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: 4058 Comm: syz.1.92 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 : [<813b88b0>] lr : [<813b889c>] psr: 60000013 sp : dfb45cb8 ip : dfb45cb8 fp : dfb45cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 841b6d80 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 841b6d80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85b69480 DAC: 00000000 Register r0 information: slab kmalloc-192 start 841b6d80 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 841b6d80 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 0xdfb44000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfb44000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.1.92 (pid: 4058, stack limit = 0xdfb44000) Stack: (0xdfb45cb8 to 0xdfb46000) 5ca0: 813b8850 841b6d80 5cc0: 00004f27 00004f27 dfb45cf4 dfb45cd8 813b8588 813b885c 00004f27 80503b04 5ce0: 85ba3000 85ba3000 dfb45d14 dfb45cf8 813b8948 813b853c 85ba3000 841b6d80 5d00: dfb45da4 00004f27 dfb45d54 dfb45d18 813b8b3c 813b88c8 82ae3da0 83bea780 5d20: 828215b0 00000000 00000000 829d0104 841b6d80 841b6dc4 dfb45d90 841b6d80 5d40: 00000000 82b16f40 dfb45d8c dfb45d58 813a7a40 813b8a8c 200000c0 00000000 5d60: dfb45d7c 200000c0 841b6d80 b5403587 200000c0 84e38000 40946400 00000003 5d80: dfb45e4c dfb45d90 813a35c0 813a7944 35353238 00000000 00000000 00000000 5da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff 5dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 5de0: 0000e1cb 00000006 00000004 00000003 00000395 80000089 fffffffd 00000000 5e00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 08000000 dffffffa 5e20: 00000000 19b4e7f2 00000000 84883300 841b6d80 200000c0 200000c0 84e38000 5e40: dfb45f14 dfb45e50 813a458c 813a34cc 00000000 00000000 00000000 19b4e7f2 5e60: 00000000 00000000 8247054c 0000005f 8423cc58 841b6db0 841e78c4 84e38000 5e80: dfb45ee4 dfb45e90 80797a24 8078dd88 00000064 00000001 00000000 dfb45eac 5ea0: 858070d0 834efd48 00006400 0000000b dfb45ea0 00000000 00000000 19b4e7f2 5ec0: 84883300 40946400 200000c0 200000c0 84883300 00000003 dfb45ef4 dfb45ee8 5ee0: 80797b44 19b4e7f2 dfb45f14 40946400 00000000 84883301 200000c0 84883300 5f00: 00000003 84e38000 dfb45fa4 dfb45f18 8056cd68 813a3fbc ecac8b10 84e38000 5f20: dfb45f3c dfb45f30 81a39ab8 81a39988 dfb45f54 dfb45f40 8025e490 8028ef64 5f40: dfb45fb0 40000000 dfb45f84 dfb45f58 802229ec 8025e44c 00000000 8281cddc 5f60: dfb45fb0 0014c820 ecac8b10 80222940 00000000 19b4e7f2 dfb45fac 00000000 5f80: 00000000 002f6308 00000036 8020029c 84e38000 00000036 00000000 dfb45fa8 5fa0: 80200060 8056cc44 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fa00bc 5fe0: 76f9fec0 76f9feb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b8850>] (subdev_8255_io) from [<813b8588>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:841b6d80 r4:813b8850 [<813b8530>] (subdev_8255_do_config) from [<813b8948>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b8530>] (subdev_8255_do_config) from [<813b8948>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85ba3000 [<813b88bc>] (subdev_8255_io_init) from [<813b8b3c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b88bc>] (subdev_8255_io_init) from [<813b8b3c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfb45da4 r5:841b6d80 r4:85ba3000 [<813b8a80>] (dev_8255_attach) from [<813a7a40>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r10:82b16f40 r9:00000000 r8:841b6d80 r7:dfb45d90 r6:841b6dc4 r5:841b6d80 r4:829d0104 [<813a7938>] (comedi_device_attach) from [<813a35c0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:84e38000 r7:200000c0 r6:b5403587 r5:841b6d80 r4:200000c0 [<813a34c0>] (do_devconfig_ioctl) from [<813a458c>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:84e38000 r7:200000c0 r6:200000c0 r5:841b6d80 r4:84883300 [<813a3fb0>] (comedi_unlocked_ioctl) from [<8056cd68>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a3fb0>] (comedi_unlocked_ioctl) from [<8056cd68>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a3fb0>] (comedi_unlocked_ioctl) from [<8056cd68>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a3fb0>] (comedi_unlocked_ioctl) from [<8056cd68>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:84e38000 r9:00000003 r8:84883300 r7:200000c0 r6:84883301 r5:00000000 r4:40946400 [<8056cc38>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb45fa8 to 0xdfb45ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fa00bc 5fe0: 76f9fec0 76f9feb0 0001948c 001322c0 r10:00000036 r9:84e38000 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