urandom_read: 1 callbacks suppressed random: sshd: uninitialized urandom read (32 bytes read) audit: type=1400 audit(1566023701.227:7): avc: denied { map } for pid=1759 comm="syz-executor758" path="/root/syz-executor758101835" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI Modules linked in: CPU: 0 PID: 1759 Comm: syz-executor758 Not tainted 4.14.139+ #34 task: (ptrval) task.stack: (ptrval) RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:compound_head include/linux/page-flags.h:148 [inline] RIP: 0010:get_page include/linux/mm.h:836 [inline] RIP: 0010:submit_page_section fs/direct-io.c:890 [inline] RIP: 0010:do_direct_IO fs/direct-io.c:1097 [inline] RIP: 0010:do_blockdev_direct_IO fs/direct-io.c:1336 [inline] RIP: 0010:__blockdev_direct_IO+0x1dcf/0xe24e fs/direct-io.c:1422 RSP: 0018:ffff8881d100f330 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffea00073f341c RCX: ffffffffa2c36753 RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000020 RBP: ffff8881d100f668 R08: 0000000000000000 R09: fffff94000e7e684 R10: fffff94000e7e683 R11: ffffea00073f341f R12: ffffea00073f3400 R13: ffffea00073f3400 R14: 0000000000000000 R15: ffff8881d1b08000 FS: 00000000019a0880(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020011000 CR3: 00000001d188c005 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_direct_IO_write fs/ext4/inode.c:3716 [inline] ext4_direct_IO+0xa4f/0x2820 fs/ext4/inode.c:3869 generic_file_direct_write+0x1e4/0x430 mm/filemap.c:3035 __generic_file_write_iter+0x209/0x550 mm/filemap.c:3214 ext4_file_write_iter+0x58f/0xdb0 fs/ext4/file.c:268 call_write_iter include/linux/fs.h:1788 [inline] do_iter_readv_writev+0x379/0x580 fs/read_write.c:679 do_iter_write fs/read_write.c:958 [inline] do_iter_write+0x152/0x550 fs/read_write.c:939 vfs_iter_write+0x70/0xa0 fs/read_write.c:971 iter_file_splice_write+0x560/0xa50 fs/splice.c:749 do_splice_from fs/splice.c:851 [inline] do_splice fs/splice.c:1147 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0xcd6/0x1270 fs/splice.c:1382 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x440319 RSP: 002b:00007ffc49acada8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440319 RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401ba0 R13: 0000000000401c30 R14: 0000000000000000 R15: 0000000000000000 Code: 4c a4 e8 e5 7f e9 ff 0f 0b e8 3e d4 cd ff 48 8b 84 24 e8 00 00 00 48 8d 78 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 37 a0 00 00 48 8b 84 24 e8 00 00 00 4c 8b 60 RIP: __read_once_size include/linux/compiler.h:183 [inline] RSP: ffff8881d100f330 RIP: compound_head include/linux/page-flags.h:148 [inline] RSP: ffff8881d100f330 RIP: get_page include/linux/mm.h:836 [inline] RSP: ffff8881d100f330 RIP: submit_page_section fs/direct-io.c:890 [inline] RSP: ffff8881d100f330 RIP: do_direct_IO fs/direct-io.c:1097 [inline] RSP: ffff8881d100f330 RIP: do_blockdev_direct_IO fs/direct-io.c:1336 [inline] RSP: ffff8881d100f330 RIP: __blockdev_direct_IO+0x1dcf/0xe24e fs/direct-io.c:1422 RSP: ffff8881d100f330 ---[ end trace c4bdc841745cfb7f ]---