CVE-2024-56593
Jan. 8, 2025, 4:44 p.m.
5.5
Medium
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.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| Linux |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
CWE-476
NULL Pointer Dereference
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
References
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: LOCAL
- Attack Complexity: LOW
- Privileges Required: LOW
- Scope: UNCHANGED
- Confidentiality Impact: NONE
- Integrity Impact: NONE
- Availability Impact: HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Timeline
Published: Dec. 27, 2024, 3:15 p.m.
Last Modified: Jan. 8, 2025, 4:44 p.m.
Last Modified: Jan. 8, 2025, 4:44 p.m.
Status : Analyzed
CVE has been recently published to the CVE List and has been received by the NVD.
More infoSource
416baaa9-dc9f-4396-8d5f-8c081fb06d67
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.