CVE-2022-49142

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net: preserve skb_end_offset() in skb_unclone_keeptruesize()<br /> <br /> syzbot found another way to trigger the infamous WARN_ON_ONCE(delta truesize value,<br /> we also need to make sure TCP wont fill new tailroom<br /> that pskb_expand_head() was able to get from a<br /> addr = kmalloc(...) followed by ksize(addr)<br /> <br /> Split skb_unclone_keeptruesize() into two parts:<br /> <br /> 1) Inline skb_unclone_keeptruesize() for the common case,<br /> when skb is not cloned.<br /> <br /> 2) Out of line __skb_unclone_keeptruesize() for the &amp;#39;slow path&amp;#39;.<br /> <br /> WARNING: CPU: 1 PID: 6490 at net/core/skbuff.c:5295 skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295<br /> Modules linked in:<br /> CPU: 1 PID: 6490 Comm: syz-executor161 Not tainted 5.17.0-rc4-syzkaller-00229-g4f12b742eb2b #0<br /> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011<br /> RIP: 0010:skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295<br /> 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 0b e9 06 f9 ff ff e8 af b2 95 fa e9 69 f0 ff ff e8 95 b2 95 fa<br /> RSP: 0018:ffffc900063af268 EFLAGS: 00010293<br /> RAX: 0000000000000000 RBX: 00000000ffffffd5 RCX: 0000000000000000<br /> RDX: ffff88806fc05700 RSI: ffffffff872abd55 RDI: 0000000000000003<br /> RBP: ffff88806e675500 R08: 00000000ffffffd5 R09: 0000000000000000<br /> R10: ffffffff872ab659 R11: 0000000000000000 R12: ffff88806dd554e8<br /> R13: ffff88806dd9bac0 R14: ffff88806dd9a2c0 R15: 0000000000000155<br /> FS: 00007f18014f9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 0000000020002000 CR3: 000000006be7a000 CR4: 00000000003506f0<br /> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> Call Trace:<br /> <br /> tcp_try_coalesce net/ipv4/tcp_input.c:4651 [inline]<br /> tcp_try_coalesce+0x393/0x920 net/ipv4/tcp_input.c:4630<br /> tcp_queue_rcv+0x8a/0x6e0 net/ipv4/tcp_input.c:4914<br /> tcp_data_queue+0x11fd/0x4bb0 net/ipv4/tcp_input.c:5025<br /> tcp_rcv_established+0x81e/0x1ff0 net/ipv4/tcp_input.c:5947<br /> tcp_v4_do_rcv+0x65e/0x980 net/ipv4/tcp_ipv4.c:1719<br /> sk_backlog_rcv include/net/sock.h:1037 [inline]<br /> __release_sock+0x134/0x3b0 net/core/sock.c:2779<br /> release_sock+0x54/0x1b0 net/core/sock.c:3311<br /> sk_wait_data+0x177/0x450 net/core/sock.c:2821<br /> tcp_recvmsg_locked+0xe28/0x1fd0 net/ipv4/tcp.c:2457<br /> tcp_recvmsg+0x137/0x610 net/ipv4/tcp.c:2572<br /> inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:850<br /> sock_recvmsg_nosec net/socket.c:948 [inline]<br /> sock_recvmsg net/socket.c:966 [inline]<br /> sock_recvmsg net/socket.c:962 [inline]<br /> ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632<br /> ___sys_recvmsg+0x127/0x200 net/socket.c:2674<br /> __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704<br /> do_syscall_x64 arch/x86/entry/common.c:50 [inline]<br /> do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80<br /> entry_SYSCALL_64_after_hwframe+0x44/0xae