===================================================== BUG: KMSAN: uninit-value in br_dev_xmit+0x88f/0x1b40 net/bridge/br_device.c:60 CPU: 1 PID: 12002 Comm: syz-executor.4 Tainted: G W 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x24c/0x2e0 lib/dump_stack.c:120 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197 br_dev_xmit+0x88f/0x1b40 net/bridge/br_device.c:60 __netdev_start_xmit include/linux/netdevice.h:4825 [inline] netdev_start_xmit include/linux/netdevice.h:4839 [inline] xmit_one+0x2b6/0x760 net/core/dev.c:3605 dev_hard_start_xmit net/core/dev.c:3621 [inline] __dev_queue_xmit+0x3432/0x4600 net/core/dev.c:4194 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4227 __bpf_tx_skb net/core/filter.c:2116 [inline] __bpf_redirect_common net/core/filter.c:2155 [inline] __bpf_redirect+0x1461/0x16b0 net/core/filter.c:2162 ____bpf_clone_redirect net/core/filter.c:2448 [inline] bpf_clone_redirect+0x4a1/0x660 net/core/filter.c:2420 ___bpf_prog_run+0x2b78/0xb950 kernel/bpf/core.c:1525 __bpf_prog_run512+0x12e/0x190 kernel/bpf/core.c:1750 bpf_test_run+0x53f/0xe60 include/linux/filter.h:770 bpf_prog_test_run_skb+0x1914/0x3500 net/bpf/test_run.c:582 bpf_prog_test_run kernel/bpf/syscall.c:3132 [inline] __do_sys_bpf+0xbe6f/0x1aba0 kernel/bpf/syscall.c:4411 __se_sys_bpf+0x8e/0xa0 kernel/bpf/syscall.c:4351 __ia32_sys_bpf+0x4a/0x70 kernel/bpf/syscall.c:4351 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x127/0x180 arch/x86/entry/common.c:142 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:168 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:211 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f92549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f558c5fc EFLAGS: 00000296 ORIG_RAX: 0000000000000165 RAX: ffffffffffffffda RBX: 000000000000000a RCX: 00000000200000c0 RDX: 0000000000000048 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:120 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:103 kmsan_slab_alloc+0x8e/0xe0 mm/kmsan/kmsan_hooks.c:76 slab_alloc_node mm/slub.c:2922 [inline] __kmalloc_node_track_caller+0xa4f/0x1470 mm/slub.c:4609 kmalloc_reserve net/core/skbuff.c:353 [inline] pskb_expand_head+0x25e/0x1e20 net/core/skbuff.c:1676 skb_ensure_writable+0x4cf/0x590 net/core/skbuff.c:5565 __bpf_try_make_writable net/core/filter.c:1654 [inline] bpf_try_make_writable net/core/filter.c:1660 [inline] bpf_try_make_head_writable net/core/filter.c:1668 [inline] ____bpf_clone_redirect net/core/filter.c:2442 [inline] bpf_clone_redirect+0x25d/0x660 net/core/filter.c:2420 ___bpf_prog_run+0x2b78/0xb950 kernel/bpf/core.c:1525 __bpf_prog_run512+0x12e/0x190 kernel/bpf/core.c:1750 bpf_test_run+0x53f/0xe60 include/linux/filter.h:770 bpf_prog_test_run_skb+0x1914/0x3500 net/bpf/test_run.c:582 bpf_prog_test_run kernel/bpf/syscall.c:3132 [inline] __do_sys_bpf+0xbe6f/0x1aba0 kernel/bpf/syscall.c:4411 __se_sys_bpf+0x8e/0xa0 kernel/bpf/syscall.c:4351 __ia32_sys_bpf+0x4a/0x70 kernel/bpf/syscall.c:4351 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x127/0x180 arch/x86/entry/common.c:142 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:168 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:211 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================