Improper Input Validation Affecting kernel-tools package, versions <0:4.18.0-348.el8
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Test your applications- Snyk ID SNYK-RHEL8-KERNELTOOLS-7854587
- published 30 Aug 2024
- disclosed 29 Aug 2024
Introduced: 29 Aug 2024
CVE-2021-4442 Open this link in a new tabHow to fix?
Upgrade RHEL:8 kernel-tools to version 0:4.18.0-348.el8 or higher.
This issue was patched in RHSA-2021:4356.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-tools package and not the kernel-tools package as distributed by RHEL.
See How to fix? for RHEL:8 relevant fixed versions and status.
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://access.redhat.com/security/cve/CVE-2021-4442
- https://git.kernel.org/stable/c/046f3c1c2ff450fb7ae53650e9a95e0074a61f3e
- https://git.kernel.org/stable/c/319f460237fc2965a80aa9a055044e1da7b3692a
- https://git.kernel.org/stable/c/3b72d5a703842f582502d97906f17d6ee122dac2
- https://git.kernel.org/stable/c/3bf899438c123c444f6b644a57784dfbb6b15ad6
- https://git.kernel.org/stable/c/8811f4a9836e31c14ecdf79d9f3cb7c5d463265d