CVE-2022-49142

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Last Modified: UTC

Low Low Impact What does this mean?
5.5 CVSS v3 Base Score

Description

The MITRE CVE dictionary describes this issue as

In the Linux kernel, the following vulnerability has been resolved: net: preserve skb_end_offset() in skb_unclone_keeptruesize() syzbot found another way to trigger the infamous WARN_ON_ONCE(delta < len) in skb_try_coalesce() [1] I was able to root cause the issue to kfence. When kfence is in action, the following assertion is no longer true: int size = xxxx; void *ptr1 = kmalloc(size, gfp); void *ptr2 = kmalloc(size, gfp); if (ptr1 && ptr2) ASSERT(ksize(ptr1) == ksize(ptr2)); We attempted to fix these issues in the blamed commits, but forgot that TCP was possibly shifting data after skb_unclone_keeptruesize() has been used, notably from tcp_retrans_try_collapse(). So we not only need to keep same skb->truesize value, we also need to make sure TCP wont fill new tailroom that pskb_expand_head() was able to get from a addr = kmalloc(...) followed by ksize(addr) Split skb_unclone_keeptruesize() into two parts: 1) Inline skb_unclone_keeptruesize() for the common case, when skb is not cloned. 2) Out of line __skb_unclone_keeptruesize() for the 'slow path'. WARNING: CPU: 1 PID: 6490 at net/core/skbuff.c:5295 skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295 Modules linked in: CPU: 1 PID: 6490 Comm: syz-executor161 Not tainted 5.17.0-rc4-syzkaller-00229-g4f12b742eb2b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295 Code: bf 01 00 00 00 0f b7 c0 89 c6 89 44 24 20 e8 62 24 4e fa 8b 44 24 20 83 e8 01 0f 85 e5 f0 ff ff e9 87 f4 ff ff e8 cb 20 4e fa <0f> 0b e9 06 f9 ff ff e8 af b2 95 fa e9 69 f0 ff ff e8 95 b2 95 fa RSP: 0018:ffffc900063af268 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 00000000ffffffd5 RCX: 0000000000000000 RDX: ffff88806fc05700 RSI: ffffffff872abd55 RDI: 0000000000000003 RBP: ffff88806e675500 R08: 00000000ffffffd5 R09: 0000000000000000 R10: ffffffff872ab659 R11: 0000000000000000 R12: ffff88806dd554e8 R13: ffff88806dd9bac0 R14: ffff88806dd9a2c0 R15: 0000000000000155 FS: 00007f18014f9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020002000 CR3: 000000006be7a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> tcp_try_coalesce net/ipv4/tcp_input.c:4651 [inline] tcp_try_coalesce+0x393/0x920 net/ipv4/tcp_input.c:4630 tcp_queue_rcv+0x8a/0x6e0 net/ipv4/tcp_input.c:4914 tcp_data_queue+0x11fd/0x4bb0 net/ipv4/tcp_input.c:5025 tcp_rcv_established+0x81e/0x1ff0 net/ipv4/tcp_input.c:5947 tcp_v4_do_rcv+0x65e/0x980 net/ipv4/tcp_ipv4.c:1719 sk_backlog_rcv include/net/sock.h:1037 [inline] __release_sock+0x134/0x3b0 net/core/sock.c:2779 release_sock+0x54/0x1b0 net/core/sock.c:3311 sk_wait_data+0x177/0x450 net/core/sock.c:2821 tcp_recvmsg_locked+0xe28/0x1fd0 net/ipv4/tcp.c:2457 tcp_recvmsg+0x137/0x610 net/ipv4/tcp.c:2572 inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:850 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_recvmsg net/socket.c:962 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632 ___sys_recvmsg+0x127/0x200 net/socket.c:2674 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2022-49142

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2022-49142

Content from lore.kernel.org is not included.https://lore.kernel.org/linux-cve-announce/2025022607-CVE-2022-49142-b3b9@gregkh/T

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
Red Hat Enterprise Linux 10 kernel Not affected
Red Hat Enterprise Linux 6 kernel Out of support scope
Red Hat Enterprise Linux 7 kernel Out of support scope
Red Hat Enterprise Linux 7 kernel-rt Out of support scope
Red Hat Enterprise Linux 8 kernel Not affected
Red Hat Enterprise Linux 8 kernel-rt Not affected
Red Hat Enterprise Linux 9 kernel-rt Fix deferred
Red Hat Enterprise Linux 9 kernel Fixed RHSA-2022:8267
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 5.5 5.5
Attack Vector Local Local
Attack Complexity Low Low
Privileges Required Low Low
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact None None
Integrity Impact None None
Availability Impact High High

CVSS v3 Vector

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

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

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

 For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

 A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

 A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

 A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

 The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

 In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.

My product is listed as "Out of Support Scope". What does this mean?

 When a product is listed as "Out of Support Scope", it means a vulnerability with the impact level assigned to this CVE is no longer covered by its current support lifecycle phase. The product has been identified to contain the impacted component, but analysis to determine whether it is affected or not by this vulnerability was not performed. The product should be assumed to be affected. Customers are advised to apply any mitigation options documented on this page, consider removing or disabling the impacted component, or upgrade to a supported version of the product that has an update available.