| Name | CVE-2021-47591 |
| Description | In the Linux kernel, the following vulnerability has been resolved:
mptcp: remove tcp ulp setsockopt support
TCP_ULP setsockopt cannot be used for mptcp because its already
used internally to plumb subflow (tcp) sockets to the mptcp layer.
syzbot managed to trigger a crash for mptcp connections that are
in fallback mode:
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0
RIP: 0010:tls_build_proto net/tls/tls_main.c:776 [inline]
[..]
__tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline]
tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160
do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391
mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638
Remove support for TCP_ULP setsockopt. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| linux (PTS) | jessie, jessie (lts) | 3.16.84-1 | vulnerable |
| stretch (security) | 4.9.320-2 | vulnerable |
| stretch (lts), stretch | 4.9.320-3 | vulnerable |
| buster (security), buster, buster (lts) | 4.19.316-1 | fixed |
| bullseye | 5.10.223-1 | fixed |
| bullseye (security) | 5.10.226-1 | fixed |
| bookworm | 6.1.115-1 | fixed |
| bookworm (security) | 6.1.112-1 | fixed |
| trixie | 6.11.7-1 | fixed |
| sid | 6.11.9-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| linux | source | jessie | (unfixed) | end-of-life | | |
| linux | source | stretch | (unfixed) | end-of-life | | |
| linux | source | buster | (not affected) | | | |
| linux | source | bullseye | (not affected) | | | |
| linux | source | (unstable) | 5.15.15-1 | | | |
Notes
[bullseye] - linux <not-affected> (Vulnerable code not present)
[buster] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/404cd9a22150f24acf23a8df2ad0c094ba379f57 (5.16-rc6)