linux-stable/kernel/events
kiyin(尹亮) 7bdb157cde perf/core: Fix a memory leak in perf_event_parse_addr_filter()
As shown through runtime testing, the "filename" allocation is not
always freed in perf_event_parse_addr_filter().

There are three possible ways that this could happen:

 - It could be allocated twice on subsequent iterations through the loop,
 - or leaked on the success path,
 - or on the failure path.

Clean up the code flow to make it obvious that 'filename' is always
freed in the reallocation path and in the two return paths as well.

We rely on the fact that kfree(NULL) is NOP and filename is initialized
with NULL.

This fixes the leak. No other side effects expected.

[ Dan Carpenter: cleaned up the code flow & added a changelog. ]
[ Ingo Molnar: updated the changelog some more. ]

Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Signed-off-by: "kiyin(尹亮)" <kiyin@tencent.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: "Srivatsa S. Bhat" <srivatsa@csail.mit.edu>
Cc: Anthony Liguori <aliguori@amazon.com>
--
 kernel/events/core.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)
2020-11-07 13:07:26 +01:00
..
callchain.c uaccess: add force_uaccess_{begin,end} helpers 2020-08-12 10:57:59 -07:00
core.c perf/core: Fix a memory leak in perf_event_parse_addr_filter() 2020-11-07 13:07:26 +01:00
hw_breakpoint.c powerpc/watchpoint: Don't allow concurrent perf and ptrace events 2020-05-19 00:14:45 +10:00
internal.h perf/core: Replace zero-length array with flexible-array 2020-05-19 20:34:16 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ring_buffer.c perf: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
uprobes.c task_work: cleanup notification modes 2020-10-17 15:05:30 -06:00