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: 0 UID: 0 PID: 22678 Comm: syz.1.4551 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP 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 : [<81415e2c>] lr : [<81415e18>] psr: 60000013 sp : ea949cb0 ip : ea949cb0 fp : ea949ccc r10: 00000001 r9 : 00000084 r8 : ea949d9c r7 : 00004fa7 r6 : 0000009b r5 : 844bc540 r4 : 00004faa r3 : 0000009b r2 : fee04faa r1 : 00000001 r0 : 844bc540 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84d01380 DAC: fffffffd Register r0 information: slab kmalloc-192 start 844bc540 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 844bc540 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 0xea948000 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 0xea948000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xea948000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.1.4551 (pid: 22678, stack limit = 0xea948000) Stack: (0xea949cb0 to 0xea94a000) 9ca0: 81415dcc 844bc540 00004fa7 00004fa7 9cc0: ea949cec ea949cd0 81415b04 81415dd8 00004fa7 8051507c 8546e000 8546e000 9ce0: ea949d0c ea949cf0 81415ec4 81415ab8 844bc540 00000000 8546e000 00004fa7 9d00: ea949d4c ea949d10 81416070 81415e44 8280cc60 840d2080 828217b0 00000000 9d20: 00000000 829d46a0 844bc540 844bc584 ea949d88 844bc540 00000000 82b28ad8 9d40: ea949d84 ea949d50 81404ba4 81416008 844bc570 00000000 ea949d74 200000c0 9d60: 844bc540 b5403587 844bc570 844dbc00 40946400 00000003 ea949e44 ea949d88 9d80: 814004fc 81404aa8 35353238 00000000 00000000 00000000 00000000 00004fa7 9da0: 00000006 00000002 00000007 00000003 00000cc7 7ffffffe 00000002 2f000000 9dc0: 000003ff 00000002 00000300 00000001 00000001 00000009 00007fff 000403fd 9de0: 00000008 000048f3 000001fc 0000008b 0000000a 00400000 20001e54 ffffeadb 9e00: 00000003 00000000 00000008 00000004 07feffff 0000485b 00000000 aa1e06c2 9e20: 00000000 84c59e40 844bc540 200000c0 844bc570 844dbc00 ea949f14 ea949e48 9e40: 814014f0 81400408 00000000 00000000 00000000 00000000 00000000 aa1e06c2 9e60: 00000000 00000000 824a35ec 0000005f 84582250 00000064 845c8a2c 844dbc00 9e80: ea949ee4 ea949e90 807b8030 807ae554 00000064 00000001 00000000 ea949eac 9ea0: 85f5e3d0 834eed48 00006400 0000000b ea949ea0 00000000 00000000 aa1e06c2 9ec0: 84c59e40 40946400 200000c0 200000c0 84c59e40 00000003 ea949ef4 ea949ee8 9ee0: 807b8150 aa1e06c2 ea949f14 40946400 00000000 84c59e41 200000c0 84c59e40 9f00: 00000003 844dbc00 ea949fa4 ea949f18 805856b8 81400f40 ecac8b10 844dbc00 9f20: ea949f3c ea949f30 81aafc8c 81aafb5c ea949f54 ea949f40 8025bcbc 8028e0c4 9f40: ea949fb0 40000000 ea949f84 ea949f58 80221a38 8025bc78 00000000 8281d17c 9f60: ea949fb0 0014c8c0 ecac8b10 8022198c 00000000 aa1e06c2 ea949fac 00000000 9f80: 00000000 00326310 00000036 8020029c 844dbc00 00000036 00000000 ea949fa8 9fa0: 80200060 80585594 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f340bc 9fe0: 76f33ec0 76f33eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81415dcc>] (subdev_8255_io) from [<81415b04>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004fa7 r6:00004fa7 r5:844bc540 r4:81415dcc [<81415aac>] (subdev_8255_do_config) from [<81415ec4>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81415aac>] (subdev_8255_do_config) from [<81415ec4>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8546e000 [<81415e38>] (subdev_8255_io_init) from [<81416070>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81415e38>] (subdev_8255_io_init) from [<81416070>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004fa7 r6:8546e000 r5:00000000 r4:844bc540 [<81415ffc>] (dev_8255_attach) from [<81404ba4>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:844bc540 r7:ea949d88 r6:844bc584 r5:844bc540 r4:829d46a0 [<81404a9c>] (comedi_device_attach) from [<814004fc>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:844dbc00 r7:844bc570 r6:b5403587 r5:844bc540 r4:200000c0 [<814003fc>] (do_devconfig_ioctl) from [<814014f0>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:844dbc00 r7:844bc570 r6:200000c0 r5:844bc540 r4:84c59e40 [<81400f34>] (comedi_unlocked_ioctl) from [<805856b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400f34>] (comedi_unlocked_ioctl) from [<805856b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400f34>] (comedi_unlocked_ioctl) from [<805856b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400f34>] (comedi_unlocked_ioctl) from [<805856b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:844dbc00 r9:00000003 r8:84c59e40 r7:200000c0 r6:84c59e41 r5:00000000 r4:40946400 [<80585588>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea949fa8 to 0xea949ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f340bc 9fe0: 76f33ec0 76f33eb0 000192bc 00132360 r10:00000036 r9:844dbc00 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