8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f27 when write [fee04f27] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 22809 Comm: syz.4.10198 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 parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] PC is at parport_attach+0x174/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] LR is at parport_attach+0x164/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<814339b4>] lr : [<814339a4>] psr: 60000013 sp : df9e9d30 ip : df9e9d30 fp : df9e9d54 r10: 82b2f064 r9 : 00000003 r8 : 83380300 r7 : df9e9d90 r6 : 83380300 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e24a18 r1 : 00000001 r0 : 81433624 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 99c60580 DAC: fffffffd Register r0 information: non-slab/vmalloc memory Register r1 information: non-paged memory Register r2 information: non-slab/vmalloc memory Register r3 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 83380300 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf9e8000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r8 information: slab kmalloc-192 start 83380300 pointer offset 0 size 192 Register r9 information: non-paged memory Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xdf9e8000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdf9e8000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.4.10198 (pid: 22809, stack limit = 0xdf9e8000) Stack: (0xdf9e9d30 to 0xdf9ea000) 9d20: df9e9d4c df9e9d40 829d6700 829d6700 9d40: 81e24ed8 00000000 df9e9d8c df9e9d58 8142f52c 8143384c 40946400 00000000 9d60: df9e9d7c 200000c0 83380300 b5403587 40946400 00000003 00000003 850f9800 9d80: df9e9e4c df9e9d90 8142ad38 8142f42c 656d6f63 705f6964 6f707261 00007472 9da0: 00000000 00004f27 00000000 0000fffe 00000004 00000003 00000cc7 00000004 9dc0: 00080008 0000000e 00000006 00000002 00000001 00000007 00000001 00000006 9de0: 10000103 00000000 0001a44d 00000003 3fff7fff 00000008 00000010 00000000 9e00: 20001e58 00000007 00000e69 0000003c 00000008 0000000a ffffffff effffff8 9e20: 00000000 25c96ce2 00000000 85fa5f00 83380300 200000c0 40946400 00000003 9e40: df9e9f14 df9e9e50 8142c05c 8142ac70 df9e9e4c 25c96ce2 00000000 00000000 9e60: 824b857c df9e9ea4 0000005f 8469f9f0 00000064 83380330 df9e9ee4 df9e9e88 9e80: 807cf200 807c55d8 00000064 00000001 00000000 df9e9ea4 86abbcd0 834e9f68 9ea0: 00006400 0000000b df9e9e98 00000000 df9e9d38 25c96ce2 00000000 85fa5f00 9ec0: 40946400 200000c0 200000c0 85fa5f00 00000003 850f9800 df9e9ef4 df9e9ee8 9ee0: 807cf330 25c96ce2 df9e9f14 00000000 85fa5f01 40946400 200000c0 85fa5f00 9f00: 00000003 850f9800 df9e9fa4 df9e9f18 805906a8 8142bd14 ecac8b10 850f9800 9f20: df9e9f3c df9e9f30 81ae4734 81ae4600 df9e9f54 df9e9f40 8025a824 8028c290 9f40: df9e9fb0 40000000 df9e9f84 df9e9f58 80220bf8 8025a7e0 00000000 8281d2bc 9f60: df9e9fb0 0013e480 ecac8b10 80220b4c 00000000 25c96ce2 df9e9fac 00000000 9f80: 00000000 00346310 00000036 8020029c 850f9800 00000036 00000000 df9e9fa8 9fa0: 80200060 80590470 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f8d0dc 9fe0: 76f8ce88 76f8ce78 00018ba0 001302e0 60000010 00000003 00000000 00000000 Call trace: [<81433840>] (parport_attach) from [<8142f52c>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r6:00000000 r5:81e24ed8 r4:829d6700 [<8142f420>] (comedi_device_attach) from [<8142ad38>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:850f9800 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:83380300 r4:200000c0 [<8142ac64>] (do_devconfig_ioctl) from [<8142c05c>] (comedi_unlocked_ioctl+0x354/0x1dbc drivers/comedi/comedi_fops.c:2300) r8:00000003 r7:40946400 r6:200000c0 r5:83380300 r4:85fa5f00 [<8142bd08>] (comedi_unlocked_ioctl) from [<805906a8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8142bd08>] (comedi_unlocked_ioctl) from [<805906a8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8142bd08>] (comedi_unlocked_ioctl) from [<805906a8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8142bd08>] (comedi_unlocked_ioctl) from [<805906a8>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:850f9800 r9:00000003 r8:85fa5f00 r7:200000c0 r6:40946400 r5:85fa5f01 r4:00000000 [<80590464>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9e9fa8 to 0xdf9e9ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f8d0dc 9fe0: 76f8ce88 76f8ce78 00018ba0 001302e0 r10:00000036 r9:850f9800 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e596306c e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e596306c ldr r3, [r6, #108] @ 0x6c 4: e3a04000 mov r4, #0 8: e7f33053 ubfx r3, r3, #0, #20 c: e2433612 sub r3, r3, #18874368 @ 0x1200000 * 10: e5c34000 strb r4, [r3] <-- trapping instruction