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| author | xiao jin <jin.xiao@intel.com> | 2018-07-30 14:11:12 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-07-30 08:28:39 -0600 |
| commit | 54648cf1ec2d7f4b6a71767799c45676a138ca24 (patch) | |
| tree | 0af9e04a43e25fa1e7206bc30bded1287803c850 /block | |
| parent | f7f1fc363aab4601786d373569c1ae802ea593d0 (diff) | |
| download | linux-54648cf1ec2d7f4b6a71767799c45676a138ca24.tar.gz linux-54648cf1ec2d7f4b6a71767799c45676a138ca24.tar.bz2 linux-54648cf1ec2d7f4b6a71767799c45676a138ca24.zip | |
block: blk_init_allocated_queue() set q->fq as NULL in the fail case
We find the memory use-after-free issue in __blk_drain_queue()
on the kernel 4.14. After read the latest kernel 4.18-rc6 we
think it has the same problem.
Memory is allocated for q->fq in the blk_init_allocated_queue().
If the elevator init function called with error return, it will
run into the fail case to free the q->fq.
Then the __blk_drain_queue() uses the same memory after the free
of the q->fq, it will lead to the unpredictable event.
The patch is to set q->fq as NULL in the fail case of
blk_init_allocated_queue().
Fixes: commit 7c94e1c157a2 ("block: introduce blk_flush_queue to drive flush machinery")
Cc: <stable@vger.kernel.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: xiao jin <jin.xiao@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-core.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 03a4ea93a5f3..23cd1b7770e7 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1184,6 +1184,7 @@ out_exit_flush_rq: q->exit_rq_fn(q, q->fq->flush_rq); out_free_flush_queue: blk_free_flush_queue(q->fq); + q->fq = NULL; return -ENOMEM; } EXPORT_SYMBOL(blk_init_allocated_queue); |