CVE-2023-53433 — linux / linux_kernel
In the Linux kernel, the following vulnerability has been resolved:
net: add vlan_get_protocol_and_depth() helper
Before blamed commit, pskb_may_pull() was used instead of skb_header_pointer() in __vlan_get_protocol() and friends.
Few callers depended on skb->head being populated with MAC header, syzbot caught one of them (skb_mac_gso_segment())
Add vlan_get_protocol_and_depth() to make the intent clearer and use it where sensible.
This is a more generic fix than commit e9d3f80935b6 ("net/af_packet: make sure to pull mac header") which was dealing with a similar issue.
kernel BUG at include/linux/skbuff.h:2655 ! invalid opcode: 0000 [#1] SMP KASAN CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline] RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136 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 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286 RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012 R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7 FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> [<ffffffff847018dd>] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419 [<ffffffff8470398a>] skb_gso_segment include/linux/netdevice.h:4819 [inline] [<ffffffff8470398a>] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725 [<ffffffff84707042>] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313 [<ffffffff851a9ec7>] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029 [<ffffffff851b4a82>] packet_snd net/packet/af_packet.c:3111 [inline] [<ffffffff851b4a82>] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142 [<ffffffff84669a12>] sock_sendmsg_nosec net/socket.c:716 [inline] [<ffffffff84669a12>] sock_sendmsg net/socket.c:736 [inline] [<ffffffff84669a12>] __sys_sendto+0x472/0x5f0 net/socket.c:2139 [<ffffffff84669c75>] __do_sys_sendto net/socket.c:2151 [inline] [<ffffffff84669c75>] __se_sys_sendto net/socket.c:2147 [inline] [<ffffffff84669c75>] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147 [<ffffffff8551d40f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff8551d40f>] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80 [<ffffffff85600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 4.4.248 | 4.5 |
| linux / linux_kernel | 4.9.248 | 4.10 |
| linux / linux_kernel | 4.14.212 | 4.15 |
| linux / linux_kernel | 4.19.134 | 4.20 |
| linux / linux_kernel | 5.4.53 | 5.4.244 |
| linux / linux_kernel | 5.7.10 | 5.8 |
| linux / linux_kernel | 5.8.1 | 5.10.181 |
| linux / linux_kernel | 5.11 | 5.15.113 |
| linux / linux_kernel | 5.16 | 6.1.30 |
| linux / linux_kernel | 6.2 | 6.3.4 |
| linux / linux_kernel | 5.8 | 5.8.x |
| linux / linux_kernel | 5.8-rc5 | 5.8-rc5.x |
| linux / linux_kernel | 5.8-rc6 | 5.8-rc6.x |
| linux / linux_kernel | 5.8-rc7 | 5.8-rc7.x |
| linux / linux_kernel | 6.4-rc1 | 6.4-rc1.x |
- https://git.kernel.org/stable/c/15eaeb8941f12fcc2713c4bf6eb8f76a37854b4d
- https://git.kernel.org/stable/c/34a5ee69ec6273f0aee79e7ce4d14afc83ca8122
- https://git.kernel.org/stable/c/4063384ef762cc5946fc7a3f89879e76c6ec51e2
- https://git.kernel.org/stable/c/4188c5269475ac59d467b5814c5df02756f6d907
- https://git.kernel.org/stable/c/55caf900e13cd04466def08173a14b41d18c19c3
- https://git.kernel.org/stable/c/9dd9ffe118415b4ac1cebac43443000072bc8f46
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