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: 30235 Comm: syz.2.8592 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 : [<813b8858>] lr : [<813b8844>] psr: 60000013 sp : df881cb8 ip : df881cb8 fp : df881cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 83ae9e40 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 83ae9e40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85dba200 DAC: fffffffd Register r0 information: slab kmalloc-192 start 83ae9e40 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 83ae9e40 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 0xdf880000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdf880000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.2.8592 (pid: 30235, stack limit = 0xdf880000) Stack: (0xdf881cb8 to 0xdf882000) 1ca0: 813b87f8 83ae9e40 1cc0: 00004f27 00004f27 df881cf4 df881cd8 813b8530 813b8804 00004f27 df881cf8 1ce0: 00000000 855f0000 df881d14 df881cf8 813b88f0 813b84e4 855f0000 83ae9e40 1d00: df881da4 00004f27 df881d54 df881d18 813b8ae4 813b8870 82ae3da0 83ec0a00 1d20: 828215b0 00000000 00000000 829d0104 83ae9e40 83ae9e84 df881d90 83ae9e40 1d40: 00000000 82b16f40 df881d8c df881d58 813a79e8 813b8a34 200000c0 00000000 1d60: df881d7c 200000c0 83ae9e40 b5403587 200000c0 8584e000 40946400 00000003 1d80: df881e4c df881d90 813a3568 813a78ec 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000002 00000421 00000001 00000cc7 7fffffff 1dc0: 5c952399 00000005 000003ff 00000002 00000300 00000001 00000001 00000009 1de0: 00000000 00000000 00000008 fffffffa 000001ff 80000089 0000000a 00000000 1e00: 20001e54 ffffeadb 00000003 0000003d 00000008 00000004 08000000 dffffffa 1e20: 00000000 9c93c3ad 00000000 84bcacc0 83ae9e40 200000c0 200000c0 8584e000 1e40: df881f14 df881e50 813a4534 813a3474 00000000 00000000 00000000 9c93c3ad 1e60: 00000000 00000000 8247054c 0000005f 840de458 83ae9e70 842cc00c 8584e000 1e80: df881ee4 df881e90 80797a24 8078dd88 00000064 00000001 00000000 df881eac 1ea0: 85ec6850 83416dd0 00006400 0000000b df881ea0 00000000 00000000 9c93c3ad 1ec0: 84bcacc0 40946400 200000c0 200000c0 84bcacc0 00000003 df881ef4 df881ee8 1ee0: 80797b44 9c93c3ad df881f14 40946400 00000000 84bcacc1 200000c0 84bcacc0 1f00: 00000003 8584e000 df881fa4 df881f18 8056cd68 813a3f64 ecac8b10 8584e000 1f20: df881f3c df881f30 81a39a78 81a39948 df881f54 df881f40 8025e490 8028ef64 1f40: df881fb0 40000000 df881f84 df881f58 802229ec 8025e44c 00000000 8281cddc 1f60: df881fb0 0014c820 ecac8b10 80222940 00000000 9c93c3ad df881fac 00000000 1f80: 00000000 002f6308 00000036 8020029c 8584e000 00000036 00000000 df881fa8 1fa0: 80200060 8056cc44 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f780bc 1fe0: 76f77ec0 76f77eb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b87f8>] (subdev_8255_io) from [<813b8530>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:83ae9e40 r4:813b87f8 [<813b84d8>] (subdev_8255_do_config) from [<813b88f0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b84d8>] (subdev_8255_do_config) from [<813b88f0>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:855f0000 [<813b8864>] (subdev_8255_io_init) from [<813b8ae4>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b8864>] (subdev_8255_io_init) from [<813b8ae4>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:df881da4 r5:83ae9e40 r4:855f0000 [<813b8a28>] (dev_8255_attach) from [<813a79e8>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r10:82b16f40 r9:00000000 r8:83ae9e40 r7:df881d90 r6:83ae9e84 r5:83ae9e40 r4:829d0104 [<813a78e0>] (comedi_device_attach) from [<813a3568>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8584e000 r7:200000c0 r6:b5403587 r5:83ae9e40 r4:200000c0 [<813a3468>] (do_devconfig_ioctl) from [<813a4534>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:8584e000 r7:200000c0 r6:200000c0 r5:83ae9e40 r4:84bcacc0 [<813a3f58>] (comedi_unlocked_ioctl) from [<8056cd68>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a3f58>] (comedi_unlocked_ioctl) from [<8056cd68>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a3f58>] (comedi_unlocked_ioctl) from [<8056cd68>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a3f58>] (comedi_unlocked_ioctl) from [<8056cd68>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:8584e000 r9:00000003 r8:84bcacc0 r7:200000c0 r6:84bcacc1 r5:00000000 r4:40946400 [<8056cc38>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf881fa8 to 0xdf881ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f780bc 1fe0: 76f77ec0 76f77eb0 0001948c 001322c0 r10:00000036 r9:8584e000 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