8<--- cut here --- Unable to handle kernel paging request at virtual address fee04faa when write [fee04faa] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 3707 Comm: syz.0.1 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 : [<81415ad4>] lr : [<81415ac0>] psr: 60000013 sp : dfd01cb0 ip : dfd01cb0 fp : dfd01ccc r10: 00000001 r9 : 00000084 r8 : dfd01d9c r7 : 00004fa7 r6 : 0000009b r5 : 8463ce40 r4 : 00004faa r3 : 0000009b r2 : fee04faa r1 : 00000001 r0 : 8463ce40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85c76040 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8463ce40 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 8463ce40 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 0xdfd00000 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 0xdfd00000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfd00000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.1 (pid: 3707, stack limit = 0xdfd00000) Stack: (0xdfd01cb0 to 0xdfd02000) 1ca0: 81415a74 8463ce40 00004fa7 00004fa7 1cc0: dfd01cec dfd01cd0 814157ac 81415a80 00004fa7 80514fb4 857d1800 857d1800 1ce0: dfd01d0c dfd01cf0 81415b6c 81415760 8463ce40 00000000 857d1800 00004fa7 1d00: dfd01d4c dfd01d10 81415d18 81415aec 8280cc60 853c1680 828217b0 00000000 1d20: 00000000 829d46a0 8463ce40 8463ce84 dfd01d88 8463ce40 00000000 82b28ad8 1d40: dfd01d84 dfd01d50 81404848 81415cb0 8463ce70 00000000 dfd01d74 200000c0 1d60: 8463ce40 b5403587 8463ce70 8553d400 40946400 00000003 dfd01e44 dfd01d88 1d80: 814001a0 8140474c 35353238 00000000 00000000 00000000 00000000 00004fa7 1da0: 00000009 00000002 10000421 00000003 00000cc7 7ffffffe 00000000 00000005 1dc0: 000003ff 00000008 00000300 00000001 00000001 00000009 00000000 000403fd 1de0: 00000008 000048f3 000001ff 80000089 0000000a 00400000 20001e54 ffffeadb 1e00: 00000003 0000003d 00000008 00000004 07feffff 0000485b 00000000 0fd61a08 1e20: 00000000 84e123c0 8463ce40 200000c0 8463ce70 8553d400 dfd01f14 dfd01e48 1e40: 81401194 814000ac 00000000 00000000 00000000 00000000 00000000 0fd61a08 1e60: 00000000 00000000 824a35ec 0000005f 83fe5de0 00000064 84498c6c 8553d400 1e80: dfd01ee4 dfd01e90 807b7f68 807ae48c 00000064 00000001 00000000 dfd01eac 1ea0: 84e0c6d0 834e0f68 00006400 0000000b dfd01ea0 00000000 00000000 0fd61a08 1ec0: 84e123c0 40946400 200000c0 200000c0 84e123c0 00000003 dfd01ef4 dfd01ee8 1ee0: 807b8088 0fd61a08 dfd01f14 40946400 00000000 84e123c1 200000c0 84e123c0 1f00: 00000003 8553d400 dfd01fa4 dfd01f18 805855f0 81400be4 ecac8b10 8553d400 1f20: dfd01f3c dfd01f30 81aaf80c 81aaf6dc dfd01f54 dfd01f40 8025bcbc 8028e0c4 1f40: dfd01fb0 40000000 dfd01f84 dfd01f58 80221a38 8025bc78 00000000 8281d17c 1f60: dfd01fb0 0014c8c0 ecac8b10 8022198c 00000000 0fd61a08 dfd01fac 00000000 1f80: 00000000 00326310 00000036 8020029c 8553d400 00000036 00000000 dfd01fa8 1fa0: 80200060 805854cc 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f8d0bc 1fe0: 76f8cec0 76f8ceb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81415a74>] (subdev_8255_io) from [<814157ac>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004fa7 r6:00004fa7 r5:8463ce40 r4:81415a74 [<81415754>] (subdev_8255_do_config) from [<81415b6c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81415754>] (subdev_8255_do_config) from [<81415b6c>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:857d1800 [<81415ae0>] (subdev_8255_io_init) from [<81415d18>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81415ae0>] (subdev_8255_io_init) from [<81415d18>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004fa7 r6:857d1800 r5:00000000 r4:8463ce40 [<81415ca4>] (dev_8255_attach) from [<81404848>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:8463ce40 r7:dfd01d88 r6:8463ce84 r5:8463ce40 r4:829d46a0 [<81404740>] (comedi_device_attach) from [<814001a0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:8553d400 r7:8463ce70 r6:b5403587 r5:8463ce40 r4:200000c0 [<814000a0>] (do_devconfig_ioctl) from [<81401194>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:8553d400 r7:8463ce70 r6:200000c0 r5:8463ce40 r4:84e123c0 [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8553d400 r9:00000003 r8:84e123c0 r7:200000c0 r6:84e123c1 r5:00000000 r4:40946400 [<805854c0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfd01fa8 to 0xdfd01ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f8d0bc 1fe0: 76f8cec0 76f8ceb0 000192bc 00132360 r10:00000036 r9:8553d400 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