diff options
| author | xiao jin <jin.xiao@intel.com> | 2018-07-30 14:11:12 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-09 19:55:53 +0200 |
| commit | 0affbaece6d0b7c75c5166732d0481ae9a28be60 (patch) | |
| tree | 5121e4d60c23f75881e803bf82f7a0b9c1276ee6 /block | |
| parent | cf12d0f9c0dc9129f08490390d14ee4d9dbf6ebb (diff) | |
block: blk_init_allocated_queue() set q->fq as NULL in the fail case
commit 54648cf1ec2d7f4b6a71767799c45676a138ca24 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 68bae6338ad4..c9134166dde6 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1025,6 +1025,7 @@ 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); |