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BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x81/0x90 mm/kmsan/kmsan_hooks.c:253
CPU: 1 PID: 8489 Comm: syz-executor112 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:39
 copy_to_user include/linux/uaccess.h:186 [inline]
 keyctl_dh_compute_kdf security/keys/dh.c:219 [inline]
 __keyctl_dh_compute+0x24ea/0x2fa0 security/keys/dh.c:386
 keyctl_dh_compute+0x234/0x280 security/keys/dh.c:422
 __do_sys_keyctl security/keys/keyctl.c:1973 [inline]
 __se_sys_keyctl+0x1181/0x1fe0 security/keys/keyctl.c:1869
 __x64_sys_keyctl+0x62/0x80 security/keys/keyctl.c:1869
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x440469
Code: Bad RIP value.
RSP: 002b:00007fffa5664a08 EFLAGS: 00000246 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440469
RDX: 0000000020000540 RSI: 0000000020000400 RDI: 0000000000000017
RBP: 00000000006ca018 R08: 0000000020000980 R09: 00000000004002c8
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000401c70
R13: 0000000000401d00 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
 keyctl_dh_compute+0x234/0x280 security/keys/dh.c:422
 __do_sys_keyctl security/keys/keyctl.c:1973 [inline]
 __se_sys_keyctl+0x1181/0x1fe0 security/keys/keyctl.c:1869
 __x64_sys_keyctl+0x62/0x80 security/keys/keyctl.c:1869
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Bytes 0-2 of 3 are uninitialized
Memory access of size 3 starts at ffff88810761ff90
Data copied to user address 0000000020000540
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