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)
https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html
https://git.kernel.org/stable/c/f48bf9a83b1666d934247cb58a9887d7b3127b6f
https://git.kernel.org/stable/c/d15cc0f66884ef2bed28c7ccbb11c102aa3a0760
https://git.kernel.org/stable/c/b383d4ea272fe5795877506dcce5aad1f6330e5e
https://git.kernel.org/stable/c/718f446e60316bf606946f7f42367d691d21541e
https://git.kernel.org/stable/c/577e4432f3ac810049cb7e6b71f4d96ec7c6e894
https://git.kernel.org/stable/c/1b8adcc0e2c584fec778add7777fe28e20781e60