Description
In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw() This patch fixes a NULL pointer dereference bug in brcmfmac that occurs when a high 'sd_sgentry_align' value applies (e.g. 512) and a lot of queued SKBs are sent from the pkt queue. The problem is the number of entries in the pre-allocated sgtable, it is nents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) >> 4 + 1. Given the default [rt]xglom_size=32 it's actually 35 which is too small. Worst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB is added for each original SKB if tailroom isn't enough to hold tail_pad. At least one sg entry is needed for each SKB. So, eventually the "skb_queue_walk loop" in brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return NULL and this causes the oops. The patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle the worst-case. Btw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464 additional bytes of memory.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
af1fa210f4fc6e304b859b386a3c8a266b1110ab to < 342f87d263462c2670b77ea9a32074cab2ac6fa1affectedaf1fa210f4fc6e304b859b386a3c8a266b1110ab to < 7522d7d745d13fbeff3350fe6aa56c8dae263571affectedaf1fa210f4fc6e304b859b386a3c8a266b1110ab to < dfb3f9d3f602602de208da7bdcc0f6d5ee74af68affectedaf1fa210f4fc6e304b859b386a3c8a266b1110ab to < 67a25ea28f8ec1da8894f2f115d01d3becf67dc7affectedaf1fa210f4fc6e304b859b386a3c8a266b1110ab to < 07c020c6d14d29e5a3ea4e4576b8ecf956a80834affectedaf1fa210f4fc6e304b859b386a3c8a266b1110ab to < 34941321b516bd7c6103bd01287d71a1804d19d3affectedaf1fa210f4fc6e304b859b386a3c8a266b1110ab to < 857282b819cbaa0675aaab1e7542e2c0579f52d7affected
Linux Linux
Default version status: affected
3.15affected0 to < 3.15unaffected5.4.287 to ≤ 5.4.*unaffected5.10.231 to ≤ 5.10.*unaffected5.15.174 to ≤ 5.15.*unaffected6.1.120 to ≤ 6.1.*unaffected6.6.66 to ≤ 6.6.*unaffected6.12.5 to ≤ 6.12.*unaffected6.13 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/342f87d263462c2670b77ea9a32074cab2ac6fa1 ↗
- https://git.kernel.org/stable/c/7522d7d745d13fbeff3350fe6aa56c8dae263571 ↗
- https://git.kernel.org/stable/c/dfb3f9d3f602602de208da7bdcc0f6d5ee74af68 ↗
- https://git.kernel.org/stable/c/67a25ea28f8ec1da8894f2f115d01d3becf67dc7 ↗
- https://git.kernel.org/stable/c/07c020c6d14d29e5a3ea4e4576b8ecf956a80834 ↗
- https://git.kernel.org/stable/c/34941321b516bd7c6103bd01287d71a1804d19d3 ↗
- https://git.kernel.org/stable/c/857282b819cbaa0675aaab1e7542e2c0579f52d7 ↗
- https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html ↗
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html ↗