SecuriTricks - CVE-2021-4442

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.

Product(s) Impacted

Vendor	Product	Versions
Linux	Linux Kernel	*, 5.12

Weaknesses

Common security weaknesses mapped to this vulnerability.

*CPE(s)

Affected systems and software identified for this CVE.

Type	Vendor	Product	Version	Update	Edition	Language	Software Edition	Target Software	Target Hardware	Other Information
o	linux	linux_kernel	/	/	/	/	/	/	/	/
o	linux	linux_kernel	/	/	/	/	/	/	/	/
o	linux	linux_kernel	/	/	/	/	/	/	/	/
o	linux	linux_kernel	/	/	/	/	/	/	/	/
o	linux	linux_kernel	5.12	rc1	/	/	/	/	/	/
o	linux	linux_kernel	5.12	rc2	/	/	/	/	/	/

References

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

CVSS Score

5.5 / 10

CVSS Data - 3.1

Attack Vector: LOCAL
Attack Complexity: LOW
Privileges Required: LOW
Scope: UNCHANGED
Confidentiality Impact: NONE
Integrity Impact: NONE
Availability Impact: HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

View Vector String

Timeline

Published: Aug. 29, 2024, 11:15 a.m.
Last Modified: Sept. 12, 2024, 4:58 p.m.

Status : Analyzed

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

416baaa9-dc9f-4396-8d5f-8c081fb06d67

CVE-2021-4442