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: 4723 Comm: syz.0.228 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 : [<81415c6c>] lr : [<81415c58>] psr: 60000013 sp : dfb51cb0 ip : dfb51cb0 fp : dfb51ccc r10: 00000001 r9 : 00000084 r8 : dfb51d9c r7 : 00004f27 r6 : 0000009b r5 : 8441ecc0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8441ecc0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85ffbb00 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8441ecc0 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 8441ecc0 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 0xdfb50000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfb50000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfb50000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.228 (pid: 4723, stack limit = 0xdfb50000) Stack: (0xdfb51cb0 to 0xdfb52000) 1ca0: 81415c0c 8441ecc0 00004f27 00004f27 1cc0: dfb51cec dfb51cd0 81415944 81415c18 00004f27 80514fcc 8548e000 8548e000 1ce0: dfb51d0c dfb51cf0 81415d04 814158f8 8441ecc0 00000000 8548e000 00004f27 1d00: dfb51d4c dfb51d10 81415eb0 81415c84 8280cc60 85e92600 828217b0 00000000 1d20: 00000000 829d46a0 8441ecc0 8441ed04 dfb51d88 8441ecc0 00000000 82b28ad8 1d40: dfb51d84 dfb51d50 814049e0 81415e48 8441ecf0 00000000 dfb51d74 200000c0 1d60: 8441ecc0 b5403587 8441ecf0 857c1800 40946400 00000003 dfb51e44 dfb51d88 1d80: 81400338 814048e4 35353238 00000000 00000000 00000000 00000000 00004f27 1da0: 00000005 00000022 00000401 00000001 00006dc4 00000fff 5c95239c 00000005 1dc0: 000003ff 00000806 00000401 00000001 00000002 00000009 0000e1cb 00000005 1de0: 00000004 00000003 00000395 8000008b fffffffe 0000000a fffffff5 00000001 1e00: 00000003 00000000 00000000 00000004 08000000 dffffff9 00000000 1652eb18 1e20: 00000000 85f92f00 8441ecc0 200000c0 8441ecf0 857c1800 dfb51f14 dfb51e48 1e40: 8140132c 81400244 00000000 00000000 00000000 00000000 00000000 1652eb18 1e60: 00000000 00000000 824a35ec 0000005f 8410d7f8 00000064 8443dd8c 857c1800 1e80: dfb51ee4 dfb51e90 807b7f80 807ae4a4 00000064 00000001 00000000 dfb51eac 1ea0: 85c8b250 8342daa0 00006400 0000000b dfb51ea0 00000000 00000000 1652eb18 1ec0: 85f92f00 40946400 200000c0 200000c0 85f92f00 00000003 dfb51ef4 dfb51ee8 1ee0: 807b80a0 1652eb18 dfb51f14 40946400 00000000 85f92f01 200000c0 85f92f00 1f00: 00000003 857c1800 dfb51fa4 dfb51f18 80585608 81400d7c ecac8b10 857c1800 1f20: dfb51f3c dfb51f30 81aaf9ac 81aaf87c dfb51f54 dfb51f40 8025bcbc 8028e0c4 1f40: dfb51fb0 40000000 dfb51f84 dfb51f58 80221a38 8025bc78 00000000 8281d17c 1f60: dfb51fb0 0014c8c0 ecac8b10 8022198c 00000000 1652eb18 dfb51fac 00000000 1f80: 00000000 00326310 00000036 8020029c 857c1800 00000036 00000000 dfb51fa8 1fa0: 80200060 805854e4 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fff0bc 1fe0: 76ffeec0 76ffeeb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81415c0c>] (subdev_8255_io) from [<81415944>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8441ecc0 r4:81415c0c [<814158ec>] (subdev_8255_do_config) from [<81415d04>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814158ec>] (subdev_8255_do_config) from [<81415d04>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8548e000 [<81415c78>] (subdev_8255_io_init) from [<81415eb0>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81415c78>] (subdev_8255_io_init) from [<81415eb0>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:8548e000 r5:00000000 r4:8441ecc0 [<81415e3c>] (dev_8255_attach) from [<814049e0>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:8441ecc0 r7:dfb51d88 r6:8441ed04 r5:8441ecc0 r4:829d46a0 [<814048d8>] (comedi_device_attach) from [<81400338>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:857c1800 r7:8441ecf0 r6:b5403587 r5:8441ecc0 r4:200000c0 [<81400238>] (do_devconfig_ioctl) from [<8140132c>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:857c1800 r7:8441ecf0 r6:200000c0 r5:8441ecc0 r4:85f92f00 [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:857c1800 r9:00000003 r8:85f92f00 r7:200000c0 r6:85f92f01 r5:00000000 r4:40946400 [<805854d8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb51fa8 to 0xdfb51ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fff0bc 1fe0: 76ffeec0 76ffeeb0 000192bc 00132360 r10:00000036 r9:857c1800 r8:8020029c r7:00000036 r6:00326310 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