===================================================== BUG: KMSAN: uninit-value in find_prev_fhdr net/ipv6/netfilter/nf_conntrack_reasm.c:399 [inline] BUG: KMSAN: uninit-value in nf_ct_frag6_gather+0x537/0x35f0 net/ipv6/netfilter/nf_conntrack_reasm.c:454 CPU: 0 PID: 20487 Comm: syz-executor.4 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 find_prev_fhdr net/ipv6/netfilter/nf_conntrack_reasm.c:399 [inline] nf_ct_frag6_gather+0x537/0x35f0 net/ipv6/netfilter/nf_conntrack_reasm.c:454 ipv6_defrag+0x523/0x640 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:66 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0x16e/0x400 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:262 [inline] __ip6_local_out+0x56d/0x750 net/ipv6/output_core.c:167 ip6_local_out+0xa4/0x1d0 net/ipv6/output_core.c:177 ip6_send_skb net/ipv6/ip6_output.c:1865 [inline] ip6_push_pending_frames+0x213/0x4f0 net/ipv6/ip6_output.c:1885 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline] rawv6_sendmsg+0x4233/0x5c30 net/ipv6/raw.c:956 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:814 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] kernel_sendmsg+0x384/0x440 net/socket.c:692 sock_no_sendpage+0x235/0x300 net/core/sock.c:2853 kernel_sendpage net/socket.c:3642 [inline] sock_sendpage+0x1e1/0x2c0 net/socket.c:945 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:448 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x565/0xf00 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:834 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x1fd/0x580 fs/splice.c:1016 splice_direct_to_actor+0x6b2/0xf50 fs/splice.c:971 do_splice_direct+0x342/0x580 fs/splice.c:1059 do_sendfile+0x101b/0x1d40 fs/read_write.c:1540 __do_compat_sys_sendfile fs/read_write.c:1622 [inline] __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1605 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1605 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7faf549 Code: Bad RIP value. RSP: 002b:00000000f5daa0cc EFLAGS: 00000296 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000005 RDX: 0000000000000000 RSI: 000000000000edc0 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 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116 skb_copy_from_linear_data_offset include/linux/skbuff.h:3636 [inline] skb_copy_bits+0x217/0xdd0 net/core/skbuff.c:2200 find_prev_fhdr net/ipv6/netfilter/nf_conntrack_reasm.c:414 [inline] nf_ct_frag6_gather+0x3b3/0x35f0 net/ipv6/netfilter/nf_conntrack_reasm.c:454 ipv6_defrag+0x523/0x640 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:66 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0x16e/0x400 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:262 [inline] __ip6_local_out+0x56d/0x750 net/ipv6/output_core.c:167 ip6_local_out+0xa4/0x1d0 net/ipv6/output_core.c:177 ip6_send_skb net/ipv6/ip6_output.c:1865 [inline] ip6_push_pending_frames+0x213/0x4f0 net/ipv6/ip6_output.c:1885 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline] rawv6_sendmsg+0x4233/0x5c30 net/ipv6/raw.c:956 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:814 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] kernel_sendmsg+0x384/0x440 net/socket.c:692 sock_no_sendpage+0x235/0x300 net/core/sock.c:2853 kernel_sendpage net/socket.c:3642 [inline] sock_sendpage+0x1e1/0x2c0 net/socket.c:945 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:448 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x565/0xf00 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:834 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x1fd/0x580 fs/splice.c:1016 splice_direct_to_actor+0x6b2/0xf50 fs/splice.c:971 do_splice_direct+0x342/0x580 fs/splice.c:1059 do_sendfile+0x101b/0x1d40 fs/read_write.c:1540 __do_compat_sys_sendfile fs/read_write.c:1622 [inline] __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1605 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1605 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c 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 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116 csum_partial_copy+0xae/0x100 lib/checksum.c:154 csum_and_memcpy lib/iov_iter.c:586 [inline] csum_and_copy_from_iter_full+0xdca/0x1800 lib/iov_iter.c:1495 ip_generic_getfrag+0x1fb/0x3c0 net/ipv4/ip_output.c:932 raw6_getfrag+0x552/0x600 net/ipv6/raw.c:763 __ip6_append_data+0x507b/0x6320 net/ipv6/ip6_output.c:1623 ip6_append_data+0x3cb/0x660 net/ipv6/ip6_output.c:1757 rawv6_sendmsg+0x32bb/0x5c30 net/ipv6/raw.c:949 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:814 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] kernel_sendmsg+0x384/0x440 net/socket.c:692 sock_no_sendpage+0x235/0x300 net/core/sock.c:2853 kernel_sendpage net/socket.c:3642 [inline] sock_sendpage+0x1e1/0x2c0 net/socket.c:945 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:448 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x565/0xf00 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:834 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x1fd/0x580 fs/splice.c:1016 splice_direct_to_actor+0x6b2/0xf50 fs/splice.c:971 do_splice_direct+0x342/0x580 fs/splice.c:1059 do_sendfile+0x101b/0x1d40 fs/read_write.c:1540 __do_compat_sys_sendfile fs/read_write.c:1622 [inline] __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1605 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1605 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Uninit was created at: kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:269 [inline] kmsan_alloc_page+0xb9/0x180 mm/kmsan/kmsan_shadow.c:293 __alloc_pages_nodemask+0x56a2/0x5dc0 mm/page_alloc.c:4889 alloc_pages_current+0x672/0x990 mm/mempolicy.c:2292 alloc_pages include/linux/gfp.h:545 [inline] push_pipe+0x605/0xb70 lib/iov_iter.c:537 __pipe_get_pages lib/iov_iter.c:1278 [inline] pipe_get_pages_alloc lib/iov_iter.c:1385 [inline] iov_iter_get_pages_alloc+0x18a9/0x21c0 lib/iov_iter.c:1403 default_file_splice_read fs/splice.c:385 [inline] do_splice_to+0x4fc/0x14f0 fs/splice.c:871 splice_direct_to_actor+0x45c/0xf50 fs/splice.c:950 do_splice_direct+0x342/0x580 fs/splice.c:1059 do_sendfile+0x101b/0x1d40 fs/read_write.c:1540 __do_compat_sys_sendfile fs/read_write.c:1622 [inline] __se_compat_sys_sendfile+0x301/0x3c0 fs/read_write.c:1605 __ia32_compat_sys_sendfile+0x56/0x70 fs/read_write.c:1605 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================