Hello, syzbot found the following crash on: HEAD commit: f0d5ec90 kmsan: apply __no_sanitize_memory to dotraplinkag.. git tree: https://github.com/google/kmsan.git master console output: https://syzkaller.appspot.com/x/log.txt?x=17927f2e100000 kernel config: https://syzkaller.appspot.com/x/.config?x=86e4f8af239686c6 dashboard link: https://syzkaller.appspot.com/bug?extid=81b3ea575b0ab527b8b4 compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) userspace arch: i386 Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+81b3ea575b0ab527b8b4@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in __read_once_size include/linux/compiler.h:206 [inline] BUG: KMSAN: uninit-value in hash_ip6_del+0x92b/0x1d30 net/netfilter/ipset/ip_set_hash_gen.h:1069 CPU: 1 PID: 19407 Comm: syz-executor.1 Not tainted 5.7.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 __read_once_size include/linux/compiler.h:206 [inline] hash_ip6_del+0x92b/0x1d30 net/netfilter/ipset/ip_set_hash_gen.h:1069 hash_ip6_uadt+0x8e6/0xad0 net/netfilter/ipset/ip_set_hash_ip.c:267 call_ad+0x2dc/0xbc0 net/netfilter/ipset/ip_set_core.c:1732 ip_set_ad+0xad2/0x1110 net/netfilter/ipset/ip_set_core.c:1820 ip_set_udel+0xf9/0x110 net/netfilter/ipset/ip_set_core.c:1854 nfnetlink_rcv_msg+0xb86/0xcf0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2469 nfnetlink_rcv+0x3b5/0x3ab0 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x1246/0x14d0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2362 ___sys_sendmsg net/socket.c:2416 [inline] __sys_sendmsg+0x623/0x750 net/socket.c:2449 __compat_sys_sendmsg net/compat.c:658 [inline] __do_compat_sys_sendmsg net/compat.c:665 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:662 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:662 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline] do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fe3dd9 Code: 90 e8 0b 00 00 00 f3 90 0f ae e8 eb f9 8d 74 26 00 89 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5dde0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200002c0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165 ip6_netmask include/linux/netfilter/ipset/pfxlen.h:49 [inline] hash_ip6_netmask net/netfilter/ipset/ip_set_hash_ip.c:185 [inline] hash_ip6_uadt+0x9df/0xad0 net/netfilter/ipset/ip_set_hash_ip.c:263 call_ad+0x2dc/0xbc0 net/netfilter/ipset/ip_set_core.c:1732 ip_set_ad+0xad2/0x1110 net/netfilter/ipset/ip_set_core.c:1820 ip_set_udel+0xf9/0x110 net/netfilter/ipset/ip_set_core.c:1854 nfnetlink_rcv_msg+0xb86/0xcf0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2469 nfnetlink_rcv+0x3b5/0x3ab0 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x1246/0x14d0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2362 ___sys_sendmsg net/socket.c:2416 [inline] __sys_sendmsg+0x623/0x750 net/socket.c:2449 __compat_sys_sendmsg net/compat.c:658 [inline] __do_compat_sys_sendmsg net/compat.c:665 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:662 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:662 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline] do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116 ip_set_get_ipaddr6+0x26a/0x300 net/netfilter/ipset/ip_set_core.c:325 hash_ip6_uadt+0x450/0xad0 net/netfilter/ipset/ip_set_hash_ip.c:255 call_ad+0x2dc/0xbc0 net/netfilter/ipset/ip_set_core.c:1732 ip_set_ad+0xad2/0x1110 net/netfilter/ipset/ip_set_core.c:1820 ip_set_udel+0xf9/0x110 net/netfilter/ipset/ip_set_core.c:1854 nfnetlink_rcv_msg+0xb86/0xcf0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2469 nfnetlink_rcv+0x3b5/0x3ab0 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x1246/0x14d0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2362 ___sys_sendmsg net/socket.c:2416 [inline] __sys_sendmsg+0x623/0x750 net/socket.c:2449 __compat_sys_sendmsg net/compat.c:658 [inline] __do_compat_sys_sendmsg net/compat.c:665 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:662 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:662 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline] do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2802 [inline] __kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4436 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1083 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1175 [inline] netlink_sendmsg+0x7d3/0x14d0 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2362 ___sys_sendmsg net/socket.c:2416 [inline] __sys_sendmsg+0x623/0x750 net/socket.c:2449 __compat_sys_sendmsg net/compat.c:658 [inline] __do_compat_sys_sendmsg net/compat.c:665 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:662 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:662 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline] do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139 ===================================================== --- This bug is generated by a bot. 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