================================================================== BUG: KASAN: slab-out-of-bounds in do_csum+0x2cd/0x2e0 lib/checksum.c:73 Read of size 4 at addr ffff8880253a6080 by task syz-executor.0/11855 CPU: 1 PID: 11855 Comm: syz-executor.0 Not tainted 6.6.0-rc4-syzkaller-00284-gb9ddbb0cde2a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 do_csum+0x2cd/0x2e0 lib/checksum.c:73 csum_partial+0x23/0x50 lib/checksum.c:128 gso_make_checksum include/net/gso.h:74 [inline] __skb_udp_tunnel_segment net/ipv4/udp_offload.c:140 [inline] skb_udp_tunnel_segment+0x126b/0x1ff0 net/ipv4/udp_offload.c:182 udp6_ufo_fragment+0x9f1/0xd50 net/ipv6/udp_offload.c:35 ipv6_gso_segment+0x5c4/0x17b0 net/ipv6/ip6_offload.c:120 skb_mac_gso_segment+0x290/0x610 net/core/gso.c:53 __skb_gso_segment+0x339/0x710 net/core/gso.c:124 skb_gso_segment include/net/gso.h:83 [inline] validate_xmit_skb+0x3a5/0xf10 net/core/dev.c:3625 __dev_queue_xmit+0x8e6/0x3d60 net/core/dev.c:4332 dev_queue_xmit include/linux/netdevice.h:3082 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1583 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0x584/0x1700 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x1250 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip6_output+0x1e2/0x530 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] ip6_local_out+0xaf/0x190 net/ipv6/output_core.c:155 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline] udp_tunnel6_xmit_skb+0x741/0xb70 net/ipv6/ip6_udp_tunnel.c:109 geneve6_xmit_skb drivers/net/geneve.c:1071 [inline] geneve_xmit+0x1b91/0x4aa0 drivers/net/geneve.c:1100 __netdev_start_xmit include/linux/netdevice.h:4889 [inline] netdev_start_xmit include/linux/netdevice.h:4903 [inline] xmit_one net/core/dev.c:3544 [inline] dev_hard_start_xmit+0x13d/0x6c0 net/core/dev.c:3560 __dev_queue_xmit+0x9b4/0x3d60 net/core/dev.c:4340 dev_queue_xmit include/linux/netdevice.h:3082 [inline] packet_xmit+0x257/0x380 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3087 [inline] packet_sendmsg+0x24d9/0x5580 net/packet/af_packet.c:3119 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] __se_sys_sendto net/socket.c:2202 [inline] __ia32_sys_sendto+0xdd/0x1b0 net/socket.c:2202 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7fb7579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7fb25ac EFLAGS: 00000292 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000280 RDX: 000000000000fc13 RSI: 0000000000000800 RDI: 0000000000000000 RBP: 000000000000002f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 11855: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x3f0 mm/slub.c:3523 kmalloc_reserve+0x166/0x260 net/core/skbuff.c:559 __alloc_skb+0x12b/0x330 net/core/skbuff.c:650 skb_segment+0x99c/0x4300 net/core/skbuff.c:4593 __udp_gso_segment+0x1496/0x1bf0 net/ipv4/udp_offload.c:298 udp4_ufo_fragment+0x510/0x700 net/ipv4/udp_offload.c:399 inet_gso_segment+0x548/0x12d0 net/ipv4/af_inet.c:1408 skb_mac_gso_segment+0x290/0x610 net/core/gso.c:53 __skb_udp_tunnel_segment net/ipv4/udp_offload.c:87 [inline] skb_udp_tunnel_segment+0x8e7/0x1ff0 net/ipv4/udp_offload.c:182 udp6_ufo_fragment+0x9f1/0xd50 net/ipv6/udp_offload.c:35 ipv6_gso_segment+0x5c4/0x17b0 net/ipv6/ip6_offload.c:120 skb_mac_gso_segment+0x290/0x610 net/core/gso.c:53 __skb_gso_segment+0x339/0x710 net/core/gso.c:124 skb_gso_segment include/net/gso.h:83 [inline] validate_xmit_skb+0x3a5/0xf10 net/core/dev.c:3625 __dev_queue_xmit+0x8e6/0x3d60 net/core/dev.c:4332 dev_queue_xmit include/linux/netdevice.h:3082 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1583 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0x584/0x1700 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x1250 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip6_output+0x1e2/0x530 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] ip6_local_out+0xaf/0x190 net/ipv6/output_core.c:155 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline] udp_tunnel6_xmit_skb+0x741/0xb70 net/ipv6/ip6_udp_tunnel.c:109 geneve6_xmit_skb drivers/net/geneve.c:1071 [inline] geneve_xmit+0x1b91/0x4aa0 drivers/net/geneve.c:1100 __netdev_start_xmit include/linux/netdevice.h:4889 [inline] netdev_start_xmit include/linux/netdevice.h:4903 [inline] xmit_one net/core/dev.c:3544 [inline] dev_hard_start_xmit+0x13d/0x6c0 net/core/dev.c:3560 __dev_queue_xmit+0x9b4/0x3d60 net/core/dev.c:4340 dev_queue_xmit include/linux/netdevice.h:3082 [inline] packet_xmit+0x257/0x380 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3087 [inline] packet_sendmsg+0x24d9/0x5580 net/packet/af_packet.c:3119 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] __se_sys_sendto net/socket.c:2202 [inline] __ia32_sys_sendto+0xdd/0x1b0 net/socket.c:2202 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 The buggy address belongs to the object at ffff8880253a5e00 which belongs to the cache skbuff_small_head of size 640 The buggy address is located 0 bytes to the right of allocated 640-byte region [ffff8880253a5e00, ffff8880253a6080) The buggy address belongs to the physical page: page:ffffea000094e900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x253a4 head:ffffea000094e900 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff8881422438c0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5041, tgid 5035 (syz-fuzzer), ts 100860843509, free_ts 43615710255 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2297 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] kmem_cache_alloc_node+0x132/0x3f0 mm/slub.c:3523 kmalloc_reserve+0x166/0x260 net/core/skbuff.c:559 __alloc_skb+0x12b/0x330 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] __tcp_send_ack.part.0+0x64/0x730 net/ipv4/tcp_output.c:4055 __tcp_send_ack net/ipv4/tcp_output.c:4087 [inline] tcp_send_ack+0x82/0xa0 net/ipv4/tcp_output.c:4087 __tcp_ack_snd_check+0x156/0x9f0 net/ipv4/tcp_input.c:5570 tcp_ack_snd_check net/ipv4/tcp_input.c:5616 [inline] tcp_ack_snd_check net/ipv4/tcp_input.c:5610 [inline] tcp_rcv_established+0x932/0x1fa0 net/ipv4/tcp_input.c:6056 tcp_v4_do_rcv+0x669/0x9e0 net/ipv4/tcp_ipv4.c:1728 tcp_v4_rcv+0x33a9/0x3b40 net/ipv4/tcp_ipv4.c:2150 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x16c/0x3b0 mm/slub.c:3502 getname_flags.part.0+0x50/0x4d0 fs/namei.c:140 getname_flags include/linux/audit.h:321 [inline] getname+0x90/0xe0 fs/namei.c:219 do_sys_openat2+0x100/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8880253a5f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880253a6000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880253a6080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880253a6100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880253a6180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi