diff options
| author | xiao jin <jin.xiao@intel.com> | 2018-07-30 14:11:12 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-11 12:22:18 +0200 |
| commit | c19199167c87841006350cc7c0a59881416e8748 (patch) | |
| tree | 2f8544603311ff7d5bae69d5aee5322895058bc4 /block | |
| parent | 7c4653274b7d254d2d6114e7eb7a5ffe6e5ad0c1 (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>
[groeck: backport to v4.4.y/v4.9.y (context change)]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Alessio Balsini <balsini@android.com>
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 77b99bf16c83..bdb906bbfe19 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -881,6 +881,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, fail: blk_free_flush_queue(q->fq); + q->fq = NULL; return NULL; } EXPORT_SYMBOL(blk_init_allocated_queue); |