af_unix: Fix garbage collector racing against connect()
In the Linux kernel, the following vulnerability has been resolved: af_unix: Fix garbage collector racing against connect() Garbage collector does not take into account the risk of embryo getting enqueued during the garbage collection. If such embryo has a peer that carries SCM_RIGHTS, two consecutive passes of scan_children() may see a different set of children. Leading to an incorrectly elevated inflight count, and then a dangling pointer within the gc_inflight_list. sockets are AF_UNIX/SOCK_STREAM S is an unconnected socket L is a listening in-flight socket bound to addr, not in fdtable V's fd will be passed via sendmsg(), gets inflight count bumped connect(S, addr) sendmsg(S, [V]); close(V) __unix_gc() ---------------- ------------------------- ----------- NS = unix_create1() skb1 = sock_wmalloc(NS) L = unix_find_other(addr) unix_state_lock(L) unix_peer(S) = NS // V count=1 inflight=0 NS = unix_peer(S) skb2 = sock_alloc() skb_queue_tail(NS, skb2[V]) // V became in-flight // V count=2 inflight=1 close(V) // V count=1 inflight=1 // GC candidate condition met for u in gc_inflight_list: if (total_refs == inflight_refs) add u to gc_candidates // gc_candidates={L, V} for u in gc_candidates: scan_children(u, dec_inflight) // embryo (skb1) was not // reachable from L yet, so V's // inflight remains unchanged __skb_queue_tail(L, skb1) unix_state_unlock(L) for u in gc_candidates: if (u.inflight) scan_children(u, inc_inflight_move_tail) // V count=1 inflight=2 (!) If there is a GC-c
CVE-2024-26923
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-2024-26923
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": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "a36ae0ec2353015f0f6762e59f4c2dbc0c906423",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "343c5372d5e17b306db5f8f3c895539b06e3177f",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "2e2a03787f4f0abc0072350654ab0ef3324d9db3",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "e76c2678228f6aec74b305ae30c9374cc2f28a51",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "b75722be422c276b699200de90527d01c602ea7c",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "507cc232ffe53a352847893f8177d276c3b532a9",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "dbdf7bec5c920200077d693193f989cb1513f009",
"versionType": "git"
},
{
"status": "affected",
"version": "1fd05ba5a2f2aa8e7b9b52ef55df850e2e7d54c9",
"lessThan": "47d8ac011fe1c9251070e1bd64cb10b48193ec51",
"versionType": "git"
}
],
"programFiles": [
"net/unix/garbage.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.23"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.23",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "4.19.314",
"versionType": "semver",
"lessThanOrEqual": "4.19.*"
},
{
"status": "unaffected",
"version": "5.4.275",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.216",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.156",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.87",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.28",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.8.7",
"versionType": "semver",
"lessThanOrEqual": "6.8.*"
},
{
"status": "unaffected",
"version": "6.9",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/unix/garbage.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2024-26923
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #26459 · Revision 1
- Added to Heist Feed
- Publisher date