In the Linux kernel, the following vulnerability has been resolved:
veth: ensure skb entering GRO are not cloned.
After commit d3256efd8e8b ("veth: allow enabling NAPI even without XDP"), if GRO is enabled on a veth device and TSO is disabled on the peer device, TCP skbs will go through the NAPI callback. If there is no XDP program attached, the veth code does not perform any share check, and shared/cloned skbs could enter the GRO engine.
Ignat reported a BUG triggered later-on due to the above condition:
[ 53.970529][ C1] kernel BUG at net/core/skbuff.c:3574! [ 53.981755][ C1] invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI [ 53.982634][ C1] CPU: 1 PID: 19 Comm: ksoftirqd/1 Not tainted 5.16.0-rc5+ #25 [ 53.982634][ C1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 53.982634][ C1] RIP: 0010:skb_shift+0x13ef/0x23b0 [ 53.982634][ C1] Code: ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 41 0c 00 00 41 80 7f 02 00 4d 8d b5 d0 00 00 00 0f 85 74 f5 ff ff <0f> 0b 4d 8d 77 20 be 04 00 00 00 4c 89 44 24 78 4c 89 f7 4c 89 8c [ 53.982634][ C1] RSP: 0018:ffff8881008f7008 EFLAGS: 00010246 [ 53.982634][ C1] RAX: 0000000000000000 RBX: ffff8881180b4c80 RCX: 0000000000000000 [ 53.982634][ C1] RDX: 0000000000000002 RSI: ffff8881180b4d3c RDI: ffff88810bc9cac2 [ 53.982634][ C1] RBP: ffff8881008f70b8 R08: ffff8881180b4cf4 R09: ffff8881180b4cf0 [ 53.982634][ C1] R10: ffffed1022999e5c R11: 0000000000000002 R12: 0000000000000590 [ 53.982634][ C1] R13: ffff88810f940c80 R14: ffff88810f940d50 R15: ffff88810bc9cac0 [ 53.982634][ C1] FS: 0000000000000000(0000) GS:ffff888235880000(0000) knlGS:0000000000000000 [ 53.982634][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 53.982634][ C1] CR2: 00007ff5f9b86680 CR3: 0000000108ce8004 CR4: 0000000000170ee0 [ 53.982634][ C1] Call Trace: [ 53.982634][ C1] <TASK> [ 53.982634][ C1] tcp_sacktag_walk+0xaba/0x18e0 [ 53.982634][ C1] tcp_sacktag_write_queue+0xe7b/0x3460 [ 53.982634][ C1] tcp_ack+0x2666/0x54b0 [ 53.982634][ C1] tcp_rcv_established+0x4d9/0x20f0 [ 53.982634][ C1] tcp_v4_do_rcv+0x551/0x810 [ 53.982634][ C1] tcp_v4_rcv+0x22ed/0x2ed0 [ 53.982634][ C1] ip_protocol_deliver_rcu+0x96/0xaf0 [ 53.982634][ C1] ip_local_deliver_finish+0x1e0/0x2f0 [ 53.982634][ C1] ip_sublist_rcv_finish+0x211/0x440 [ 53.982634][ C1] ip_list_rcv_finish.constprop.0+0x424/0x660 [ 53.982634][ C1] ip_list_rcv+0x2c8/0x410 [ 53.982634][ C1] __netif_receive_skb_list_core+0x65c/0x910 [ 53.982634][ C1] netif_receive_skb_list_internal+0x5f9/0xcb0 [ 53.982634][ C1] napi_complete_done+0x188/0x6e0 [ 53.982634][ C1] gro_cell_poll+0x10c/0x1d0 [ 53.982634][ C1] __napi_poll+0xa1/0x530 [ 53.982634][ C1] net_rx_action+0x567/0x1270 [ 53.982634][ C1] __do_softirq+0x28a/0x9ba [ 53.982634][ C1] run_ksoftirqd+0x32/0x60 [ 53.982634][ C1] smpboot_thread_fn+0x559/0x8c0 [ 53.982634][ C1] kthread+0x3b9/0x490 [ 53.982634][ C1] ret_from_fork+0x22/0x30 [ 53.982634][ C1] </TASK>
Address the issue by skipping the GRO stage for shared or cloned skbs. To reduce the chance of OoO, try to unclone the skbs before giving up.
v1 -> v2: - use avoid skb_copy and fallback to netif_receive_skb - Eric
CVSS Details
- CVSS 3.1 Base Score: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade linux | Jul 30, 2024 | Mar 4, 2024 |
| Redhat_linux | — | No solution existsUpgrade kernel | Apr 19, 2024 | Mar 4, 2024 |
| Suse | — | Upgrade kernel-azure-vdsoUpgrade dtb-caviumUpgrade kernel-syms-rtUpgrade kernel-source-azureUpgrade dtb-hisiliconUpgrade dtb-appleUpgrade gfs2-kmp-azureUpgrade ocfs2-kmp-64kbUpgrade kernel-64kbUpgrade dlm-kmp-defaultUpgrade dlm-kmp-64kbUpgrade kernel-debugUpgrade kernel-rt-vdsoUpgrade dtb-marvellUpgrade kselftests-kmp-azureUpgrade dtb-amlogicUpgrade kernel-rt_debug-vdsoUpgrade dtb-socionextUpgrade kernel-kvmsmall-livepatch-develUpgrade kernel-source-vanillaUpgrade dtb-amdUpgrade reiserfs-kmp-rtUpgrade kernel-64kb-livepatch-develUpgrade ocfs2-kmp-rtUpgrade kernel-zfcpdumpUpgrade kernel-default-livepatch-develUpgrade dtb-broadcomUpgrade kernel-64kb-optionalUpgrade gfs2-kmp-64kbUpgrade dtb-alteraUpgrade kernel-source-rtUpgrade kernel-default-baseUpgrade kernel-docs-htmlUpgrade ocfs2-kmp-azureUpgrade kernel-azureUpgrade kernel-rt-optionalUpgrade kernel-rt_debug-livepatch-develUpgrade kselftests-kmp-64kbUpgrade kernel-azure-optionalUpgrade kernel-debug-develUpgrade kernel-rt_debugUpgrade kernel-rt-livepatch-develUpgrade dtb-amazonUpgrade dtb-freescaleUpgrade cluster-md-kmp-azureUpgrade dtb-lgUpgrade kernel-kvmsmall-develUpgrade reiserfs-kmp-defaultUpgrade kernel-azure-extraUpgrade gfs2-kmp-rtUpgrade kernel-symsUpgrade kernel-default-develUpgrade kernel-rt_debug-develUpgrade reiserfs-kmp-64kbUpgrade dtb-renesasUpgrade kernel-kvmsmall-vdsoUpgrade kernel-default-livepatchUpgrade kernel-kvmsmallUpgrade kernel-debug-livepatch-develUpgrade kernel-obs-buildUpgrade gfs2-kmp-defaultUpgrade kernel-devel-azureUpgrade kernel-debug-vdsoUpgrade dtb-exynosUpgrade kernel-rtUpgrade kernel-devel-rtUpgrade kernel-develUpgrade cluster-md-kmp-defaultUpgrade kernel-sourceUpgrade kernel-64kb-extraUpgrade kernel-64kb-develUpgrade kernel-rt-livepatchUpgrade dtb-allwinnerUpgrade kernel-default-optionalUpgrade dtb-apmUpgrade dtb-sprdUpgrade dtb-mediatekUpgrade dtb-rockchipUpgrade kernel-rt-extraUpgrade kernel-obs-qaUpgrade kernel-default-extraUpgrade kernel-macrosUpgrade cluster-md-kmp-64kbUpgrade kernel-azure-livepatch-develUpgrade dtb-armUpgrade kernel-rt-develUpgrade dlm-kmp-azureUpgrade kernel-azure-develUpgrade dtb-xilinxUpgrade kselftests-kmp-rtUpgrade kernel-default-base-rebuildUpgrade dtb-nvidiaUpgrade dlm-kmp-rtUpgrade kernel-syms-azureUpgrade kernel-defaultUpgrade reiserfs-kmp-azureUpgrade cluster-md-kmp-rtUpgrade dtb-qcomUpgrade kselftests-kmp-defaultUpgrade kernel-docsUpgrade kernel-default-vdsoUpgrade ocfs2-kmp-default | Aug 9, 2024 | Mar 4, 2024 |
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