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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: 19448 Comm: syz-executor.2 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]
 kernel_sendmsg+0x433/0x440 net/socket.c:692
 sock_no_sendpage+0x235/0x300 net/core/sock.c:2763
 kernel_sendpage net/socket.c:3808 [inline]
 sock_sendpage+0x1e1/0x2c0 net/socket.c:950
 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x539/0xed0 fs/splice.c:636
 splice_from_pipe fs/splice.c:671 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x19e/0x200 fs/splice.c:1037
 splice_direct_to_actor+0x8a9/0x11e0 fs/splice.c:992
 do_splice_direct+0x342/0x580 fs/splice.c:1080
 do_sendfile+0x101b/0x1d40 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64+0x2bb/0x360 fs/read_write.c:1568
 __x64_sys_sendfile64+0x56/0x70 fs/read_write.c:1568
 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:00007efe92300c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004fc540 RCX: 000000000045ca29
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 00008000fffffffe R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008dc R14: 00000000004cba16 R15: 00007efe923016d4

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]
 kernel_sendmsg+0x433/0x440 net/socket.c:692
 sock_no_sendpage+0x235/0x300 net/core/sock.c:2763
 kernel_sendpage net/socket.c:3808 [inline]
 sock_sendpage+0x1e1/0x2c0 net/socket.c:950
 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x539/0xed0 fs/splice.c:636
 splice_from_pipe fs/splice.c:671 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x19e/0x200 fs/splice.c:1037
 splice_direct_to_actor+0x8a9/0x11e0 fs/splice.c:992
 do_splice_direct+0x342/0x580 fs/splice.c:1080
 do_sendfile+0x101b/0x1d40 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64+0x2bb/0x360 fs/read_write.c:1568
 __x64_sys_sendfile64+0x56/0x70 fs/read_write.c:1568
 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]
 kernel_sendmsg+0x433/0x440 net/socket.c:692
 sock_no_sendpage+0x235/0x300 net/core/sock.c:2763
 kernel_sendpage net/socket.c:3808 [inline]
 sock_sendpage+0x1e1/0x2c0 net/socket.c:950
 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x539/0xed0 fs/splice.c:636
 splice_from_pipe fs/splice.c:671 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x19e/0x200 fs/splice.c:1037
 splice_direct_to_actor+0x8a9/0x11e0 fs/splice.c:992
 do_splice_direct+0x342/0x580 fs/splice.c:1080
 do_sendfile+0x101b/0x1d40 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64+0x2bb/0x360 fs/read_write.c:1568
 __x64_sys_sendfile64+0x56/0x70 fs/read_write.c:1568
 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
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