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: 5136 Comm: syz.1.345 Not tainted 6.16.0-rc5-syzkaller #0 PREEMPT 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 : [<81397d48>] lr : [<81397d38>] psr: 60000013 sp : dfae1d38 ip : dfae1d38 fp : dfae1d5c r10: 82b15078 r9 : 00000003 r8 : 8418ad80 r7 : dfae1d98 r6 : 8418ad80 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e14f2c r1 : 00000001 r0 : 813979b8 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85a5a040 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 8418ad80 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfae0000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2599 Register r8 information: slab kmalloc-192 start 8418ad80 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 0xdfae0000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2599 Register r12 information: 2-page vmalloc region starting at 0xdfae0000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2599 Process syz.1.345 (pid: 5136, stack limit = 0xdfae0000) Stack: (0xdfae1d38 to 0xdfae2000) 1d20: 823f8830 8418ad80 1d40: 829c4ad8 829c4ad8 81e153ec 00000000 dfae1d94 dfae1d60 81393e00 81397be0 1d60: 200000c0 00000000 dfae1d84 200000c0 8418ad80 b5403587 200000c0 85dfe000 1d80: 40946400 00000003 dfae1e4c dfae1d98 8138fa90 81393d08 656d6f63 705f6964 1da0: 6f707261 00007472 00000000 00004f27 00000009 00000004 00000004 00000005 1dc0: 00000006 00000006 00000007 0000000a 00000100 00000002 00080003 00000001 1de0: 00000008 0000001e 00000001 00000000 0001a449 00000003 00200006 00000081 1e00: 0000caa7 00000004 00001e58 0000000b 00000003 0000003c 00000008 00000006 1e20: 00000000 00000005 00000000 9ca89ead 00000000 859dc6c0 8418ad80 200000c0 1e40: dfae1f14 dfae1e50 81390a44 8138f9c4 00000000 00000000 00000000 9ca89ead 1e60: 00000000 00000000 8246a3fc 0000005f 83c24458 8418adb0 841a9684 85dfe000 1e80: dfae1ee4 dfae1e90 80795a0c 8078bcfc 00000064 00000001 00000000 dfae1eac 1ea0: 85bc9a90 834343b8 00006400 0000000b dfae1ea0 00000000 dfae1fa4 dfae1ec8 1ec0: 80200bcc 819fb9a4 859dc6c0 40946400 200000c0 81390468 40946400 00000000 1ee0: 859dc6c1 9ca89ead 00000003 40946400 00000000 859dc6c1 200000c0 00000003 1f00: 859dc6c0 85dfe000 dfae1fa4 dfae1f18 8056e2dc 81390474 ecac8b10 85dfe000 1f20: dfae1f3c dfae1f30 81a2cd08 81a2cbd8 dfae1f54 dfae1f40 80261ffc 80293598 1f40: dfae1fb0 40000000 dfae1f84 dfae1f58 802229ec 80261fb8 00000000 8281d09c 1f60: dfae1fb0 0014c4a0 ecac8b10 80222940 00000000 9ca89ead dfae1fac 00000000 1f80: 00000000 002f6300 00000036 8020029c 85dfe000 00000036 00000000 dfae1fa8 1fa0: 80200060 8056e1b8 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6300 00000036 002e0000 00000000 00006364 76b3a0bc 1fe0: 76b39ec0 76b39eb0 000193a4 00131f40 60000010 00000003 00000000 00000000 Call trace: [<81397bd4>] (parport_attach) from [<81393e00>] (comedi_device_attach+0x104/0x240 drivers/comedi/drivers.c:996) r6:00000000 r5:81e153ec r4:829c4ad8 [<81393cfc>] (comedi_device_attach) from [<8138fa90>] (do_devconfig_ioctl+0xd8/0x1e0 drivers/comedi/comedi_fops.c:855) r10:00000003 r9:40946400 r8:85dfe000 r7:200000c0 r6:b5403587 r5:8418ad80 r4:200000c0 [<8138f9b8>] (do_devconfig_ioctl) from [<81390a44>] (comedi_unlocked_ioctl+0x5dc/0x1b94 drivers/comedi/comedi_fops.c:2136) r6:200000c0 r5:8418ad80 r4:859dc6c0 [<81390468>] (comedi_unlocked_ioctl) from [<8056e2dc>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81390468>] (comedi_unlocked_ioctl) from [<8056e2dc>] (do_vfs_ioctl fs/ioctl.c:861 [inline]) [<81390468>] (comedi_unlocked_ioctl) from [<8056e2dc>] (__do_sys_ioctl fs/ioctl.c:905 [inline]) [<81390468>] (comedi_unlocked_ioctl) from [<8056e2dc>] (sys_ioctl+0x130/0xdc8 fs/ioctl.c:893) r10:85dfe000 r9:859dc6c0 r8:00000003 r7:200000c0 r6:859dc6c1 r5:00000000 r4:40946400 [<8056e1ac>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfae1fa8 to 0xdfae1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6300 00000036 002e0000 00000000 00006364 76b3a0bc 1fe0: 76b39ec0 76b39eb0 000193a4 00131f40 r10:00000036 r9:85dfe000 r8:8020029c r7:00000036 r6:002f6300 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