8<--- cut here --- Unable to handle kernel paging request at virtual address fee04fa7 when write [fee04fa7] *pgd=80000080007003 , *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 6405 Comm: syz.0.508 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 : [<8140a510>] lr : [<8140a500>] psr: 60000013 sp : dfab1d28 ip : dfab1d28 fp : dfab1d4c r10: 82b28ad8 r9 : 00000003 r8 : 84499a80 r7 : dfab1d88 r6 : 84499a80 r5 : 00000000 r4 : 00000000 r3 : fee04fa7 r2 : 81e1a398 r1 : 00000001 r0 : 8140a180 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85075180 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 84499a80 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfab0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 84499a80 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 0xdfab0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfab0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.508 (pid: 6405, stack limit = 0xdfab0000) Stack: (0xdfab1d28 to 0xdfab2000) 1d20: 82433488 84499a80 829d3f08 829d3f08 81e1a858 84499ac4 1d40: dfab1d84 dfab1d50 814061bc 8140a3a8 84499ab0 00000000 dfab1d74 200000c0 1d60: 84499a80 b5403587 84499ab0 85f32400 40946400 00000003 dfab1e44 dfab1d88 1d80: 81401b14 814060c0 656d6f63 705f6964 6f707261 00007472 00000000 00004fa7 1da0: 00000105 00000002 10000421 02000001 00000cc7 7ffffffe 5c952398 00000005 1dc0: 000003ff 00000002 00000300 00000001 00000001 00000009 00000000 00040400 1de0: 00000008 000048f3 000001ff 80000089 0000000a 00400000 20001e54 ffffeadb 1e00: 00000003 0000003d 00000002 00000004 07ffffff 0000485b 00000000 54b519df 1e20: 00000000 851c7540 84499a80 200000c0 84499ab0 85f32400 dfab1f14 dfab1e48 1e40: 81402b08 81401a20 00000000 00000000 00000000 00000000 00000000 54b519df 1e60: 00000000 00000000 824a45ec 0000005f 845f6250 00000064 8464b0e4 85f32400 1e80: dfab1ee4 dfab1e90 807b8730 807aec54 00000064 00000001 00000000 dfab1eac 1ea0: 85053cd0 834dfd48 00006400 0000000b dfab1ea0 00000000 00000000 54b519df 1ec0: 851c7540 40946400 200000c0 200000c0 851c7540 00000003 dfab1ef4 dfab1ee8 1ee0: 807b8850 54b519df dfab1f14 40946400 00000000 851c7541 200000c0 851c7540 1f00: 00000003 85f32400 dfab1fa4 dfab1f18 80585cc0 81402558 ecac8b10 85f32400 1f20: dfab1f3c dfab1f30 81ab1624 81ab14f4 dfab1f54 dfab1f40 8025bcbc 8028e0c4 1f40: dfab1fb0 40000000 dfab1f84 dfab1f58 80221a38 8025bc78 00000000 8281cf7c 1f60: dfab1fb0 0014c8c0 ecac8b10 8022198c 00000000 54b519df dfab1fac 00000000 1f80: 00000000 00326310 00000036 8020029c 85f32400 00000036 00000000 dfab1fa8 1fa0: 80200060 80585b9c 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f130bc 1fe0: 76f12ec0 76f12eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<8140a39c>] (parport_attach) from [<814061bc>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r6:84499ac4 r5:81e1a858 r4:829d3f08 [<814060b4>] (comedi_device_attach) from [<81401b14>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:85f32400 r7:84499ab0 r6:b5403587 r5:84499a80 r4:200000c0 [<81401a14>] (do_devconfig_ioctl) from [<81402b08>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:85f32400 r7:84499ab0 r6:200000c0 r5:84499a80 r4:851c7540 [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:85f32400 r9:00000003 r8:851c7540 r7:200000c0 r6:851c7541 r5:00000000 r4:40946400 [<80585b90>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfab1fa8 to 0xdfab1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f130bc 1fe0: 76f12ec0 76f12eb0 000192bc 00132360 r10:00000036 r9:85f32400 r8:8020029c r7:00000036 r6:00326310 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