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