mirror of https://gitee.com/openkylin/linux.git
1853db0e02
After aligning the ftrace raw samples, there are dead bytes storing
random data from the stack. We don't want to leak these to userspace,
then zero these out.
Before:
0x2de88 [0x50]: event: 9
.
. ... raw event: size 80 bytes
. 0000: 09 00 00 00 01 00 50 00 d0 c7 00 81 ff ff ff ff ......P........
. 0010: 68 01 00 00 68 01 00 00 2c 00 00 00 00 00 00 00 h...h...,......
. 0020: 2c 00 00 00 2b 00 01 02 68 01 00 00 68 01 00 00 ,...+...h...h..
. 0030: 6b 6f 6e 64 65 6d 61 6e 64 2f 30 00 00 00 00 00 kondemand/0....
. 0040: 68 01 00 00 40 7f 46 81 ff ff ff ff 00 10 1b 7f h...@.F........
^ ^ ^ ^
Leak
After:
0x2d318 [0x50]: event: 9
.
. ... raw event: size 80 bytes
. 0000: 09 00 00 00 01 00 50 00 d0 c7 00 81 ff ff ff ff ......P........
. 0010: 68 01 00 00 68 01 00 00 68 14 00 00 00 00 00 00 h...h...h......
. 0020: 2c 00 00 00 2b 00 01 02 68 01 00 00 68 01 00 00 ,...+...h...h..
. 0030: 6b 6f 6e 64 65 6d 61 6e 64 2f 30 00 00 00 00 00 kondemand/0....
. 0040: 68 01 00 00 a0 80 46 81 ff ff ff ff 00 00 00 00 h.....F........
^ ^ ^ ^
Fixed
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1249915116-5210-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
|
||
|---|---|---|
| .. | ||
| events | ||
| boot.h | ||
| define_trace.h | ||
| ftrace.h | ||
| power.h | ||
| syscall.h | ||