syzbot

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BUG: KMSAN: uninit-value in __list_del_entry_valid+0x400/0x410 lib/list_debug.c:54
CPU: 0 PID: 15460 Comm: udevd Not tainted 5.0.0-rc1+ #9
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 __list_del_entry_valid+0x400/0x410 lib/list_debug.c:54
 __list_del_entry include/linux/list.h:117 [inline]
 list_del include/linux/list.h:125 [inline]
 unlink_anon_vmas+0x28e/0xc50 mm/rmap.c:401
 free_pgtables+0x2e2/0x6a0 mm/memory.c:394
 exit_mmap+0x53f/0xa00 mm/mmap.c:3141
 __mmput+0x159/0x5f0 kernel/fork.c:1048
 mmput+0xb9/0x110 kernel/fork.c:1069
 exec_mmap fs/exec.c:1046 [inline]
 flush_old_exec+0xdea/0x21b0 fs/exec.c:1279
 load_elf_binary+0x10a3/0x85b0 fs/binfmt_elf.c:869
 search_binary_handler+0x2db/0xab0 fs/exec.c:1656
 exec_binprm fs/exec.c:1698 [inline]
 __do_execve_file+0x2440/0x3010 fs/exec.c:1818
 do_execveat_common fs/exec.c:1865 [inline]
 do_execve fs/exec.c:1882 [inline]
 __do_sys_execve fs/exec.c:1963 [inline]
 __se_sys_execve+0xec/0x110 fs/exec.c:1958
 __x64_sys_execve+0x4a/0x70 fs/exec.c:1958
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x7fe9a353d207
Code: Bad RIP value.
RSP: 002b:00007ffc78ce22b8 EFLAGS: 00000206 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fe9a353d207
RDX: 00000000007e69e0 RSI: 00007ffc78ce23b0 RDI: 00007ffc78ce33c0
RBP: 0000000000625500 R08: 00000000000035ce R09: 00000000000035ce
R10: 0000000000000000 R11: 0000000000000206 R12: 00000000007e69e0
R13: 0000000000000007 R14: 00000000007d5250 R15: 0000000000000005

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmem_cache_alloc+0x585/0xb60 mm/slub.c:2772
 anon_vma_chain_alloc mm/rmap.c:130 [inline]
 anon_vma_clone+0x168/0xcb0 mm/rmap.c:270
 anon_vma_fork+0x112/0xbb0 mm/rmap.c:333
 dup_mmap kernel/fork.c:541 [inline]
 dup_mm kernel/fork.c:1321 [inline]
 copy_mm kernel/fork.c:1376 [inline]
 copy_process+0x66f7/0xafe0 kernel/fork.c:1920
 _do_fork+0x384/0x1050 kernel/fork.c:2219
 __do_sys_clone kernel/fork.c:2326 [inline]
 __se_sys_clone+0xf6/0x110 kernel/fork.c:2320
 __x64_sys_clone+0x62/0x80 kernel/fork.c:2320
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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