8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f27 when write [fee04f27] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 3920 Comm: syz.0.64 Not tainted syzkaller #0 PREEMPT 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 : [<81408878>] lr : [<81408868>] psr: 60000013 sp : df9f1d28 ip : df9f1d28 fp : df9f1d4c r10: 82b28ad8 r9 : 00000003 r8 : 84517900 r7 : df9f1d88 r6 : 84517900 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e1a338 r1 : 00000001 r0 : 814084e8 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 860c6480 DAC: fffffffd 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 84517900 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf9f0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 84517900 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 0xdf9f0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdf9f0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.64 (pid: 3920, stack limit = 0xdf9f0000) Stack: (0xdf9f1d28 to 0xdf9f2000) 1d20: 82432d94 84517900 829d3f08 829d3f08 81e1a7f8 84517944 1d40: df9f1d84 df9f1d50 81404520 81408710 84517930 00000000 df9f1d74 200000c0 1d60: 84517900 b5403587 84517930 83edc800 40946400 00000003 df9f1e44 df9f1d88 1d80: 813ffe78 81404424 656d6f63 705f6964 6f707261 00007472 00000000 00004f27 1da0: 00005d93 00000008 00000006 00000005 00000005 00000009 00000007 54c6cff3 1dc0: 000000fd 00000002 00008401 00000006 00000005 00000006 00000101 00000000 1de0: 00000892 0000a418 40000001 00000005 0000caa3 00000008 20001e5b 00000000 1e00: 00000e66 00000004 00000008 00000005 00000000 fffffff8 00000000 d32f4ada 1e20: 00000000 8603a600 84517900 200000c0 84517930 83edc800 df9f1f14 df9f1e48 1e40: 81400e6c 813ffd84 00000000 00000000 00000000 00000000 00000000 d32f4ada 1e60: 00000000 00000000 824a35ec 0000005f 8441e448 00000064 844f9cb4 83edc800 1e80: df9f1ee4 df9f1e90 807b7d38 807ae25c 00000064 00000001 00000000 df9f1eac 1ea0: 8608e610 8343aaa0 00006400 0000000b df9f1ea0 00000000 00000000 d32f4ada 1ec0: 8603a600 40946400 200000c0 200000c0 8603a600 00000003 df9f1ef4 df9f1ee8 1ee0: 807b7e58 d32f4ada df9f1f14 40946400 00000000 8603a601 200000c0 8603a600 1f00: 00000003 83edc800 df9f1fa4 df9f1f18 805854f4 814008bc ecac8b10 83edc800 1f20: df9f1f3c df9f1f30 81aaf31c 81aaf1ec df9f1f54 df9f1f40 8025bcbc 8028e07c 1f40: df9f1fb0 40000000 df9f1f84 df9f1f58 80221a38 8025bc78 00000000 8281d17c 1f60: df9f1fb0 0014c880 ecac8b10 8022198c 00000000 d32f4ada df9f1fac 00000000 1f80: 00000000 00316310 00000036 8020029c 83edc800 00000036 00000000 df9f1fa8 1fa0: 80200060 805853d0 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316310 00000036 00300000 00000000 00006364 76f920bc 1fe0: 76f91ec0 76f91eb0 0001929c 00132320 60000010 00000003 00000000 00000000 Call trace: [<81408704>] (parport_attach) from [<81404520>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r6:84517944 r5:81e1a7f8 r4:829d3f08 [<81404418>] (comedi_device_attach) from [<813ffe78>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:83edc800 r7:84517930 r6:b5403587 r5:84517900 r4:200000c0 [<813ffd78>] (do_devconfig_ioctl) from [<81400e6c>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:83edc800 r7:84517930 r6:200000c0 r5:84517900 r4:8603a600 [<814008b0>] (comedi_unlocked_ioctl) from [<805854f4>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814008b0>] (comedi_unlocked_ioctl) from [<805854f4>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814008b0>] (comedi_unlocked_ioctl) from [<805854f4>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814008b0>] (comedi_unlocked_ioctl) from [<805854f4>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83edc800 r9:00000003 r8:8603a600 r7:200000c0 r6:8603a601 r5:00000000 r4:40946400 [<805853c4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9f1fa8 to 0xdf9f1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316310 00000036 00300000 00000000 00006364 76f920bc 1fe0: 76f91ec0 76f91eb0 0001929c 00132320 r10:00000036 r9:83edc800 r8:8020029c r7:00000036 r6:00316310 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