8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2a when write [fee04f2a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 3836 Comm: syz.0.7 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 subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] PC is at subdev_8255_io+0x60/0x6c drivers/comedi/drivers/comedi_8255.c:43 LR is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] LR is at subdev_8255_io+0x4c/0x6c drivers/comedi/drivers/comedi_8255.c:43 pc : [<813b85a8>] lr : [<813b8594>] psr: 60000013 sp : dfe0dcb8 ip : dfe0dcb8 fp : dfe0dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 84068a80 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 84068a80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85efe600 DAC: 00000000 Register r0 information: slab kmalloc-192 start 84068a80 pointer offset 0 size 192 Register r1 information: non-paged memory Register r2 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 84068a80 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdfe0c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfe0c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.0.7 (pid: 3836, stack limit = 0xdfe0c000) Stack: (0xdfe0dcb8 to 0xdfe0e000) dca0: 813b8548 84068a80 dcc0: 00004f27 00004f27 dfe0dcf4 dfe0dcd8 813b8280 813b8554 00004f27 80503b98 dce0: 85a66000 85a66000 dfe0dd14 dfe0dcf8 813b8640 813b8234 85a66000 84068a80 dd00: dfe0dda4 00004f27 dfe0dd54 dfe0dd18 813b8834 813b85c0 82ae3d60 83ee1600 dd20: 82821598 00000000 00000000 829d00c4 84068a80 84068ac4 dfe0dd90 84068a80 dd40: 00000000 82b16f00 dfe0dd8c dfe0dd58 813a7738 813b8784 200000c0 00000000 dd60: dfe0dd7c 200000c0 84068a80 b5403587 200000c0 85cabc00 40946400 00000003 dd80: dfe0de4c dfe0dd90 813a32b8 813a763c 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff ddc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000000 00000009 dde0: 0000e1cb 00000006 00000004 00000003 00000395 80000089 fffffffd 00000000 de00: 00000006 ffffeadb 00000003 0001003c 00000008 00000004 08000000 00000005 de20: 00000000 a24a262e 00000000 8552d300 84068a80 200000c0 200000c0 85cabc00 de40: dfe0df14 dfe0de50 813a4284 813a31c4 00000000 00000000 00000000 a24a262e de60: 00000000 00000000 8247054c 0000005f 83d7ec58 84068ab0 841a624c 85cabc00 de80: dfe0dee4 dfe0de90 80797a1c 8078dd80 00000064 00000001 00000000 dfe0deac dea0: 85534cd0 834e62a8 00006400 0000000b dfe0dea0 00000000 00000000 a24a262e dec0: 8552d300 40946400 200000c0 200000c0 8552d300 00000004 dfe0def4 dfe0dee8 dee0: 80797b3c a24a262e dfe0df14 40946400 00000000 8552d301 200000c0 8552d300 df00: 00000004 85cabc00 dfe0dfa4 dfe0df18 8056cd60 813a3cb4 ecac8b10 85cabc00 df20: dfe0df3c dfe0df30 81a394f8 81a393c8 dfe0df54 dfe0df40 8025e490 8028ef64 df40: dfe0dfb0 40000000 dfe0df84 dfe0df58 802229ec 8025e44c 00000000 8281cddc df60: dfe0dfb0 0014c820 ecac8b10 80222940 00000000 a24a262e dfe0dfac 00000000 df80: 00000000 002f6308 00000036 8020029c 85cabc00 00000036 00000000 dfe0dfa8 dfa0: 80200060 8056cc3c 00000000 00000000 00000004 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fc10bc dfe0: 76fc0ec0 76fc0eb0 0001948c 001322c0 60000010 00000004 00000000 00000000 Call trace: [<813b8548>] (subdev_8255_io) from [<813b8280>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:84068a80 r4:813b8548 [<813b8228>] (subdev_8255_do_config) from [<813b8640>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b8228>] (subdev_8255_do_config) from [<813b8640>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85a66000 [<813b85b4>] (subdev_8255_io_init) from [<813b8834>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b85b4>] (subdev_8255_io_init) from [<813b8834>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfe0dda4 r5:84068a80 r4:85a66000 [<813b8778>] (dev_8255_attach) from [<813a7738>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r10:82b16f00 r9:00000000 r8:84068a80 r7:dfe0dd90 r6:84068ac4 r5:84068a80 r4:829d00c4 [<813a7630>] (comedi_device_attach) from [<813a32b8>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:85cabc00 r7:200000c0 r6:b5403587 r5:84068a80 r4:200000c0 [<813a31b8>] (do_devconfig_ioctl) from [<813a4284>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:85cabc00 r7:200000c0 r6:200000c0 r5:84068a80 r4:8552d300 [<813a3ca8>] (comedi_unlocked_ioctl) from [<8056cd60>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a3ca8>] (comedi_unlocked_ioctl) from [<8056cd60>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a3ca8>] (comedi_unlocked_ioctl) from [<8056cd60>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a3ca8>] (comedi_unlocked_ioctl) from [<8056cd60>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:85cabc00 r9:00000004 r8:8552d300 r7:200000c0 r6:8552d301 r5:00000000 r4:40946400 [<8056cc30>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfe0dfa8 to 0xdfe0dff0) dfa0: 00000000 00000000 00000004 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fc10bc dfe0: 76fc0ec0 76fc0eb0 0001948c 001322c0 r10:00000036 r9:85cabc00 r8:8020029c r7:00000036 r6:002f6308 r5:00000000 r4:00000000 Code: e6ef3076 e0842002 e7f32052 e2422612 (e5c23000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef3076 uxtb r3, r6 4: e0842002 add r2, r4, r2 8: e7f32052 ubfx r2, r2, #0, #20 c: e2422612 sub r2, r2, #18874368 @ 0x1200000 * 10: e5c23000 strb r3, [r2] <-- trapping instruction