In the Linux kernel, the following vulnerability has been resolved: soc: fsl: qbman: fix race condition in qman_destroy_fq When QMAN_FQ_FLAG_DYNAMIC_FQID is set, there's a race condition between fq_table[fq->idx] state and freeing/allocating from the pool and WARN_ON(fq_table[fq->idx]) in qman_create_fq() gets triggered. Indeed, we can have: Thread A Thread B qman_destroy_fq() qman_create_fq() qman_release_fqid() qman_shutdown_fq() gen_pool_free() -- At this point, the fqid is available again -- qman_alloc_fqid() -- so, we can get the just-freed fqid in thread B -- fq->fqid = fqid; fq->idx = fqid * 2; WARN_ON(fq_table[fq->idx]); fq_table[fq->idx] = fq; fq_table[fq->idx] = NULL; And adding some logs between qman_release_fqid() and fq_table[fq->idx] = NULL makes the WARN_ON() trigger a lot more. To prevent that, ensure that fq_table[fq->idx] is set to NULL before gen_pool_free() is called by using smp_wmb().
| Vendor | Product | Versions |
|---|---|---|
| linux | linux kernel | c535e923bb97a4b361e89a6383693482057f8b0c, c535e923bb97a4b361e89a6383693482057f8b0c, c535e923bb97a4b361e89a6383693482057f8b0c, c535e923bb97a4b361e89a6383693482057f8b0c, c535e923bb97a4b361e89a6383693482057f8b0c, c535e923bb97a4b361e89a6383693482057f8b0c, 4.9, 7.0-rc4 |
Updated severity to CRITICAL, added affected version 7.0-rc4, and noted that no exploit is available.
Initial creation
