===================================================== BUG: KMSAN: uninit-value in kmsan_check_memory+0xd/0x10 mm/kmsan/kmsan_hooks.c:413 CPU: 1 PID: 19208 Comm: syz-executor.0 Not tainted 5.6.0-rc2-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+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118 kmsan_internal_check_memory+0x358/0x3d0 mm/kmsan/kmsan.c:457 kmsan_check_memory+0xd/0x10 mm/kmsan/kmsan_hooks.c:413 snapshot_compat_ioctl+0x559/0x650 kernel/power/user.c:422 __do_compat_sys_ioctl fs/ioctl.c:857 [inline] __se_compat_sys_ioctl+0x57c/0xed0 fs/ioctl.c:808 __ia32_compat_sys_ioctl+0xd9/0x110 fs/ioctl.c:808 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline] do_fast_syscall_32+0x3c7/0x6e0 arch/x86/entry/common.c:410 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f8cd99 Code: 90 e8 0b 00 00 00 f3 90 0f ae e8 eb f9 8d 74 26 00 89 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5d870cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080083313 RDX: 0000000000000000 RSI: 0000000000000000 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 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165 snapshot_compat_ioctl+0x5e0/0x650 kernel/power/user.c:422 __do_compat_sys_ioctl fs/ioctl.c:857 [inline] __se_compat_sys_ioctl+0x57c/0xed0 fs/ioctl.c:808 __ia32_compat_sys_ioctl+0xd9/0x110 fs/ioctl.c:808 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline] do_fast_syscall_32+0x3c7/0x6e0 arch/x86/entry/common.c:410 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139 Local variable ----offset@snapshot_compat_ioctl created at: get_current arch/x86/include/asm/current.h:15 [inline] snapshot_compat_ioctl+0x324/0x650 kernel/power/user.c:418 get_current arch/x86/include/asm/current.h:15 [inline] snapshot_compat_ioctl+0x324/0x650 kernel/power/user.c:418 Bytes 0-7 of 8 are uninitialized Memory access of size 8 starts at ffffb48403fbfd30 =====================================================