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: 3887 Comm: syz.1.60 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 : df9f1cb8 ip : df9f1cb8 fp : df9f1cd4 r10: 00000000 r9 : 00000084 r8 : df9f1da4 r7 : 00004f27 r6 : 0000009b r5 : 84269900 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 84269900 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85f192c0 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84269900 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 84269900 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 0xdf9f0000 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 0xdf9f0000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdf9f0000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.1.60 (pid: 3887, stack limit = 0xdf9f0000) Stack: (0xdf9f1cb8 to 0xdf9f2000) 1ca0: 81436ad8 00004f27 1cc0: 84269900 00004f27 df9f1cf4 df9f1cd8 81436814 81436ae4 00004f27 805223ec 1ce0: 85b27000 85b27000 df9f1d14 df9f1cf8 81436bcc 814367c8 84269900 00000000 1d00: 85b27000 00004f27 df9f1d54 df9f1d18 81436d7c 81436b50 82b15584 830e3880 1d20: 82821780 00000000 00000000 829d6504 84269900 00000000 df9f1d90 84269900 1d40: 00000000 82b2df9c df9f1d8c df9f1d58 81425768 81436d14 40946400 00000000 1d60: df9f1d7c 200000c0 84269900 b5403587 40946400 83eb3000 00000003 84269930 1d80: df9f1e4c df9f1d90 814210a0 81425668 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000007 00000401 00000001 00000cc7 00000fff 1dc0: 5c952399 00000005 000000da 00000802 00001600 fffffdfd 00000001 00000000 1de0: 0000e1cb 00000006 00000004 00000006 00000395 00000000 fffffffd 00000000 1e00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 08000000 dffffffa 1e20: 00000000 2d44eb22 00000000 851ffe40 84269900 200000c0 40946400 83eb3000 1e40: df9f1f14 df9f1e50 81421c20 81420fd8 00000000 2d44eb22 00000000 00000000 1e60: 824b557c df9f1ea4 0000005f 8448aa30 00000064 844d5444 df9f1ee4 df9f1e88 1e80: 807cb7cc 807c1ba4 00000064 00000001 00000000 df9f1ea4 830cf790 8342e6e8 1ea0: 00006400 0000000b df9f1e98 00000000 00000000 2d44eb22 00000000 851ffe40 1ec0: 40946400 200000c0 200000c0 851ffe40 00000003 83eb3000 df9f1ef4 df9f1ee8 1ee0: 807cb8fc 2d44eb22 df9f1f14 00000000 851ffe41 40946400 200000c0 851ffe40 1f00: 00000003 83eb3000 df9f1fa4 df9f1f18 8058f558 81421b28 ecac8b10 83eb3000 1f20: df9f1f3c df9f1f30 81ad9c34 81ad9b00 df9f1f54 df9f1f40 8025a85c 8028bff0 1f40: df9f1fb0 40000000 df9f1f84 df9f1f58 80220bf8 8025a818 00000000 8281d27c 1f60: df9f1fb0 0013ddc0 ecac8b10 80220b4c 00000000 2d44eb22 df9f1fac 00000000 1f80: 00000000 00346310 00000036 8020029c 83eb3000 00000036 00000000 df9f1fa8 1fa0: 80200060 8058f320 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f440dc 1fe0: 76f43e88 76f43e78 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) r7:00004f27 r6:84269900 r5:00004f27 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) r4:85b27000 [<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) r7:00004f27 r6:85b27000 r5:00000000 r4:84269900 [<81436d08>] (dev_8255_attach) from [<81425768>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2df9c r9:00000000 r8:84269900 r7:df9f1d90 r6:00000000 r5:84269900 r4:829d6504 [<8142565c>] (comedi_device_attach) from [<814210a0>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:84269930 r9:00000003 r8:83eb3000 r7:40946400 r6:b5403587 r5:84269900 r4:200000c0 [<81420fcc>] (do_devconfig_ioctl) from [<81421c20>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:83eb3000 r7:40946400 r6:200000c0 r5:84269900 r4:851ffe40 [<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) r10:83eb3000 r9:00000003 r8:851ffe40 r7:200000c0 r6:40946400 r5:851ffe41 r4:00000000 [<8058f314>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9f1fa8 to 0xdf9f1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f440dc 1fe0: 76f43e88 76f43e78 00018734 0012fc20 r10:00000036 r9:83eb3000 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