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BUG: KMSAN: uninit-value in load_script+0x3ae/0xcd0 fs/binfmt_script.c:24
CPU: 0 PID: 3581 Comm: syzkaller208553 Not tainted 4.16.0+ #82
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 load_script+0x3ae/0xcd0 fs/binfmt_script.c:24
 search_binary_handler+0x2ef/0xac0 fs/exec.c:1638
 exec_binprm fs/exec.c:1680 [inline]
 do_execveat_common+0x1f4d/0x2ce0 fs/exec.c:1802
 do_execveat fs/exec.c:1858 [inline]
 SYSC_execveat+0x149/0x170 fs/exec.c:1939
 SyS_execveat+0x76/0xa0 fs/exec.c:1931
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43fd09
RSP: 002b:00007fff0d147b28 EFLAGS: 00000217 ORIG_RAX: 0000000000000142
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd09
RDX: 00000000200f9000 RSI: 0000000020006000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000001000 R09: 00000000004002c8
R10: 0000000020006000 R11: 0000000000000217 R12: 0000000000401630
R13: 00000000004016c0 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:526
 __msan_memcpy+0x19f/0x1f0 mm/kmsan/kmsan_instr.c:470
 _copy_to_iter+0xea2/0x28f0 lib/iov_iter.c:571
 copy_to_iter include/linux/uio.h:106 [inline]
 copy_page_to_iter+0x383/0x1b70 lib/iov_iter.c:712
 shmem_file_read_iter+0x99f/0x1180 mm/shmem.c:2507
 call_read_iter include/linux/fs.h:1776 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 __vfs_read+0x6fb/0x8e0 fs/read_write.c:413
 vfs_read+0x36c/0x6c0 fs/read_write.c:447
 kernel_read+0x11f/0x1a0 fs/read_write.c:426
 prepare_binprm+0x982/0xad0 fs/exec.c:1566
 do_execveat_common+0x1b35/0x2ce0 fs/exec.c:1783
 do_execveat fs/exec.c:1858 [inline]
 SYSC_execveat+0x149/0x170 fs/exec.c:1939
 SyS_execveat+0x76/0xa0 fs/exec.c:1931
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_alloc_meta_for_pages+0x161/0x3a0 mm/kmsan/kmsan.c:814
 kmsan_alloc_page+0x82/0xe0 mm/kmsan/kmsan.c:868
 __alloc_pages_nodemask+0xf5b/0x5dc0 mm/page_alloc.c:4283
 alloc_pages_vma+0xcc8/0x1800 mm/mempolicy.c:2019
 shmem_alloc_page mm/shmem.c:1471 [inline]
 shmem_alloc_and_acct_page+0x6d5/0x1000 mm/shmem.c:1496
 shmem_getpage_gfp+0x35db/0x5770 mm/shmem.c:1771
 shmem_getpage mm/shmem.c:131 [inline]
 shmem_file_read_iter+0x508/0x1180 mm/shmem.c:2456
 call_read_iter include/linux/fs.h:1776 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 __vfs_read+0x6fb/0x8e0 fs/read_write.c:413
 vfs_read+0x36c/0x6c0 fs/read_write.c:447
 kernel_read+0x11f/0x1a0 fs/read_write.c:426
 prepare_binprm+0x982/0xad0 fs/exec.c:1566
 do_execveat_common+0x1b35/0x2ce0 fs/exec.c:1783
 do_execveat fs/exec.c:1858 [inline]
 SYSC_execveat+0x149/0x170 fs/exec.c:1939
 SyS_execveat+0x76/0xa0 fs/exec.c:1931
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
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