================================================================== BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 CPU: 1 PID: 14806 Comm: syz-executor5 Not tainted 4.20.0-rc7+ #6 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 kmsan_internal_check_memory+0x9e4/0xb10 mm/kmsan/kmsan.c:692 kmsan_copy_to_user+0xab/0xc0 mm/kmsan/kmsan_hooks.c:601 _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 capi_ioctl include/linux/uaccess.h:177 [inline] capi_unlocked_ioctl+0x1a0b/0x1bf0 drivers/isdn/capi/capi.c:939 do_vfs_ioctl+0xebd/0x2bf0 fs/ioctl.c:46 ksys_ioctl fs/ioctl.c:713 [inline] __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fdbe9be4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000020000100 RSI: 00000000c0044306 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdbe9be56d4 R13: 00000000004bf431 R14: 00000000004d0ad8 R15: 00000000ffffffff Local variable description: ----data.i@capi_unlocked_ioctl Variable was created at: capi_ioctl drivers/isdn/capi/capi.c:747 [inline] capi_unlocked_ioctl+0x82/0x1bf0 drivers/isdn/capi/capi.c:939 do_vfs_ioctl+0xebd/0x2bf0 fs/ioctl.c:46 Bytes 12-63 of 64 are uninitialized Memory access of size 64 starts at ffff88809769fce8 Data copied to user address 0000000020000100 ==================================================================