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.
Metrics
Affected Vendors & Products
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4075-1 | linux security update |
Debian DLA |
DLA-4076-1 | linux-6.1 security update |
EUVD |
EUVD-2024-53241 | 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. |
Ubuntu USN |
USN-7379-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7379-2 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7380-1 | Linux kernel (Low Latency) vulnerabilities |
Ubuntu USN |
USN-7381-1 | Linux kernel (Low Latency) vulnerabilities |
Ubuntu USN |
USN-7382-1 | Linux kernel (OEM) vulnerabilities |
Ubuntu USN |
USN-7387-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7387-2 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7387-3 | Linux kernel (Real-time) vulnerabilities |
Ubuntu USN |
USN-7388-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7389-1 | Linux kernel (NVIDIA Tegra) vulnerabilities |
Ubuntu USN |
USN-7390-1 | Linux kernel (Xilinx ZynqMP) vulnerabilities |
Ubuntu USN |
USN-7391-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7392-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7392-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7392-3 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7392-4 | Linux kernel (AWS FIPS) vulnerabilities |
Ubuntu USN |
USN-7393-1 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7401-1 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7407-1 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7413-1 | Linux kernel (IoT) vulnerabilities |
Ubuntu USN |
USN-7421-1 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-7449-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7449-2 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7450-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7451-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7452-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7453-1 | Linux kernel (Real-time) vulnerabilities |
Ubuntu USN |
USN-7458-1 | Linux kernel (IBM) vulnerabilities |
Ubuntu USN |
USN-7459-1 | Linux kernel (Intel IoTG) vulnerabilities |
Ubuntu USN |
USN-7459-2 | Linux kernel (GCP) vulnerabilities |
Ubuntu USN |
USN-7463-1 | Linux kernel (IBM) vulnerabilities |
Ubuntu USN |
USN-7468-1 | Linux kernel (Azure, N-Series) vulnerabilities |
Ubuntu USN |
USN-7523-1 | Linux kernel (Raspberry Pi Real-time) vulnerabilities |
Ubuntu USN |
USN-7524-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7539-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7540-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Mon, 03 Nov 2025 21:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Wed, 01 Oct 2025 20:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Wed, 08 Jan 2025 17:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| Weaknesses | CWE-476 | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
Mon, 30 Dec 2024 01:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Fri, 27 Dec 2024 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | wifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw() | |
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-11-03T20:50:17.021Z
Reserved: 2024-12-27T14:03:06.003Z
Link: CVE-2024-56593
Updated: 2025-11-03T20:50:17.021Z
Status : Modified
Published: 2024-12-27T15:15:18.613
Modified: 2025-11-03T21:18:01.747
Link: CVE-2024-56593
OpenCVE Enrichment
No data.
Debian DLA
EUVD
Ubuntu USN