Description
In the Linux kernel, the following vulnerability has been resolved: net: tls: prevent chain-after-chain in plain text SG Sashiko points out that if end = 0 (start != 0) the current code will create a chain link to content type right after the wrap link: This would create a chain where the wrap link points directly to another chain link. The scatterlist API sg_next iterator does not recursively resolve consecutive chain links. meaning this is illegal input to crypto. The wrapping link is unnecessary if end = 0. end is the entry after the last one used so end = 0 means there's nothing pushed after the wrap: end start i v v v [ ]...[ ][ d ][ d ][ d ][ d ][rsv for wrap] Skip the wrapping in this case. TLS 1.3 can use the "wrapping slot" for it's chaining if end = 0. This avoids the chain-after-chain. Move the wrap chaining before marking END and chaining off content type, that feels like more logical ordering to me, but should not matter from functional perspective.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/410351158dfef2d67fea6603680b3a6013c6ed9d Patch
- git.kernel.org/stable/c/49a5faaa471ddcd37b6893970c9916eb836e7c31 Patch
- git.kernel.org/stable/c/91359966e247c0244c66d50bbb8e74aefa4321c3 Patch
- git.kernel.org/stable/c/929b1548e63ac72e104c07d8ee8cbbeeba2fa89a Patch
- git.kernel.org/stable/c/acdc12b71c9aa4be5dcd2c8062753c6d2033e235 Patch
- git.kernel.org/stable/c/af855f4c966afafef74faf8390c7b86568c0d46d Patch
- git.kernel.org/stable/c/b9c015ef1a7bf1e8dc67f21c6381f36deb2c3a36 Patch
- git.kernel.org/stable/c/ff26a0e8377dec07e4a7230db7675bed1b9a6d03 Patch
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 44 · as of 14 November 2026
- CWE
- CWE-20
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