CVE-2022-50530

In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix null pointer dereference in blk_mq_clear_rq_mapping() Our syzkaller report a null pointer dereference, root cause is following: __blk_mq_alloc_map_and_rqs set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs blk_mq_alloc_map_and_rqs blk_mq_alloc_rqs // failed due to oom alloc_pages_node // set->tags[hctx_idx] is still NULL blk_mq_free_rqs drv_tags = set->tags[hctx_idx]; // null pointer dereference is triggered blk_mq_clear_rq_mapping(drv_tags, ...) This is because commit 63064be150e4 ("blk-mq: Add blk_mq_alloc_map_and_rqs()") merged the two steps: 1) set->tags[hctx_idx] = blk_mq_alloc_rq_map() 2) blk_mq_alloc_rqs(..., set->tags[hctx_idx]) into one step: set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs() Since tags is not initialized yet in this case, fix the problem by checking if tags is NULL pointer in blk_mq_clear_rq_mapping().

The following products are affected by CVE-2022-50530 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2022-50530.

URL	Resource
https://git.kernel.org/stable/c/6a440e6d04431e774dc084abe88c106e2a474c1a
https://git.kernel.org/stable/c/76dd298094f484c6250ebd076fa53287477b2328
https://lore.kernel.org/linux-cve-announce/2025100707-CVE-2022-50530-ef6b@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2022-50530
https://www.cve.org/CVERecord?id=CVE-2022-50530