From: Yang Yingliang yangyingliang@huawei.com
[ Upstream commit 3b7995a98ad76da5597b488fa84aa5a56d43b608 ]
When I doing fuzzy test, get the memleak report:
BUG: memory leak unreferenced object 0xffff88837af80000 (size 4096): comm "memleak", pid 3557, jiffies 4294817681 (age 112.499s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 20 00 00 00 10 01 00 00 00 00 00 00 01 00 00 00 ............... backtrace: [<000000001c894df8>] bio_alloc_bioset+0x393/0x590 [<000000008b139a3c>] bio_copy_user_iov+0x300/0xcd0 [<00000000a998bd8c>] blk_rq_map_user_iov+0x2f1/0x5f0 [<000000005ceb7f05>] blk_rq_map_user+0xf2/0x160 [<000000006454da92>] sg_common_write.isra.21+0x1094/0x1870 [<00000000064bb208>] sg_write.part.25+0x5d9/0x950 [<000000004fc670f6>] sg_write+0x5f/0x8c [<00000000b0d05c7b>] __vfs_write+0x7c/0x100 [<000000008e177714>] vfs_write+0x1c3/0x500 [<0000000087d23f34>] ksys_write+0xf9/0x200 [<000000002c8dbc9d>] do_syscall_64+0x9f/0x4f0 [<00000000678d8e9a>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
If __blk_rq_map_user_iov() is failed in blk_rq_map_user_iov(), the bio(s) which is allocated before this failing will leak. The refcount of the bio(s) is init to 1 and increased to 2 by calling bio_get(), but __blk_rq_unmap_user() only decrease it to 1, so the bio cannot be freed. Fix it by calling blk_rq_unmap_user().
Reviewed-by: Bob Liu bob.liu@oracle.com Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-map.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/blk-map.c b/block/blk-map.c index e31be14da8ea..f72a3af689b6 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -152,7 +152,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, return 0;
unmap_rq: - __blk_rq_unmap_user(bio); + blk_rq_unmap_user(bio); fail: rq->bio = NULL; return ret;