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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: 0 PID: 16420 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]
 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_compat_sys_sendfile fs/read_write.c:1603 [inline]
 __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1586
 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1586
 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: 0023:0xf7f30dd9
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:00000000f5d2b0cc EFLAGS: 00000296 ORIG_RAX: 00000000000000bb
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000005
RDX: 0000000000000000 RSI: 00000000fffffffe 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
 ___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_compat_sys_sendfile fs/read_write.c:1603 [inline]
 __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1586
 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1586
 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
 __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_compat_sys_sendfile fs/read_write.c:1603 [inline]
 __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1586
 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1586
 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

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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