tree b1da62f490b2caa1bca6e8b5755a5d143d258c4e
parent 58bfceb0275f8ada9e8816c12902f63e524d1243
author Adrian Salido <salidoa@google.com> 1492541073 -0700
committer Todd Kjos <tkjos@google.com> 1541201181 -0700

ANDROID: tracing: fix race condition reading saved tgids

Commit 939c7a4f04fc ("tracing: Introduce saved_cmdlines_size file")
introduced ability to change saved cmdlines size. This resized saved
command lines but missed resizing tgid mapping as well.

Another issue is that when the resize happens, it removes saved command
lines and reallocates new memory for it. This introduced a race
condition when reading the global savecmd as this can be freed in the
middle of accessing it causing a use after free access. Fix this by
implementing locking.

Signed-off-by: Adrian Salido <salidoa@google.com>
Bug: 36007735
Change-Id: I334791ac35f8bcbd34362ed112aa624275a46947
(cherry picked from commit 7116d306da66de0de21e982024b4d3a3056f4461)