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BUG: KMSAN: uninit-value in sk_filter_trim_cap+0x828/0xcc0 net/core/filter.c:121
CPU: 0 PID: 14464 Comm: syz-executor.0 Not tainted 5.8.0-rc5-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+0x1df/0x240 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
 sk_filter_trim_cap+0x828/0xcc0 net/core/filter.c:121
 sk_filter include/linux/filter.h:831 [inline]
 sock_queue_rcv_skb+0x83/0x130 net/core/sock.c:487
 packet_rcv_spkt+0x656/0x7c0 net/packet/af_packet.c:1851
 dev_queue_xmit_nit+0x11a0/0x1280 net/core/dev.c:2355
 xmit_one net/core/dev.c:3552 [inline]
 dev_hard_start_xmit+0x20c/0xa70 net/core/dev.c:3572
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:294 [inline]
 __netlink_deliver_tap net/netlink/af_netlink.c:312 [inline]
 netlink_deliver_tap+0x9d4/0xe90 net/netlink/af_netlink.c:325
 netlink_deliver_tap_kernel net/netlink/af_netlink.c:334 [inline]
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xe87/0x1100 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+0x1370/0x1400 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmsg+0x623/0x750 net/socket.c:2439
 __do_sys_sendmsg net/socket.c:2448 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2446
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2446
 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x415e71
Code: Bad RIP value.
RSP: 002b:00007f2fdb39b9c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2fdb39ba40 RCX: 0000000000415e71
RDX: 0000000000000000 RSI: 00007f2fdb39ba00 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004
R13: 0000000000c9fb6f R14: 00007f2fdb39c9c0 R15: 000000000078bf0c

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:556 [inline]
 __bpf_prog_run_save_cb include/linux/filter.h:691 [inline]
 bpf_prog_run_save_cb include/linux/filter.h:705 [inline]
 sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119
 sk_filter include/linux/filter.h:831 [inline]
 sock_queue_rcv_skb+0x83/0x130 net/core/sock.c:487
 packet_rcv_spkt+0x656/0x7c0 net/packet/af_packet.c:1851
 dev_queue_xmit_nit+0x11a0/0x1280 net/core/dev.c:2355
 xmit_one net/core/dev.c:3552 [inline]
 dev_hard_start_xmit+0x20c/0xa70 net/core/dev.c:3572
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:294 [inline]
 __netlink_deliver_tap net/netlink/af_netlink.c:312 [inline]
 netlink_deliver_tap+0x9d4/0xe90 net/netlink/af_netlink.c:325
 netlink_deliver_tap_kernel net/netlink/af_netlink.c:334 [inline]
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xe87/0x1100 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+0x1370/0x1400 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmsg+0x623/0x750 net/socket.c:2439
 __do_sys_sendmsg net/socket.c:2448 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2446
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2446
 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386
 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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