linux-stable.git/kernel/trace, branch linux-4.8.y

fgraph: Handle a case where a tracer ignores set_graph_notrace

2017-01-09T07:21:58+00:00

commit 794de08a16cf1fc1bf785dc48f66d36218cf6d88 upstream.

Both the wakeup and irqsoff tracers can use the function graph tracer when
the display-graph option is set. The problem is that they ignore the notrace
file, and record the entry of functions that would be ignored by the
function_graph tracer. This causes the trace->depth to be recorded into the
ring buffer. The set_graph_notrace uses a trick by adding a large negative
number to the trace->depth when a graph function is to be ignored.

On trace output, the graph function uses the depth to record a stack of
functions. But since the depth is negative, it accesses the array with a
negative number and causes an out of bounds access that can cause a kernel
oops or corrupt data.

Have the print functions handle cases where a tracer still records functions
even when they are in set_graph_notrace.

Also add warnings if the depth is below zero before accessing the array.

Note, the function graph logic will still prevent the return of these
functions from being recorded, which means that they will be left hanging
without a return. For example:

   # echo '*spin*' > set_graph_notrace
   # echo 1 > options/display-graph
   # echo wakeup > current_tracer
   # cat trace
   [...]
      _raw_spin_lock() {
        preempt_count_add() {
        do_raw_spin_lock() {
      update_rq_clock();

Where it should look like:

      _raw_spin_lock() {
        preempt_count_add();
        do_raw_spin_lock();
      }
      update_rq_clock();

Cc: Namhyung Kim 
Fixes: 29ad23b00474 ("ftrace: Add set_graph_notrace filter")
Signed-off-by: Steven Rostedt 
Signed-off-by: Greg Kroah-Hartman

Disable the __builtin_return_address() warning globally after all

2016-11-26T08:56:55+00:00

commit ef6000b4c6706cbb1787836442b5a74542b1809f upstream.

This affectively reverts commit 377ccbb48373 ("Makefile: Mute warning
for __builtin_return_address(>0) for tracing only") because it turns out
that it really isn't tracing only - it's all over the tree.

We already also had the warning disabled separately for mm/usercopy.c
(which this commit also removes), and it turns out that we will also
want to disable it for get_lock_parent_ip(), that is used for at least
TRACE_IRQFLAGS.  Which (when enabled) ends up being all over the tree.

Steven Rostedt had a patch that tried to limit it to just the config
options that actually triggered this, but quite frankly, the extra
complexity and abstraction just isn't worth it.  We have never actually
had a case where the warning is actually useful, so let's just disable
it globally and not worry about it.

Acked-by: Steven Rostedt 
Cc: Thomas Gleixner 
Cc: Andrew Morton 
Cc: Ingo Molnar 
Cc: Peter Anvin 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ftrace: Add more checks for FTRACE_FL_DISABLED in processing ip records

2016-11-26T08:56:53+00:00

commit 546fece4eae871f033925ccf0ff2b740725ae915 upstream.

When a module is first loaded and its function ip records are added to the
ftrace list of functions to modify, they are set to DISABLED, as their text
is still in a read only state. When the module is fully loaded, and can be
updated, the flag is cleared, and if their's any functions that should be
tracing them, it is updated at that moment.

But there's several locations that do record accounting and should ignore
records that are marked as disabled, or they can cause issues.

Alexei already fixed one location, but others need to be addressed.

Fixes: b7ffffbb46f2 "ftrace: Add infrastructure for delayed enabling of module functions"
Reported-by: Alexei Starovoitov 
Signed-off-by: Steven Rostedt 
Signed-off-by: Greg Kroah-Hartman

ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records

2016-11-26T08:56:53+00:00

commit 977c1f9c8c022d0173181766b34a0db3705265a4 upstream.

ftrace_shutdown() checks for sanity of ftrace records
and if dyn_ftrace->flags is not zero, it will warn.
It can happen that 'flags' are set to FTRACE_FL_DISABLED at this point,
since some module was loaded, but before ftrace_module_enable()
cleared the flags for this module.

In other words the module.c is doing:
ftrace_module_init(mod); // calls ftrace_update_code() that sets flags=FTRACE_FL_DISABLED
... // here ftrace_shutdown() is called that warns, since
err = prepare_coming_module(mod); // didn't have a chance to clear FTRACE_FL_DISABLED

Fix it by ignoring disabled records.
It's similar to what __ftrace_hash_rec_update() is already doing.

Link: http://lkml.kernel.org/r/1478560460-3818619-1-git-send-email-ast@fb.com

Fixes: b7ffffbb46f2 "ftrace: Add infrastructure for delayed enabling of module functions"
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Steven Rostedt 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'trace-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2016-09-26T01:40:13+00:00

Pull tracefs fixes from Steven Rostedt:
 "Al Viro has been looking at the tracefs code, and has pointed out some
  issues.  This contains one fix by me and one by Al.  I'm sure that
  he'll come up with more but for now I tested these patches and they
  don't appear to have any negative impact on tracing"

* tag 'trace-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  fix memory leaks in tracing_buffers_splice_read()
  tracing: Move mutex to protect against resetting of seq data

fix memory leaks in tracing_buffers_splice_read()

2016-09-25T17:30:13+00:00

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro

tracing: Move mutex to protect against resetting of seq data

2016-09-25T14:27:08+00:00

The iter->seq can be reset outside the protection of the mutex. So can
reading of user data. Move the mutex up to the beginning of the function.

Fixes: d7350c3f45694 ("tracing/core: make the read callbacks reentrants")
Cc: stable@vger.kernel.org # 2.6.30+
Reported-by: Al Viro 
Signed-off-by: Steven Rostedt

block: Fix secure erase

2016-08-16T15:16:51+00:00

Commit 288dab8a35a0 ("block: add a separate operation type for secure
erase") split REQ_OP_SECURE_ERASE from REQ_OP_DISCARD without considering
all the places REQ_OP_DISCARD was being used to mean either. Fix those.

Signed-off-by: Adrian Hunter 
Fixes: 288dab8a35a0 ("block: add a separate operation type for secure erase")
Signed-off-by: Jens Axboe

block: rename bio bi_rw to bi_opf

2016-08-07T20:41:02+00:00

Since commit 63a4cc24867d, bio->bi_rw contains flags in the lower
portion and the op code in the higher portions. This means that
old code that relies on manually setting bi_rw is most likely
going to be broken. Instead of letting that brokeness linger,
rename the member, to force old and out-of-tree code to break
at compile time instead of at runtime.

No intended functional changes in this commit.

Signed-off-by: Jens Axboe

Merge tag 'trace-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2016-08-03T16:50:06+00:00

Pull tracing fixes from Steven Rostedt:
 "A few updates and fixes:

   - move the suppressing of the __builtin_return_address >0 warning to
     the tracing directory only.

   - metag recordmcount fix for newer glibc's

   - two tracing histogram fixes that were reported by KASAN"

* tag 'trace-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix use-after-free in hist_register_trigger()
  tracing: Fix use-after-free in hist_unreg_all/hist_enable_unreg_all
  Makefile: Mute warning for __builtin_return_address(>0) for tracing only
  ftrace/recordmcount: Work around for addition of metag magic but not relocations