CVE-2024-26640: tcp: add sanity checks to rx zerocopy
In the Linux kernel, the following vulnerability has been resolved:
tcp: add sanity checks to rx zerocopy
TCP rx zerocopy intent is to map pages initially allocated from NIC drivers, not pages owned by a fs.
This patch adds to canmapfrag() these additional checks:
- Page must not be a compound one. - page->mapping must be NULL.
This fixes the panic reported by ZhangPeng.
syzbot was able to loopback packets built with sendfile(), mapping pages owned by an ext4 file to TCP rx zerocopy.
r3 = socket$inettcp(0x2, 0x1, 0x0) mmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0) r4 = socket$inettcp(0x2, 0x1, 0x0) bind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10) connect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10) r5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) fallocate(r5, 0x0, 0x0, 0x85b8) sendfile(r4, r5, 0x0, 0x8ba0) getsockopt$inettcpTCPZEROCOPYRECEIVE(r4, 0x6, 0x23, &(0x7f00000001c0)={&(0x7f0000ffb000/0x3000)=nil, 0x3000, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, &(0x7f0000000440)=0x40) r6 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0)
Other sources
In the Linux kernel, the following vulnerability has been resolved:
tcp: add sanity checks to rx zerocopy
The Linux kernel CVE team has assigned CVE-2024-26640 to this issue.
Upstream advisory: https://lore.kernel.org/linux-cve-announce/20240318102117.2839904-11-lee@kernel.org/T
— Red Hat
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-26640?
CVE-2024-26640 has a moderate severity rating due to its impact on the Linux kernel TCP zerocopy implementation.
How do I fix CVE-2024-26640?
To address CVE-2024-26640, update the Linux kernel to versions 5.10.210, 5.15.149, 6.1.77, 6.6.16, 6.7.4, or 6.8.
What does CVE-2024-26640 affect?
CVE-2024-26640 primarily affects the Linux kernel implementations related to TCP zerocopy.
What are the affected Linux kernel versions in CVE-2024-26640?
The affected Linux kernel versions for CVE-2024-26640 include those prior to 5.10.210, 5.15.149, 6.1.77, 6.6.16, 6.7.4, and 6.8.
When was CVE-2024-26640 published?
CVE-2024-26640 was published on March 7, 2024.