CVE-2024-26923

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Source
https://nvd.nist.gov/vuln/detail/CVE-2024-26923
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-26923.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2024-26923
Aliases
Related
Published
2024-04-25T06:15:57Z
Modified
2024-09-18T03:26:05.715773Z
Summary
[none]
Details

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 SCMRIGHTS, two consecutive passes of scanchildren() may see a different set of children. Leading to an incorrectly elevated inflight count, and then a dangling pointer within the gcinflightlist.

sockets are AFUNIX/SOCKSTREAM 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) _unixgc() ---------------- ------------------------- -----------

NS = unixcreate1() skb1 = sockwmalloc(NS) L = unixfindother(addr) unixstatelock(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

_skbqueuetail(L, skb1) unixstateunlock(L) for u in gccandidates: if (u.inflight) scanchildren(u, incinflightmovetail)

                    // V count=1 inflight=2 (!)

If there is a GC-candidate listening socket, lock/unlock its state. This makes GC wait until the end of any ongoing connect() to that socket. After flipping the lock, a possibly SCM-laden embryo is already enqueued. And if there is another embryo coming, it can not possibly carry SCMRIGHTS. At this point, unixinflight() can not happen because unixgclock is already taken. Inflight graph remains unaffected.

References

Affected packages

Debian:11 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.10.216-1

Affected versions

5.*

5.10.46-4
5.10.46-5
5.10.70-1~bpo10+1
5.10.70-1
5.10.84-1
5.10.92-1~bpo10+1
5.10.92-1
5.10.92-2
5.10.103-1~bpo10+1
5.10.103-1
5.10.106-1
5.10.113-1
5.10.120-1~bpo10+1
5.10.120-1
5.10.127-1
5.10.127-2~bpo10+1
5.10.127-2
5.10.136-1
5.10.140-1
5.10.148-1
5.10.149-1
5.10.149-2
5.10.158-1
5.10.158-2
5.10.162-1
5.10.178-1
5.10.178-2
5.10.178-3
5.10.179-1
5.10.179-2
5.10.179-3
5.10.179-4
5.10.179-5
5.10.191-1
5.10.197-1
5.10.205-1
5.10.205-2
5.10.209-1
5.10.209-2

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
6.1.90-1

Affected versions

6.*

6.1.27-1
6.1.37-1
6.1.38-1
6.1.38-2~bpo11+1
6.1.38-2
6.1.38-3
6.1.38-4~bpo11+1
6.1.38-4
6.1.52-1
6.1.55-1~bpo11+1
6.1.55-1
6.1.64-1
6.1.66-1
6.1.67-1
6.1.69-1~bpo11+1
6.1.69-1
6.1.76-1~bpo11+1
6.1.76-1
6.1.82-1
6.1.85-1
6.1.90-1~bpo11+1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
6.8.9-1

Affected versions

6.*

6.1.27-1
6.1.37-1
6.1.38-1
6.1.38-2~bpo11+1
6.1.38-2
6.1.38-3
6.1.38-4~bpo11+1
6.1.38-4
6.1.52-1
6.1.55-1~bpo11+1
6.1.55-1
6.1.64-1
6.1.66-1
6.1.67-1
6.1.69-1~bpo11+1
6.1.69-1
6.1.76-1~bpo11+1
6.1.76-1
6.1.82-1
6.1.85-1
6.1.90-1~bpo11+1
6.1.90-1
6.1.94-1~bpo11+1
6.1.94-1
6.1.98-1
6.1.99-1
6.1.106-1
6.1.106-2
6.1.106-3
6.3.1-1~exp1
6.3.2-1~exp1
6.3.4-1~exp1
6.3.5-1~exp1
6.3.7-1~bpo12+1
6.3.7-1
6.3.11-1
6.4~rc6-1~exp1
6.4~rc7-1~exp1
6.4.1-1~exp1
6.4.4-1~bpo12+1
6.4.4-1
6.4.4-2
6.4.4-3~bpo12+1
6.4.4-3
6.4.11-1
6.4.13-1
6.5~rc4-1~exp1
6.5~rc6-1~exp1
6.5~rc7-1~exp1
6.5.1-1~exp1
6.5.3-1~bpo12+1
6.5.3-1
6.5.6-1
6.5.8-1
6.5.10-1~bpo12+1
6.5.10-1
6.5.13-1
6.6.3-1~exp1
6.6.4-1~exp1
6.6.7-1~exp1
6.6.8-1
6.6.9-1
6.6.11-1
6.6.13-1~bpo12+1
6.6.13-1
6.6.15-1
6.6.15-2
6.7-1~exp1
6.7.1-1~exp1
6.7.4-1~exp1
6.7.7-1
6.7.9-1
6.7.9-2
6.7.12-1~bpo12+1
6.7.12-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}