CVE-2021-4442
- Source
- https://cve.org/CVERecord?id=CVE-2021-4442
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-4442.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2021-4442
- Downstream
- Related
- Published
- 2024-08-29T11:15:23Z
- Modified
- 2026-03-15T22:42:21Z
- Severity
-
- 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- [none]
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
tcp: add sanity tests to TCP_QUEUE_SEQ
Qingyu Li reported a syzkaller bug where the repro changes RCV SEQ after restoring data in the receive queue.
mprotect(0x4aa000, 12288, PROT_READ) = 0 mmap(0x1ffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x1ffff000 mmap(0x20000000, 16777216, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000 mmap(0x21000000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x21000000 socket(AF_INET6, SOCK_STREAM, IPPROTO_IP) = 3 setsockopt(3, SOL_TCP, TCP_REPAIR, [1], 4) = 0 connect(3, {sa_family=AF_INET6, sin6_port=htons(0), sin6_flowinfo=htonl(0), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_scope_id=0}, 28) = 0 setsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [1], 4) = 0 sendmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="0x0000000000000003\0\0", iov_len=20}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 20 setsockopt(3, SOL_TCP, TCP_REPAIR, [0], 4) = 0 setsockopt(3, SOL_TCP, TCP_QUEUE_SEQ, [128], 4) = 0 recvfrom(3, NULL, 20, 0, NULL, NULL) = -1 ECONNRESET (Connection reset by peer)
syslog shows: [ 111.205099] TCP recvmsg seq # bug 2: copied 80, seq 0, rcvnxt 80, fl 0 [ 111.207894] WARNING: CPU: 1 PID: 356 at net/ipv4/tcp.c:2343 tcp_recvmsg_locked+0x90e/0x29a0
This should not be allowed. TCP_QUEUE_SEQ should only be used when queues are empty.
This patch fixes this case, and the tx path as well.
- References
-
- https://git.kernel.org/stable/c/3b72d5a703842f582502d97906f17d6ee122dac2
- https://git.kernel.org/stable/c/3bf899438c123c444f6b644a57784dfbb6b15ad6
- https://git.kernel.org/stable/c/8811f4a9836e31c14ecdf79d9f3cb7c5d463265d
- https://git.kernel.org/stable/c/046f3c1c2ff450fb7ae53650e9a95e0074a61f3e
- https://git.kernel.org/stable/c/319f460237fc2965a80aa9a055044e1da7b3692a
Affected packages
Git /
Database specific
source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-4442.json"
unresolved_ranges
[
{
"events": [
{
"introduced": "3.5"
},
{
"fixed": "4.19.181"
}
]
},
{
"events": [
{
"introduced": "4.20"
},
{
"fixed": "5.4.106"
}
]
},
{
"events": [
{
"introduced": "5.5"
},
{
"fixed": "5.10.24"
}
]
},
{
"events": [
{
"introduced": "5.11"
},
{
"fixed": "5.11.7"
}
]
},
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.12-rc1"
}
]
},
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.12-rc2"
}
]
}
]