bpf: Fix out-of-bounds read of rtt_min in sock_ops
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix out-of-bounds read of rtt_min in sock_ops A sockops prog reading skops->rtt_min never checks the sk type: on the tcp_conn_request() path sock_ops->sk is a request_sock (non-full), and the ctx rewrite casts it to a tcp_sock (full) and reads rtt_min past the end of the request_sock, returning dirty adjacent memory. SEC("sockops") int prog(struct bpf_sock_ops *skops) { switch (skops->op) { case BPF_SOCK_OPS_RWND_INIT: leak = skops->rtt_min; /* reads the request_sock OOB */ ... } } For instance one such read returned rtt_min=0xffff8881, the high half of a leaked kernel pointer. Guarding that cast is exactly what SOCK_OPS_GET_FIELD() does -- it checks is_locked_tcp_sock and returns 0 when sock_ops->sk is not a locked full socket. Every other tcp_sock field in sock_ops goes through it; rtt_min is the only one open-coded, so it skips the check. Read rtt_min through SOCK_OPS_GET_FIELD() too. rtt_min is a bit special: it is a struct minmax and we only want the current min, so pass rtt_min.s[0].v. That is equivalent to the old hand-computed offset offsetof(struct tcp_sock, rtt_min) + sizeof_field(struct minmax_sample, t) (s[0] sits at rtt_min + 0 and .v at + sizeof(.t), i.e. what minmax_get() returns), so the loaded field is unchanged and only the full-sock guard is added. The two BUILD_BUG_ON()s that protected the hand-computed offset are no longer needed. Before patch: 0: r1 = *(u64 *)(r1 +0) ; r1 = skops->s
CVE-2026-98643
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98643
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "0c796efa919f52f788c22c79d1f1b70321696b3d",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "fc9d0e6e9d86fbefe7b8fe6ee49f4cf102add79d",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "fd6bf2721933d8c90bc4ce57f3e204c9295e7e3f",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "a8a9becbac93a9f54f4d565f1f3005eb08a7912f",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "3a46f14e6cf375f3ca38f8f6e6524749e24ea0a8",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "6785313d4fac96afb21ef193610c1fa88b1a9e64",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "cba54d142c43ec96d8c4d566f66439e8c0afded7",
"versionType": "git"
},
{
"status": "affected",
"version": "44f0e43037d3a17b043843ba67610ac7c7e37db6",
"lessThan": "75f8cf22463d82bb1fb0239a3d485fc8f4c8ef03",
"versionType": "git"
}
],
"programFiles": [
"net/core/filter.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.16"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.16",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.271",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.222",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.55",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.9",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/core/filter.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98643
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38663 · Revision 1
- Added to Heist Feed
- Publisher date