================================================================== BUG: KMSAN: uninit-value in do_slab_free mm/slub.c:3016 [inline] BUG: KMSAN: uninit-value in slab_free mm/slub.c:3039 [inline] BUG: KMSAN: uninit-value in kmem_cache_free+0x3df/0x2b70 mm/slub.c:3054 CPU: 0 PID: 12008 Comm: syz-fuzzer Not tainted 5.3.0-rc3+ #17 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+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294 do_slab_free mm/slub.c:3016 [inline] slab_free mm/slub.c:3039 [inline] kmem_cache_free+0x3df/0x2b70 mm/slub.c:3054 kfree_skbmem net/core/skbuff.c:644 [inline] __kfree_skb net/core/skbuff.c:680 [inline] kfree_skb+0x473/0x4c0 net/core/skbuff.c:697 packet_rcv_spkt+0x719/0x840 net/packet/af_packet.c:1847 dev_queue_xmit_nit+0x1125/0x1200 net/core/dev.c:2077 xmit_one net/core/dev.c:3276 [inline] dev_hard_start_xmit+0x21e/0xab0 net/core/dev.c:3296 sch_direct_xmit+0x56c/0x18c0 net/sched/sch_generic.c:309 __dev_xmit_skb net/core/dev.c:3477 [inline] __dev_queue_xmit+0x1e53/0x4270 net/core/dev.c:3838 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip_finish_output2+0x20c6/0x25d0 net/ipv4/ip_output.c:228 __ip_finish_output+0xaf8/0xda0 net/ipv4/ip_output.c:308 ip_finish_output+0x2db/0x420 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0x541/0x610 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] __ip_queue_xmit+0x1caf/0x21f0 net/ipv4/ip_output.c:532 ip_queue_xmit+0xcc/0xf0 include/net/ip.h:236 __tcp_transmit_skb+0x409e/0x5c60 net/ipv4/tcp_output.c:1158 __tcp_send_ack+0x701/0x840 net/ipv4/tcp_output.c:3681 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3687 tcp_cleanup_rbuf+0x764/0x800 net/ipv4/tcp.c:1562 tcp_recvmsg+0x334d/0x4ff0 net/ipv4/tcp.c:2166 inet_recvmsg+0x237/0x7d0 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_read_iter+0x5be/0x660 net/socket.c:967 call_read_iter include/linux/fs.h:1864 [inline] new_sync_read fs/read_write.c:414 [inline] __vfs_read+0xa67/0xc90 fs/read_write.c:427 vfs_read+0x359/0x6f0 fs/read_write.c:461 ksys_read+0x265/0x430 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read+0x92/0xb0 fs/read_write.c:595 __x64_sys_read+0x4a/0x70 fs/read_write.c:595 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x47fcb4 Code: ff ff cc cc cc cc e8 2b 41 fb ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 45 31 d2 45 31 c0 45 31 c9 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 RSP: 002b:000000c42014b710 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047fcb4 RDX: 0000000000001000 RSI: 000000c4202c8000 RDI: 0000000000000003 RBP: 000000c42014b760 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008 R13: 0000000000000008 R14: 0000000000000004 R15: ffffffffffffffff Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:187 [inline] kmsan_internal_chain_origin+0xcc/0x150 mm/kmsan/kmsan.c:345 __msan_chain_origin+0x6b/0xe0 mm/kmsan/kmsan_instr.c:190 ___slab_alloc+0x1dbc/0x1fb0 mm/slub.c:2634 __slab_alloc mm/slub.c:2687 [inline] slab_alloc_node mm/slub.c:2750 [inline] slab_alloc mm/slub.c:2799 [inline] kmem_cache_alloc+0xade/0xd10 mm/slub.c:2804 skb_clone+0x326/0x5d0 net/core/skbuff.c:1448 dev_queue_xmit_nit+0x539/0x1200 net/core/dev.c:2045 xmit_one net/core/dev.c:3276 [inline] dev_hard_start_xmit+0x21e/0xab0 net/core/dev.c:3296 sch_direct_xmit+0x56c/0x18c0 net/sched/sch_generic.c:309 __dev_xmit_skb net/core/dev.c:3477 [inline] __dev_queue_xmit+0x1e53/0x4270 net/core/dev.c:3838 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip_finish_output2+0x20c6/0x25d0 net/ipv4/ip_output.c:228 __ip_finish_output+0xaf8/0xda0 net/ipv4/ip_output.c:308 ip_finish_output+0x2db/0x420 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0x541/0x610 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] __ip_queue_xmit+0x1caf/0x21f0 net/ipv4/ip_output.c:532 ip_queue_xmit+0xcc/0xf0 include/net/ip.h:236 __tcp_transmit_skb+0x409e/0x5c60 net/ipv4/tcp_output.c:1158 __tcp_send_ack+0x701/0x840 net/ipv4/tcp_output.c:3681 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3687 tcp_cleanup_rbuf+0x764/0x800 net/ipv4/tcp.c:1562 tcp_recvmsg+0x334d/0x4ff0 net/ipv4/tcp.c:2166 inet_recvmsg+0x237/0x7d0 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_read_iter+0x5be/0x660 net/socket.c:967 call_read_iter include/linux/fs.h:1864 [inline] new_sync_read fs/read_write.c:414 [inline] __vfs_read+0xa67/0xc90 fs/read_write.c:427 vfs_read+0x359/0x6f0 fs/read_write.c:461 ksys_read+0x265/0x430 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read+0x92/0xb0 fs/read_write.c:595 __x64_sys_read+0x4a/0x70 fs/read_write.c:595 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:187 [inline] kmsan_internal_poison_shadow+0x53/0xa0 mm/kmsan/kmsan.c:146 kmsan_slab_free+0x8d/0x100 mm/kmsan/kmsan_hooks.c:195 slab_free_freelist_hook mm/slub.c:1472 [inline] slab_free mm/slub.c:3038 [inline] kmem_cache_free_bulk+0x3ad9/0x3f50 mm/slub.c:3163 __kfree_skb_flush+0xb0/0x100 net/core/skbuff.c:862 net_rx_action+0x1908/0x1950 net/core/dev.c:6436 __do_softirq+0x4a1/0x83a kernel/softirq.c:293 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1091 do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 ipt_do_table+0x2806/0x28e0 net/ipv4/netfilter/ip_tables.c:358 iptable_raw_hook+0xb5/0xe0 net/ipv4/netfilter/iptable_raw.c:44 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0x18b/0x3f0 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:260 [inline] __ip_local_out+0x69b/0x800 net/ipv4/ip_output.c:114 ip_local_out net/ipv4/ip_output.c:123 [inline] __ip_queue_xmit+0x1bdc/0x21f0 net/ipv4/ip_output.c:532 ip_queue_xmit+0xcc/0xf0 include/net/ip.h:236 __tcp_transmit_skb+0x409e/0x5c60 net/ipv4/tcp_output.c:1158 __tcp_send_ack+0x701/0x840 net/ipv4/tcp_output.c:3681 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3687 tcp_cleanup_rbuf+0x764/0x800 net/ipv4/tcp.c:1562 tcp_recvmsg+0x334d/0x4ff0 net/ipv4/tcp.c:2166 inet_recvmsg+0x237/0x7d0 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_read_iter+0x5be/0x660 net/socket.c:967 call_read_iter include/linux/fs.h:1864 [inline] new_sync_read fs/read_write.c:414 [inline] __vfs_read+0xa67/0xc90 fs/read_write.c:427 vfs_read+0x359/0x6f0 fs/read_write.c:461 ksys_read+0x265/0x430 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read+0x92/0xb0 fs/read_write.c:595 __x64_sys_read+0x4a/0x70 fs/read_write.c:595 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================