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: 0 UID: 0 PID: 12857 Comm: syz.5.1623 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 : [<813b8bd8>] lr : [<813b8bc4>] psr: 60000013 sp : dfc45cb8 ip : dfc45cb8 fp : dfc45cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 83c259c0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 83c259c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8578cf40 DAC: fffffffd Register r0 information: slab kmalloc-192 start 83c259c0 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 83c259c0 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 0xdfc44000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfc44000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.5.1623 (pid: 12857, stack limit = 0xdfc44000) Stack: (0xdfc45cb8 to 0xdfc46000) 5ca0: 813b8b78 83c259c0 5cc0: 00004f27 00004f27 dfc45cf4 dfc45cd8 813b88b0 813b8b84 00004f27 80503b64 5ce0: 85b3e000 85b3e000 dfc45d14 dfc45cf8 813b8c70 813b8864 85b3e000 83c259c0 5d00: dfc45da4 00004f27 dfc45d54 dfc45d18 813b8e64 813b8bf0 82ae3da0 85808280 5d20: 828215b0 00000000 00000000 829d0144 83c259c0 83c25a04 dfc45d90 83c259c0 5d40: 00000000 82b16f40 dfc45d8c dfc45d58 813a7d68 813b8db4 200000c0 00000000 5d60: dfc45d7c 200000c0 83c259c0 b5403587 200000c0 83210c00 40946400 00000003 5d80: dfc45e4c dfc45d90 813a38b4 813a7c6c 35353238 00000000 00000000 00000000 5da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff 5dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 5de0: 0000e1cb 00000008 000000d4 00000003 00000000 00000000 0000d5f2 00000020 5e00: f7fffff5 ffffeadb ffffffff 0000003c 00000008 00000004 08000000 00000009 5e20: 00000000 c6091c4c 00000000 861ca180 83c259c0 200000c0 200000c0 83210c00 5e40: dfc45f14 dfc45e50 813a4880 813a37c0 00000000 00000000 00000000 c6091c4c 5e60: 00000000 00000000 8247054c 0000005f 83dabe58 83c259f0 841b6b94 83210c00 5e80: dfc45ee4 dfc45e90 80797aa4 8078de08 00000064 00000001 00000000 dfc45eac 5ea0: 85bbc790 83434110 00006400 0000000b dfc45ea0 00000000 00000000 c6091c4c 5ec0: 861ca180 40946400 200000c0 200000c0 861ca180 00000003 dfc45ef4 dfc45ee8 5ee0: 80797bc4 c6091c4c dfc45f14 40946400 00000000 861ca181 200000c0 861ca180 5f00: 00000003 83210c00 dfc45fa4 dfc45f18 8056cdc8 813a42b0 ecac8b10 83210c00 5f20: dfc45f3c dfc45f30 81a39df8 81a39cc8 dfc45f54 dfc45f40 8025e490 8028ef6c 5f40: dfc45fb0 40000000 dfc45f84 dfc45f58 802229ec 8025e44c 00000000 8281cddc 5f60: dfc45fb0 0014c820 ecac8b10 80222940 00000000 c6091c4c dfc45fac 00000000 5f80: 00000000 002f6308 00000036 8020029c 83210c00 00000036 00000000 dfc45fa8 5fa0: 80200060 8056cca4 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f800bc 5fe0: 76f7fec0 76f7feb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b8b78>] (subdev_8255_io) from [<813b88b0>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:83c259c0 r4:813b8b78 [<813b8858>] (subdev_8255_do_config) from [<813b8c70>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b8858>] (subdev_8255_do_config) from [<813b8c70>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85b3e000 [<813b8be4>] (subdev_8255_io_init) from [<813b8e64>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b8be4>] (subdev_8255_io_init) from [<813b8e64>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfc45da4 r5:83c259c0 r4:85b3e000 [<813b8da8>] (dev_8255_attach) from [<813a7d68>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b16f40 r9:00000000 r8:83c259c0 r7:dfc45d90 r6:83c25a04 r5:83c259c0 r4:829d0144 [<813a7c60>] (comedi_device_attach) from [<813a38b4>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83210c00 r7:200000c0 r6:b5403587 r5:83c259c0 r4:200000c0 [<813a37b4>] (do_devconfig_ioctl) from [<813a4880>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83210c00 r7:200000c0 r6:200000c0 r5:83c259c0 r4:861ca180 [<813a42a4>] (comedi_unlocked_ioctl) from [<8056cdc8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a42a4>] (comedi_unlocked_ioctl) from [<8056cdc8>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a42a4>] (comedi_unlocked_ioctl) from [<8056cdc8>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a42a4>] (comedi_unlocked_ioctl) from [<8056cdc8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:83210c00 r9:00000003 r8:861ca180 r7:200000c0 r6:861ca181 r5:00000000 r4:40946400 [<8056cc98>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfc45fa8 to 0xdfc45ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f800bc 5fe0: 76f7fec0 76f7feb0 0001948c 001322c0 r10:00000036 r9:83210c00 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