Bugzilla – Bug 1221650
VUL-0: CVE-2024-26640: kernel: tcp: add sanity checks to rx zerocopy
Last modified: 2024-04-25 15:45:38 UTC
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 can_map_frag() 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$inet_tcp(0x2, 0x1, 0x0) mmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0) r4 = socket$inet_tcp(0x2, 0x1, 0x0) bind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10) connect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10) r5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) fallocate(r5, 0x0, 0x0, 0x85b8) sendfile(r4, r5, 0x0, 0x8ba0) getsockopt$inet_tcp_TCP_ZEROCOPY_RECEIVE(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) References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-26640 https://git.kernel.org/stable/c/d15cc0f66884ef2bed28c7ccbb11c102aa3a0760 https://git.kernel.org/stable/c/f48bf9a83b1666d934247cb58a9887d7b3127b6f https://www.cve.org/CVERecord?id=CVE-2024-26640 https://git.kernel.org/stable/c/1b8adcc0e2c584fec778add7777fe28e20781e60 https://git.kernel.org/stable/c/577e4432f3ac810049cb7e6b71f4d96ec7c6e894 https://git.kernel.org/stable/c/718f446e60316bf606946f7f42367d691d21541e https://git.kernel.org/stable/c/b383d4ea272fe5795877506dcce5aad1f6330e5e https://bugzilla.redhat.com/show_bug.cgi?id=2270100
Affects SLE15-SP6, cve/linux-5.14 and cve/linux-5.3. Older branches are not affected.