bpf, sockmap: Fix race between element replace and close()
In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Fix race between element replace and close() Element replace (with a socket different from the one stored) may race with socket's close() link popping & unlinking. __sock_map_delete() unconditionally unrefs the (wrong) element: // set map[0] = s0 map_update_elem(map, 0, s0) // drop fd of s0 close(s0) sock_map_close() lock_sock(sk) (s0!) sock_map_remove_links(sk) link = sk_psock_link_pop() sock_map_unlink(sk, link) sock_map_delete_from_link // replace map[0] with s1 map_update_elem(map, 0, s1) sock_map_update_elem (s1!) lock_sock(sk) sock_map_update_common psock = sk_psock(sk) spin_lock(&stab->lock) osk = stab->sks[idx] sock_map_add_link(..., &stab->sks[idx]) sock_map_unref(osk, &stab->sks[idx]) psock = sk_psock(osk) sk_psock_put(sk, psock) if (refcount_dec_and_test(&psock)) sk_psock_drop(sk, psock) spin_unlock(&stab->lock) unlock_sock(sk) __sock_map_delete spin_lock(&stab->lock) sk = *psk // s1 replaced s0; sk == s1 if (!sk_test || sk_test == sk) // sk_test (s0) != sk (s1); no branch sk = xchg(psk, NULL) if (sk) sock_map_unref(sk, psk) // unref s1; sks[idx] will dangle psock = sk_psock(sk) sk_psock_put(sk, psock) if (refcount_dec_and_test()) sk_psock_drop(sk, psock) spin_unlock(&stab->lock) release_sock(sk) Then close(map) enqueues bpf_map_free_deferred, which finally calls sock_map_free(). This results in some refcount_t warnings along with a KASAN splat [1]. Fix __sock_map_delete(), do not all
CVE-2024-56664
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-2024-56664
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": "604326b41a6fb9b4a78b6179335decee0365cd8c",
"lessThan": "6deb9e85dc9a2ba4414b91c1b5b00b8415910890",
"versionType": "git"
},
{
"status": "affected",
"version": "604326b41a6fb9b4a78b6179335decee0365cd8c",
"lessThan": "fdb2cd8957ac51f84c9e742ba866087944bb834b",
"versionType": "git"
},
{
"status": "affected",
"version": "604326b41a6fb9b4a78b6179335decee0365cd8c",
"lessThan": "b79a0d1e9a374d1b376933a354c4fcd01fce0365",
"versionType": "git"
},
{
"status": "affected",
"version": "604326b41a6fb9b4a78b6179335decee0365cd8c",
"lessThan": "b015f19fedd2e12283a8450dd0aefce49ec57015",
"versionType": "git"
},
{
"status": "affected",
"version": "604326b41a6fb9b4a78b6179335decee0365cd8c",
"lessThan": "bf2318e288f636a882eea39f7e1015623629f168",
"versionType": "git"
},
{
"status": "affected",
"version": "604326b41a6fb9b4a78b6179335decee0365cd8c",
"lessThan": "ed1fc5d76b81a4d681211333c026202cad4d5649",
"versionType": "git"
}
],
"programFiles": [
"net/core/sock_map.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.20"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.20",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.236",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.180",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.125",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.67",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.6",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.13",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/core/sock_map.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2024-56664
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #30399 · Revision 1
- Added to Heist Feed
- Publisher date