diff options
| author | Yu Kuai <[email protected]> | 2023-03-08 10:32:08 +0800 |
|---|---|---|
| committer | Jens Axboe <[email protected]> | 2023-03-08 07:34:50 -0700 |
| commit | e2f2a39452c43b64ea3191642a2661cb8d03827a (patch) | |
| tree | bb85a3d9c05661e2c356f44fa95b0da4e059064d /tools/testing/selftests/bpf/progs/test_prog_array_init.c | |
| parent | e33062213ff2f9151e0d125e1c00f524c2b7acfe (diff) | |
block, bfq: fix uaf for 'stable_merge_bfqq'
Before commit fd571df0ac5b ("block, bfq: turn bfqq_data into an array
in bfq_io_cq"), process reference is read before bfq_put_stable_ref(),
and it's safe if bfq_put_stable_ref() put the last reference, because
process reference will be 0 and 'stable_merge_bfqq' won't be accessed
in this case. However, the commit changed the order and will cause
uaf for 'stable_merge_bfqq'.
In order to emphasize that bfq_put_stable_ref() can drop the last
reference, fix the problem by moving bfq_put_stable_ref() to the end of
bfq_setup_stable_merge().
Fixes: fd571df0ac5b ("block, bfq: turn bfqq_data into an array in bfq_io_cq")
Reported-and-tested-by: Shinichiro Kawasaki <[email protected]>
Link: https://lore.kernel.org/linux-block/20230307071448.rzihxbm4jhbf5krj@shindev/
Signed-off-by: Yu Kuai <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_prog_array_init.c')
0 files changed, 0 insertions, 0 deletions