In the Linux kernel, the following vulnerability has been resolved: tcp: fix skb_copy_ubufs() vs BIG TCP David Ahern reported crashes in skb_copy_ubufs() caused by TCP tx zerocopy using hugepages, and skb length bigger than ~68 KB. skb_copy_ubufs() assumed it could copy all payload using up to MAX_SKB_FRAGS order-0 pages. This assumption broke when BIG TCP was able to put up to 512 KB per skb. We did not hit this bug at Google because we use CONFIG_MAX_SKB_FRAGS=45 and limit gso_max_size to 180000. A solution is to use higher order pages if needed. v2: add missing __GFP_COMP, or we leak memory.
Fix
Patch, vendor advisory and mitigation references on NVD 4
- https://git.kernel.org/stable/c/3c77a377877acbaf03cd7caa21d3644a5dd16301 Patch
- https://git.kernel.org/stable/c/7e692df3933628d974acb9f5b334d2b3e885e2a6 Patch
- https://git.kernel.org/stable/c/7fa93e39fbb0566019c388a8038a4d58552e0910 Patch
- https://git.kernel.org/stable/c/9cd62f0ba465cf647c7d8c2ca7b0d99ea0c1328f Patch
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 5.5 · linuxNVD modified 2026-10-15 22:17
Affected (CPE criteria) 1
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
References 4
- https://git.kernel.org/stable/c/3c77a377877acbaf03cd7caa21d3644a5dd16301 Patch
- https://git.kernel.org/stable/c/7e692df3933628d974acb9f5b334d2b3e885e2a6 Patch
- https://git.kernel.org/stable/c/7fa93e39fbb0566019c388a8038a4d58552e0910 Patch
- https://git.kernel.org/stable/c/9cd62f0ba465cf647c7d8c2ca7b0d99ea0c1328f Patch