8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f23 when write [fee04f23] *pgd=80000080007003 , *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 6941 Comm: syz.2.792 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] PC is at parport_attach+0x174/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] LR is at parport_attach+0x164/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<81401184>] lr : [<81401174>] psr: 60000013 sp : e0131d30 ip : e0131d30 fp : e0131d54 r10: 82b28b30 r9 : 00000003 r8 : 844d8d80 r7 : e0131d90 r6 : 844d8d80 r5 : 00000000 r4 : 00000000 r3 : fee04f23 r2 : 81e24f44 r1 : 00000001 r0 : 81400df4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86778940 DAC: 00000000 Register r0 information: non-slab/vmalloc memory Register r1 information: non-paged memory Register r2 information: non-slab/vmalloc memory Register r3 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 844d8d80 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xe0130000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 844d8d80 pointer offset 0 size 192 Register r9 information: non-paged memory Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xe0130000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xe0130000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Process syz.2.792 (pid: 6941, stack limit = 0xe0130000) Stack: (0xe0131d30 to 0xe0132000) 1d20: 8243d0ec 844d8d80 829d3948 829d3948 1d40: 81e25404 00000000 e0131d8c e0131d58 813fcdb0 8140101c 40946400 00000000 1d60: e0131d7c 200000c0 844d8d80 b5403587 40946400 84dfe000 00000003 844d8db0 1d80: e0131e4c e0131d90 813f86e0 813fccb0 656d6f63 705f6964 6f707261 00007472 1da0: 00000000 00004f23 00000005 00000002 04000401 00000001 40000cc7 00000fff 1dc0: 5c952399 00000005 000003ff 00000802 00000008 00010001 00000001 00000009 1de0: 0000e1cb 00000006 00000401 00000003 00000395 80000089 fffffffd 00000032 1e00: fffffff5 ffffeadb 00000007 0000003c 00000008 00000003 08000000 00002ec0 1e20: 00000000 fd014842 00000000 84d14240 844d8d80 200000c0 40946400 84dfe000 1e40: e0131f14 e0131e50 813f9260 813f8618 00000000 fd014842 00000000 00000000 1e60: 824b15ec e0131ea4 0000005f 8462e640 00000064 84668954 e0131ee4 e0131e88 1e80: 807b404c 807aa6c8 00000064 00000001 00000000 e0131ea4 85f33a90 834e9770 1ea0: 00006400 0000000b e0131e98 00000000 00000000 fd014842 00000000 84d14240 1ec0: 40946400 200000c0 200000c0 84d14240 00000003 84dfe000 e0131ef4 e0131ee8 1ee0: 807b417c fd014842 e0131f14 00000000 84d14241 40946400 200000c0 84d14240 1f00: 00000003 84dfe000 e0131fa4 e0131f18 8058223c 813f9168 ecac8b10 84dfe000 1f20: e0131f3c e0131f30 81aa6c38 81aa6b08 e0131f54 e0131f40 8025ba7c 8028ef68 1f40: e0131fb0 40000000 e0131f84 e0131f58 80221a54 8025ba38 00000000 8281cf7c 1f60: e0131fb0 0013ddc0 ecac8b10 802219a8 00000000 fd014842 e0131fac 00000000 1f80: 00000000 00346310 00000036 8020029c 84dfe000 00000036 00000000 e0131fa8 1fa0: 80200060 80582004 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f820dc 1fe0: 76f81e88 76f81e78 00018734 0012fc20 60000010 00000003 00000000 00000000 Call trace: [<81401010>] (parport_attach) from [<813fcdb0>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r6:00000000 r5:81e25404 r4:829d3948 [<813fcca4>] (comedi_device_attach) from [<813f86e0>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:844d8db0 r9:00000003 r8:84dfe000 r7:40946400 r6:b5403587 r5:844d8d80 r4:200000c0 [<813f860c>] (do_devconfig_ioctl) from [<813f9260>] (comedi_unlocked_ioctl+0x104/0x1c88 drivers/comedi/comedi_fops.c:2240) r8:84dfe000 r7:40946400 r6:200000c0 r5:844d8d80 r4:84d14240 [<813f915c>] (comedi_unlocked_ioctl) from [<8058223c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813f915c>] (comedi_unlocked_ioctl) from [<8058223c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813f915c>] (comedi_unlocked_ioctl) from [<8058223c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813f915c>] (comedi_unlocked_ioctl) from [<8058223c>] (sys_ioctl+0x244/0xb58 fs/ioctl.c:583) r10:84dfe000 r9:00000003 r8:84d14240 r7:200000c0 r6:40946400 r5:84d14241 r4:00000000 [<80581ff8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0131fa8 to 0xe0131ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f820dc 1fe0: 76f81e88 76f81e78 00018734 0012fc20 r10:00000036 r9:84dfe000 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e596306c e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e596306c ldr r3, [r6, #108] @ 0x6c 4: e3a04000 mov r4, #0 8: e7f33053 ubfx r3, r3, #0, #20 c: e2433612 sub r3, r3, #18874368 @ 0x1200000 * 10: e5c34000 strb r4, [r3] <-- trapping instruction