8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2b when write [fee04f2b] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 4400 Comm: syz.1.220 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 : [<81436b38>] lr : [<81436b24>] psr: 60000013 sp : df9b5cb8 ip : df9b5cb8 fp : df9b5cd4 r10: 00000000 r9 : 00000084 r8 : df9b5da4 r7 : 00004f28 r6 : 0000009b r5 : 8301aa80 r4 : 00004f2b r3 : 0000009b r2 : fee04f2b r1 : 00000001 r0 : 8301aa80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85ecda80 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8301aa80 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 8301aa80 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xdf9b4000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdf9b4000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdf9b4000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.1.220 (pid: 4400, stack limit = 0xdf9b4000) Stack: (0xdf9b5cb8 to 0xdf9b6000) 5ca0: 81436ad8 00004f28 5cc0: 8301aa80 00004f28 df9b5cf4 df9b5cd8 81436814 81436ae4 00004f28 805223ec 5ce0: 850c9000 850c9000 df9b5d14 df9b5cf8 81436bcc 814367c8 8301aa80 00000000 5d00: 850c9000 00004f28 df9b5d54 df9b5d18 81436d7c 81436b50 df9b5d6c 83372d80 5d20: 82821780 00000000 00000000 829d6504 8301aa80 00000000 df9b5d90 8301aa80 5d40: 00000000 82b2df9c df9b5d8c df9b5d58 81425768 81436d14 40946400 00000000 5d60: df9b5d7c 200000c0 8301aa80 b5403587 40946400 84e74800 00000003 8301aab0 5d80: df9b5e4c df9b5d90 814210a0 81425668 35353238 00000000 00000000 00000000 5da0: 00000000 00004f28 00000005 00006b7b 00000401 fffffc1d 00000cc6 00000ff7 5dc0: 5c952398 00000001 80000000 00000006 00001600 00000007 00000001 fffffffa 5de0: 0000e1cb 00000004 00000004 00080000 00000399 8000008b fffffffe 0000000c 5e00: fffffffe 00000004 00000002 00000039 00000000 02000004 00000002 dffffffa 5e20: 00000000 cc999b34 00000000 85e1b180 8301aa80 200000c0 40946400 84e74800 5e40: df9b5f14 df9b5e50 81421c20 81420fd8 df9b5e4c cc999b34 00000000 00000000 5e60: 824b557c df9b5ea4 0000005f 8429e640 00000064 844e6d8c df9b5ee4 df9b5e88 5e80: 807cb7cc 807c1ba4 00000064 00000001 00000000 df9b5ea4 8385c550 8343d088 5ea0: 00006400 0000000b df9b5e98 00000000 df9b5d38 cc999b34 00000001 85e1b180 5ec0: 40946400 200000c0 200000c0 85e1b180 00000003 84e74800 df9b5ef4 df9b5ee8 5ee0: 807cb8fc cc999b34 df9b5f14 00000000 85e1b181 40946400 200000c0 85e1b180 5f00: 00000003 84e74800 df9b5fa4 df9b5f18 8058f558 81421b28 ecac8b10 84e74800 5f20: df9b5f3c df9b5f30 81ad9c34 81ad9b00 df9b5f54 df9b5f40 8025a85c 8028bff0 5f40: df9b5fb0 40000000 df9b5f84 df9b5f58 80220bf8 8025a818 00000000 8281d27c 5f60: df9b5fb0 0013ddc0 ecac8b10 80220b4c 00000000 cc999b34 df9b5fac 00000000 5f80: 00000000 00346310 00000036 8020029c 84e74800 00000036 00000000 df9b5fa8 5fa0: 80200060 8058f320 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f480dc 5fe0: 76f47e88 76f47e78 00018734 0012fc20 60000010 00000003 00000000 00000000 Call trace: [<81436ad8>] (subdev_8255_io) from [<81436814>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f28 r6:8301aa80 r5:00004f28 r4:81436ad8 [<814367bc>] (subdev_8255_do_config) from [<81436bcc>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814367bc>] (subdev_8255_do_config) from [<81436bcc>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:850c9000 [<81436b44>] (subdev_8255_io_init) from [<81436d7c>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81436b44>] (subdev_8255_io_init) from [<81436d7c>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f28 r6:850c9000 r5:00000000 r4:8301aa80 [<81436d08>] (dev_8255_attach) from [<81425768>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2df9c r9:00000000 r8:8301aa80 r7:df9b5d90 r6:00000000 r5:8301aa80 r4:829d6504 [<8142565c>] (comedi_device_attach) from [<814210a0>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:8301aab0 r9:00000003 r8:84e74800 r7:40946400 r6:b5403587 r5:8301aa80 r4:200000c0 [<81420fcc>] (do_devconfig_ioctl) from [<81421c20>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:84e74800 r7:40946400 r6:200000c0 r5:8301aa80 r4:85e1b180 [<81421b1c>] (comedi_unlocked_ioctl) from [<8058f558>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81421b1c>] (comedi_unlocked_ioctl) from [<8058f558>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81421b1c>] (comedi_unlocked_ioctl) from [<8058f558>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81421b1c>] (comedi_unlocked_ioctl) from [<8058f558>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:84e74800 r9:00000003 r8:85e1b180 r7:200000c0 r6:40946400 r5:85e1b181 r4:00000000 [<8058f314>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9b5fa8 to 0xdf9b5ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f480dc 5fe0: 76f47e88 76f47e78 00018734 0012fc20 r10:00000036 r9:84e74800 r8:8020029c r7:00000036 r6:00346310 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