding that to ftrace_match_record() will not do anything sane - we
will be looking for names containing "*foo" (->len is ignored for that
one).
Link: http://lkml.kernel.org/r/20180127031706.GE13338@ZenIV.linux.org.uk
Fixes: 3ba0092971 ("ftrace: Introduce ftrace_glob structure")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1ebe1eaf2f02784921759992ae1fde1a9bec8fd0 upstream.
Since enums do not get converted by the TRACE_EVENT macro into their values,
the event format displaces the enum name and not the value. This breaks
tools like perf and trace-cmd that need to interpret the raw binary data. To
solve this, an enum map was created to convert these enums into their actual
numbers on boot up. This is done by TRACE_EVENTS() adding a
TRACE_DEFINE_ENUM() macro.
Some enums were not being converted. This was caused by an optization that
had a bug in it.
All calls get checked against this enum map to see if it should be converted
or not, and it compares the call's system to the system that the enum map
was created under. If they match, then they call is processed.
To cut down on the number of iterations needed to find the maps with a
matching system, since calls and maps are grouped by system, when a match is
made, the index into the map array is saved, so that the next call, if it
belongs to the same system as the previous call, could start right at that
array index and not have to scan all the previous arrays.
The problem was, the saved index was used as the variable to know if this is
a call in a new system or not. If the index was zero, it was assumed that
the call is in a new system and would keep incrementing the saved index
until it found a matching system. The issue arises when the first matching
system was at index zero. The next map, if it belonged to the same system,
would then think it was the first match and increment the index to one. If
the next call belong to the same system, it would begin its search of the
maps off by one, and miss the first enum that should be converted. This left
a single enum not converted properly.
Also add a comment to describe exactly what that index was for. It took me a
bit too long to figure out what I was thinking when debugging this issue.
Link: http://lkml.kernel.org/r/717BE572-2070-4C1E-9902-9F2E0FEDA4F8@oracle.com
Fixes: 0c564a538a ("tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values")
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Teste-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 45d8b80c2ac5d21cd1e2954431fb676bc2b1e099 upstream.
Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.
What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.
Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 24f2aaf952ee0b59f31c3a18b8b36c9e3d3c2cf5 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>
commit 4397f04575c44e1440ec2e49b6302785c95fd2f8 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>
commit 6b7e633fe9c24682df550e5311f47fb524701586 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>
commit 90e406f96f630c07d631a021fd4af10aac913e77 upstream.
The default NR_CPUS can be very large, but actual possible nr_cpu_ids
usually is very small. For my x86 distribution, the NR_CPUS is 8192 and
nr_cpu_ids is 4. About 2 pages are wasted.
Most machines don't have so many CPUs, so define a array with NR_CPUS
just wastes memory. So let's allocate the buffer dynamically when need.
With this change, the mutext tracing_cpumask_update_lock also can be
removed now, which was used to protect mask_str.
Link: http://lkml.kernel.org/r/1512013183-19107-1-git-send-email-changbin.du@intel.com
Fixes: 36dfe9252b ("ftrace: make use of tracing_cpumask")
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2b0b8499ae75df91455bbeb7491d45affc384fb0 upstream.
The trampoline allocated by function tracer was overwriten by function_graph
tracer, and caused a memory leak. The save_global_trampoline should have
saved the previous trampoline in register_ftrace_graph() and restored it in
unregister_ftrace_graph(). But as it is implemented, save_global_trampoline was
only used in unregister_ftrace_graph as default value 0, and it overwrote the
previous trampoline's value. Causing the previous allocated trampoline to be
lost.
kmmeleak backtrace:
kmemleak_vmalloc+0x77/0xc0
__vmalloc_node_range+0x1b5/0x2c0
module_alloc+0x7c/0xd0
arch_ftrace_update_trampoline+0xb5/0x290
ftrace_startup+0x78/0x210
register_ftrace_function+0x8b/0xd0
function_trace_init+0x4f/0x80
tracing_set_tracer+0xe6/0x170
tracing_set_trace_write+0x90/0xd0
__vfs_write+0x37/0x170
vfs_write+0xb2/0x1b0
SyS_write+0x55/0xc0
do_syscall_64+0x67/0x180
return_from_SYSCALL_64+0x0/0x6a
[
Looking further into this, I found that this was left over from when the
function and function graph tracers shared the same ftrace_ops. But in
commit 5f151b2401 ("ftrace: Fix function_profiler and function tracer
together"), the two were separated, and the save_global_trampoline no
longer was necessary (and it may have been broken back then too).
-- Steven Rostedt
]
Link: http://lkml.kernel.org/r/20170912021454.5976-1-shuwang@redhat.com
Fixes: 5f151b2401 ("ftrace: Fix function_profiler and function tracer together")
Signed-off-by: Shu Wang <shuwang@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8dd33bcb7050dd6f8c1432732f930932c9d3a33e upstream.
One convenient way to erase trace is "echo > trace". However, this
is currently broken if the current tracer is irqsoff tracer. This
is because irqsoff tracer use max_buffer as the default trace
buffer.
Set the max_buffer as the one to be cleared when it's the trace
buffer currently in use.
Link: http://lkml.kernel.org/r/1505754215-29411-1-git-send-email-byan@nvidia.com
Cc: <mingo@redhat.com>
Fixes: 4acd4d00f ("tracing: give easy way to clear trace buffer")
Signed-off-by: Bo Yan <byan@nvidia.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 75df6e688ccd517e339a7c422ef7ad73045b18a2 upstream.
When reading data from trace_pipe, tracing_wait_pipe() performs a
check to see if tracing has been turned off after some data was read.
Currently, this check always looks at global trace state, but it
should be checking the trace instance where trace_pipe is located at.
Because of this bug, cat instances/i1/trace_pipe in the following
script will immediately exit instead of waiting for data:
cd /sys/kernel/debug/tracing
echo 0 > tracing_on
mkdir -p instances/i1
echo 1 > instances/i1/tracing_on
echo 1 > instances/i1/events/sched/sched_process_exec/enable
cat instances/i1/trace_pipe
Link: http://lkml.kernel.org/r/20170917102348.1615-1-tahsin@google.com
Fixes: 10246fa35d ("tracing: give easy way to clear trace buffer")
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit edb096e00724f02db5f6ec7900f3bbd465c6c76f upstream.
If function tracing is disabled by the user via the function-trace option or
the proc sysctl file, and a ftrace_ops that was allocated on the heap is
unregistered, then the shutdown code exits out without doing the proper
clean up. This was found via kmemleak and running the ftrace selftests, as
one of the tests unregisters with function tracing disabled.
# cat kmemleak
unreferenced object 0xffffffffa0020000 (size 4096):
comm "swapper/0", pid 1, jiffies 4294668889 (age 569.209s)
hex dump (first 32 bytes):
55 ff 74 24 10 55 48 89 e5 ff 74 24 18 55 48 89 U.t$.UH...t$.UH.
e5 48 81 ec a8 00 00 00 48 89 44 24 50 48 89 4c .H......H.D$PH.L
backtrace:
[<ffffffff81d64665>] kmemleak_vmalloc+0x85/0xf0
[<ffffffff81355631>] __vmalloc_node_range+0x281/0x3e0
[<ffffffff8109697f>] module_alloc+0x4f/0x90
[<ffffffff81091170>] arch_ftrace_update_trampoline+0x160/0x420
[<ffffffff81249947>] ftrace_startup+0xe7/0x300
[<ffffffff81249bd2>] register_ftrace_function+0x72/0x90
[<ffffffff81263786>] trace_selftest_ops+0x204/0x397
[<ffffffff82bb8971>] trace_selftest_startup_function+0x394/0x624
[<ffffffff81263a75>] run_tracer_selftest+0x15c/0x1d7
[<ffffffff82bb83f1>] init_trace_selftests+0x75/0x192
[<ffffffff81002230>] do_one_initcall+0x90/0x1e2
[<ffffffff82b7d620>] kernel_init_freeable+0x350/0x3fe
[<ffffffff81d61ec3>] kernel_init+0x13/0x122
[<ffffffff81d72c6a>] ret_from_fork+0x2a/0x40
[<ffffffffffffffff>] 0xffffffffffffffff
Fixes: 12cce594fa ("ftrace/x86: Allow !CONFIG_PREEMPT dynamic ops to use allocated trampolines")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 170b3b1050e28d1ba0700e262f0899ffa4fccc52 upstream.
Currently trace_clock timestamps are applied to both regular and max
buffers only for global trace. For instance trace, trace_clock
timestamps are applied only to regular buffer. But, regular and max
buffers can be swapped, for example, following a snapshot. So, for
instance trace, bad timestamps can be seen following a snapshot.
Let's apply trace_clock timestamps to instance max buffer as well.
Link: http://lkml.kernel.org/r/ebdb168d0be042dcdf51f81e696b17fabe3609c1.1504642143.git.tom.zanussi@linux.intel.com
Fixes: 277ba0446 ("tracing: Add interface to allow multiple trace buffers")
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 46320a6acc4fb58f04bcf78c4c942cc43b20f986 upstream.
In the second iteration of trace_selftest_ops(), the error goto label is
wrong in the case where trace_selftest_test_global_cnt is off. In the
case of error, it leaks the dynamic ops that was allocated.
Fixes: 95950c2e ("ftrace: Add self-tests for multiple function trace users")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8b0db1a5bdfcee0dbfa89607672598ae203c9045 upstream.
Performing the following task with kmemleak enabled:
# cd /sys/kernel/tracing/events/irq/irq_handler_entry/
# echo 'enable_event:kmem:kmalloc:3 if irq >' > trigger
# echo 'enable_event:kmem:kmalloc:3 if irq > 31' > trigger
# echo scan > /sys/kernel/debug/kmemleak
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff8800b9290308 (size 32):
comm "bash", pid 1114, jiffies 4294848451 (age 141.139s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff81cef5aa>] kmemleak_alloc+0x4a/0xa0
[<ffffffff81357938>] kmem_cache_alloc_trace+0x158/0x290
[<ffffffff81261c09>] create_filter_start.constprop.28+0x99/0x940
[<ffffffff812639c9>] create_filter+0xa9/0x160
[<ffffffff81263bdc>] create_event_filter+0xc/0x10
[<ffffffff812655e5>] set_trigger_filter+0xe5/0x210
[<ffffffff812660c4>] event_enable_trigger_func+0x324/0x490
[<ffffffff812652e2>] event_trigger_write+0x1a2/0x260
[<ffffffff8138cf87>] __vfs_write+0xd7/0x380
[<ffffffff8138f421>] vfs_write+0x101/0x260
[<ffffffff8139187b>] SyS_write+0xab/0x130
[<ffffffff81cfd501>] entry_SYSCALL_64_fastpath+0x1f/0xbe
[<ffffffffffffffff>] 0xffffffffffffffff
The function create_filter() is passed a 'filterp' pointer that gets
allocated, and if "set_str" is true, it is up to the caller to free it, even
on error. The problem is that the pointer is not freed by create_filter()
when set_str is false. This is a bug, and it is not up to the caller to free
the filter on error if it doesn't care about the string.
Link: http://lkml.kernel.org/r/1502705898-27571-2-git-send-email-chuhu@redhat.com
Fixes: 38b78eb85 ("tracing: Factorize filter creation")
Reported-by: Chunyu Hu <chuhu@redhat.com>
Tested-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit db9108e054700c96322b0f0028546aa4e643cf0b upstream.
Hit the kmemleak when executing instance_rmdir, it forgot releasing
mem of tracing_cpumask. With this fix, the warn does not appear any
more.
unreferenced object 0xffff93a8dfaa7c18 (size 8):
comm "mkdir", pid 1436, jiffies 4294763622 (age 9134.308s)
hex dump (first 8 bytes):
ff ff ff ff ff ff ff ff ........
backtrace:
[<ffffffff88b6567a>] kmemleak_alloc+0x4a/0xa0
[<ffffffff8861ea41>] __kmalloc_node+0xf1/0x280
[<ffffffff88b505d3>] alloc_cpumask_var_node+0x23/0x30
[<ffffffff88b5060e>] alloc_cpumask_var+0xe/0x10
[<ffffffff88571ab0>] instance_mkdir+0x90/0x240
[<ffffffff886e5100>] tracefs_syscall_mkdir+0x40/0x70
[<ffffffff886565c9>] vfs_mkdir+0x109/0x1b0
[<ffffffff8865b1d0>] SyS_mkdir+0xd0/0x100
[<ffffffff88403857>] do_syscall_64+0x67/0x150
[<ffffffff88b710e7>] return_from_SYSCALL_64+0x0/0x6a
[<ffffffffffffffff>] 0xffffffffffffffff
Link: http://lkml.kernel.org/r/1500546969-12594-1-git-send-email-chuhu@redhat.com
Fixes: ccfe9e42e4 ("tracing: Make tracing_cpumask available for all instances")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2e028c4fe12907f226b8221815f16c2486ad3aa7 upstream.
My static checker complains that if "func" is NULL then "clear_filter"
is uninitialized. This seems like it could be true, although it's
possible something subtle is happening that I haven't seen.
kernel/trace/ftrace.c:3844 match_records()
error: uninitialized symbol 'clear_filter'.
Link: http://lkml.kernel.org/r/20170712073556.h6tkpjcdzjaozozs@mwanda
Fixes: f0a3b154bd ("ftrace: Clarify code for mod command")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c59f29cb144a6a0dfac16ede9dc8eafc02dc56ca upstream.
The 's' flag is supposed to indicate that a softirq is running. This
can be detected by testing the preempt_count with SOFTIRQ_OFFSET.
The current code tests the preempt_count with SOFTIRQ_MASK, which
would be true even when softirqs are disabled but not serving a
softirq.
Link: http://lkml.kernel.org/r/1481300417-3564-1-git-send-email-pkondeti@codeaurora.org
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9e52b32567126fe146f198971364f68d3bc5233f upstream.
Always try to parse an address, since kstrtoul() will safely fail when
given a symbol as input. If that fails (which will be the case for a
symbol), try to parse a symbol instead.
This allows creating a probe such as:
p:probe/vlan_gro_receive 8021q:vlan_gro_receive+0
Which is necessary for this command to work:
perf probe -m 8021q -a vlan_gro_receive
Link: http://lkml.kernel.org/r/fd72d666f45b114e2c5b9cf7e27b91de1ec966f1.1498122881.git.sd@queasysnail.net
Fixes: 413d37d1e ("tracing: Add kprobe-based event tracer")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 30e7d894c1478c88d50ce94ddcdbd7f9763d9cdd upstream.
Enabling the tracer selftest triggers occasionally the warning in
text_poke(), which warns when the to be modified page is not marked
reserved.
The reason is that the tracer selftest installs kprobes on functions marked
__init for testing. These probes are removed after the tests, but that
removal schedules the delayed kprobes_optimizer work, which will do the
actual text poke. If the work is executed after the init text is freed,
then the warning triggers. The bug can be reproduced reliably when the work
delay is increased.
Flush the optimizer work and wait for the optimizing/unoptimizing lists to
become empty before returning from the kprobes tracer selftest. That
ensures that all operations which were queued due to the probes removal
have completed.
Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.home
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 6274de498 ("kprobes: Support delayed unoptimizing")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 78f7a45dac2a2d2002f98a3a95f7979867868d73 upstream.
I noticed that reading the snapshot file when it is empty no longer gives a
status. It suppose to show the status of the snapshot buffer as well as how
to allocate and use it. For example:
># cat snapshot
# tracer: nop
#
#
# * Snapshot is allocated *
#
# Snapshot commands:
# echo 0 > snapshot : Clears and frees snapshot buffer
# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.
# Takes a snapshot of the main buffer.
# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)
# (Doesn't have to be '2' works with any number that
# is not a '0' or '1')
But instead it just showed an empty buffer:
># cat snapshot
# tracer: nop
#
# entries-in-buffer/entries-written: 0/0 #P:4
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
What happened was that it was using the ring_buffer_iter_empty() function to
see if it was empty, and if it was, it showed the status. But that function
was returning false when it was empty. The reason was that the iter header
page was on the reader page, and the reader page was empty, but so was the
buffer itself. The check only tested to see if the iter was on the commit
page, but the commit page was no longer pointing to the reader page, but as
all pages were empty, the buffer is also.
Fixes: 651e22f270 ("ring-buffer: Always reset iterator to reader page")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit df62db5be2e5f070ecd1a5ece5945b590ee112e0 upstream.
Currently the snapshot trigger enables the probe and then allocates the
snapshot. If the probe triggers before the allocation, it could cause the
snapshot to fail and turn tracing off. It's best to allocate the snapshot
buffer first, and then enable the trigger. If something goes wrong in the
enabling of the trigger, the snapshot buffer is still allocated, but it can
also be freed by the user by writting zero into the snapshot buffer file.
Also add a check of the return status of alloc_snapshot().
Fixes: 77fd5c15e3 ("tracing: Add snapshot trigger to function probes")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
