Description
In the Linux kernel, the following vulnerability has been resolved: nvmet: fix race in nvmet_bio_done() leading to NULL pointer dereference There is a race condition in nvmet_bio_done() that can cause a NULL pointer dereference in blk_cgroup_bio_start(): 1. nvmet_bio_done() is called when a bio completes 2. nvmet_req_complete() is called, which invokes req->ops->queue_response(req) 3. The queue_response callback can re-queue and re-submit the same request 4. The re-submission reuses the same inline_bio from nvmet_req 5. Meanwhile, nvmet_req_bio_put() (called after nvmet_req_complete) invokes bio_uninit() for inline_bio, which sets bio->bi_blkg to NULL 6. The re-submitted bio enters submit_bio_noacct_nocheck() 7. blk_cgroup_bio_start() dereferences bio->bi_blkg, causing a crash: BUG: kernel NULL pointer dereference, address: 0000000000000028 #PF: supervisor read access in kernel mode RIP: 0010:blk_cgroup_bio_start+0x10/0xd0 Call Trace: submit_bio_noacct_nocheck+0x44/0x250 nvmet_bdev_execute_rw+0x254/0x370 [nvmet] process_one_work+0x193/0x3c0 worker_thread+0x281/0x3a0 Fix this by reordering nvmet_bio_done() to call nvmet_req_bio_put() BEFORE nvmet_req_complete(). This ensures the bio is cleaned up before the request can be re-submitted, preventing the race condition.
Product status
431e58d56fcb5ff1f9eb630724a922e0d2a941df (git) before ee10b06980acca1d46e0fa36d6fb4a9578eab6e4
190f4c2c863af7cc5bb354b70e0805f06419c038 (git) before 68207ceefd71cc74ce4e983fa9bd10c3122e349b
190f4c2c863af7cc5bb354b70e0805f06419c038 (git) before 0fcee2cfc4b2e16e62ff8e0cc2cd8dd24efad65e
2e2028fcf924d1c6df017033c8d6e28b735a0508 (git)
6.16
Any version before 6.16
6.12.69 (semver)
6.18.9 (semver)
6.19 (original_commit_for_fix)
References
git.kernel.org/...c/ee10b06980acca1d46e0fa36d6fb4a9578eab6e4
git.kernel.org/...c/68207ceefd71cc74ce4e983fa9bd10c3122e349b
git.kernel.org/...c/0fcee2cfc4b2e16e62ff8e0cc2cd8dd24efad65e