CVE-2023-53433

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net: add vlan_get_protocol_and_depth() helper<br /> <br /> Before blamed commit, pskb_may_pull() was used instead<br /> of skb_header_pointer() in __vlan_get_protocol() and friends.<br /> <br /> Few callers depended on skb-&gt;head being populated with MAC header,<br /> syzbot caught one of them (skb_mac_gso_segment())<br /> <br /> Add vlan_get_protocol_and_depth() to make the intent clearer<br /> and use it where sensible.<br /> <br /> This is a more generic fix than commit e9d3f80935b6<br /> ("net/af_packet: make sure to pull mac header") which was<br /> dealing with a similar issue.<br /> <br /> kernel BUG at include/linux/skbuff.h:2655 !<br /> invalid opcode: 0000 [#1] SMP KASAN<br /> CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0<br /> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023<br /> RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline]<br /> RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136<br /> Code: fd 48 8b 5c 24 10 44 89 6b 70 48 c7 c7 c0 ae 0d 86 44 89 e6 e8 a1 91 d0 00 48 c7 c7 00 af 0d 86 48 89 de 31 d2 e8 d1 4a e9 ff 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41<br /> RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286<br /> RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00<br /> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000<br /> RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9<br /> R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012<br /> R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7<br /> FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0<br /> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> Call Trace:<br /> <br /> [] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419<br /> [] skb_gso_segment include/linux/netdevice.h:4819 [inline]<br /> [] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725<br /> [] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313<br /> [] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029<br /> [] packet_snd net/packet/af_packet.c:3111 [inline]<br /> [] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142<br /> [] sock_sendmsg_nosec net/socket.c:716 [inline]<br /> [] sock_sendmsg net/socket.c:736 [inline]<br /> [] __sys_sendto+0x472/0x5f0 net/socket.c:2139<br /> [] __do_sys_sendto net/socket.c:2151 [inline]<br /> [] __se_sys_sendto net/socket.c:2147 [inline]<br /> [] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147<br /> [] do_syscall_x64 arch/x86/entry/common.c:50 [inline]<br /> [] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80<br /> [] entry_SYSCALL_64_after_hwframe+0x63/0xcd