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BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x81/0x90 mm/kmsan/kmsan_hooks.c:253
CPU: 0 PID: 10617 Comm: syz-executor.2 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+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 kmsan_internal_check_memory+0x358/0x3d0 mm/kmsan/kmsan.c:457
 kmsan_copy_to_user+0x81/0x90 mm/kmsan/kmsan_hooks.c:253
 instrument_copy_to_user include/linux/instrumented.h:91 [inline]
 _copy_to_user+0x18e/0x260 lib/usercopy.c:33
 copy_to_user include/linux/uaccess.h:170 [inline]
 keyctl_dh_compute_kdf security/keys/dh.c:219 [inline]
 __keyctl_dh_compute+0x24ea/0x2fa0 security/keys/dh.c:386
 compat_keyctl_dh_compute+0x34b/0x3e0 security/keys/compat_dh.c:35
 __do_compat_sys_keyctl security/keys/compat.c:127 [inline]
 __se_compat_sys_keyctl+0xb35/0xd90 security/keys/compat.c:50
 __ia32_compat_sys_keyctl+0x62/0x80 security/keys/compat.c:50
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2af/0x480 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: 0023:0xf7fd7549
Code: Bad RIP value.
RSP: 002b:00000000f55b00cc EFLAGS: 00000296 ORIG_RAX: 0000000000000120
RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 00000000200000c0
RDX: 0000000020000340 RSI: 000000000000008c RDI: 0000000020000300
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2839 [inline]
 slab_alloc mm/slub.c:2848 [inline]
 __kmalloc+0x312/0x410 mm/slub.c:3911
 kmalloc include/linux/slab.h:560 [inline]
 keyctl_dh_compute_kdf security/keys/dh.c:208 [inline]
 __keyctl_dh_compute+0x1f82/0x2fa0 security/keys/dh.c:386
 compat_keyctl_dh_compute+0x34b/0x3e0 security/keys/compat_dh.c:35
 __do_compat_sys_keyctl security/keys/compat.c:127 [inline]
 __se_compat_sys_keyctl+0xb35/0xd90 security/keys/compat.c:50
 __ia32_compat_sys_keyctl+0x62/0x80 security/keys/compat.c:50
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2af/0x480 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

Bytes 0-139 of 140 are uninitialized
Memory access of size 140 starts at ffff8881d55e16c0
Data copied to user address 0000000020000340
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