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author | Peter Zijlstra <peterz@infradead.org> | 2015-12-15 13:49:05 +0100 |
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committer | Ben Hutchings <ben@decadent.org.uk> | 2017-02-23 03:54:44 +0000 |
commit | 311c3b32f1e591b88e1b290efdcbc79c081f8e0f (patch) | |
tree | f28f766e94e9b675deda0cff952069e1cc9c1373 /drivers/tty | |
parent | 79cfd63480a7c4b48c6c329fab1bde569e0a4ac2 (diff) | |
download | linux-stable-311c3b32f1e591b88e1b290efdcbc79c081f8e0f.tar.gz linux-stable-311c3b32f1e591b88e1b290efdcbc79c081f8e0f.tar.bz2 linux-stable-311c3b32f1e591b88e1b290efdcbc79c081f8e0f.zip |
perf: Fix race in swevent hash
commit 12ca6ad2e3a896256f086497a7c7406a547ee373 upstream.
There's a race on CPU unplug where we free the swevent hash array
while it can still have events on. This will result in a
use-after-free which is BAD.
Simply do not free the hash array on unplug. This leaves the thing
around and no use-after-free takes place.
When the last swevent dies, we do a for_each_possible_cpu() iteration
anyway to clean these up, at which time we'll free it, so no leakage
will occur.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/tty')
0 files changed, 0 insertions, 0 deletions