===================================================== BUG: KMSAN: uninit-value in ____bpf_skb_get_nlattr_nest net/core/filter.c:164 [inline] BUG: KMSAN: uninit-value in bpf_skb_get_nlattr_nest+0x14c/0x2f0 net/core/filter.c:154 CPU: 1 PID: 13405 Comm: syz-executor.4 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 ____bpf_skb_get_nlattr_nest net/core/filter.c:164 [inline] bpf_skb_get_nlattr_nest+0x14c/0x2f0 net/core/filter.c:154 ___bpf_prog_run+0x214d/0x97a0 kernel/bpf/core.c:1516 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline] __bpf_prog_run_save_cb include/linux/filter.h:693 [inline] bpf_prog_run_save_cb include/linux/filter.h:707 [inline] sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119 sk_filter include/linux/filter.h:833 [inline] unix_dgram_sendmsg+0x1987/0x3c30 net/unix/af_unix.c:1710 unix_seqpacket_sendmsg+0x26c/0x2e0 net/unix/af_unix.c:2063 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_sendmmsg+0x5fe/0xd60 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2532 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2532 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ca29 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f93f206fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00000000004fc580 RCX: 000000000045ca29 RDX: 0000000000000002 RSI: 0000000020003340 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000008dd R14: 00000000004cba1f R15: 00007f93f20706d4 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 ___bpf_prog_run+0x6cbe/0x97a0 kernel/bpf/core.c:1391 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline] __bpf_prog_run_save_cb include/linux/filter.h:693 [inline] bpf_prog_run_save_cb include/linux/filter.h:707 [inline] sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119 sk_filter include/linux/filter.h:833 [inline] unix_dgram_sendmsg+0x1987/0x3c30 net/unix/af_unix.c:1710 unix_seqpacket_sendmsg+0x26c/0x2e0 net/unix/af_unix.c:2063 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_sendmmsg+0x5fe/0xd60 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2532 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2532 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x44/0xa9 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 ___bpf_prog_run+0x6c64/0x97a0 kernel/bpf/core.c:1391 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline] __bpf_prog_run_save_cb include/linux/filter.h:693 [inline] bpf_prog_run_save_cb include/linux/filter.h:707 [inline] sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119 sk_filter include/linux/filter.h:833 [inline] unix_dgram_sendmsg+0x1987/0x3c30 net/unix/af_unix.c:1710 unix_seqpacket_sendmsg+0x26c/0x2e0 net/unix/af_unix.c:2063 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_sendmmsg+0x5fe/0xd60 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2532 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2532 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Local variable ----regs@__bpf_prog_run32 created at: __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681 =====================================================