UBUNTU-CVE-2021-4442
Vulnerability Summary
Timeline
Description
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.
CVSS Metrics
- v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected Systems
- ubuntu•linux
all | < 4.15.0-144.148 | < 5.4.0-73.82
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
all | < 4.15.0-1103.110 | < 5.4.0-1048.50
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.4
< 5.4.0-1048.50~18.04.1
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-fips
< 4.15.0-2045.47 | all | < 5.4.0-1069.73+fips2
- ubuntu•linux-aws-hwe
< 4.15.0-1103.110~16.04.1
- ubuntu•linux-azure
< 4.15.0-1115.128~14.04.1 | < 4.15.0-1115.128~16.04.1 | all | < 5.4.0-1047.49
- ubuntu•linux-azure-4.15
< 4.15.0-1115.128
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.4
< 5.4.0-1047.49~18.04.1
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fips
< 4.15.0-2027.30 | all | < 5.4.0-1073.76+fips1
- ubuntu•linux-bluefield
all
- ubuntu•linux-fips
all | < 4.15.0-1060.68
- ubuntu•linux-gcp
< 4.15.0-1100.113~16.04.1 | all | < 5.4.0-1043.46
- ubuntu•linux-gcp-4.15
< 4.15.0-1100.113
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.19
all
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.4
< 5.4.0-1043.46~18.04.1
- ubuntu•linux-gcp-5.8
all
- ubuntu•linux-gcp-6.2
all
- ubuntu•linux-gcp-6.5
all
- ubuntu•linux-gcp-fips
all | < 5.4.0-1067.71~20.04.1
- ubuntu•linux-gke
all
- ubuntu•linux-gke-4.15
all
- ubuntu•linux-gke-5.15
all
- ubuntu•linux-gke-5.4
all
- ubuntu•linux-gkeop
< 5.4.0-1015.16
- ubuntu•linux-gkeop-5.4
all
- ubuntu•linux-hwe
< 4.15.0-144.148~16.04.1 | all
- ubuntu•linux-hwe-5.11
all
Showing first 50 affected entries in server-rendered view.
References (8)
- https://ubuntu.com/security/CVE-2021-4442
- https://www.cve.org/CVERecord?id=CVE-2021-4442
- https://git.kernel.org/linus/8811f4a9836e31c14ecdf79d9f3cb7c5d463265d
- https://git.kernel.org/stable/c/319f460237fc2965a80aa9a055044e1da7b3692a
- https://git.kernel.org/stable/c/3bf899438c123c444f6b644a57784dfbb6b15ad6
- https://git.kernel.org/stable/c/046f3c1c2ff450fb7ae53650e9a95e0074a61f3e
- https://git.kernel.org/stable/c/3b72d5a703842f582502d97906f17d6ee122dac2
- https://git.kernel.org/stable/c/8811f4a9836e31c14ecdf79d9f3cb7c5d463265d