8<--- cut here --- Unable to handle kernel paging request at virtual address fee08004 when write [fee08004] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 10121 Comm: syz.2.1576 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 : [<813dbdc8>] lr : [<813dbdb4>] psr: 60000013 sp : ea7b5cb8 ip : ea7b5cb8 fp : ea7b5cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00008001 r6 : 0000009b r5 : 84173540 r4 : 00008004 r3 : 0000009b r2 : fee08004 r1 : 00000001 r0 : 84173540 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85712a80 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84173540 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 84173540 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xea7b4000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xea7b4000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.2.1576 (pid: 10121, stack limit = 0xea7b4000) Stack: (0xea7b5cb8 to 0xea7b6000) 5ca0: 813dbd68 84173540 5cc0: 00008001 00008001 ea7b5cf4 ea7b5cd8 813dbaa0 813dbd74 00008001 8050a85c 5ce0: 84b77000 84b77000 ea7b5d14 ea7b5cf8 813dbe60 813dba54 84b77000 84173540 5d00: ea7b5da4 00008001 ea7b5d54 ea7b5d18 813dc054 813dbde0 82af1fe0 83bfd900 5d20: 828215f0 00000000 00000000 829d23cc 84173540 84173584 ea7b5d90 84173540 5d40: 00000000 82b25910 ea7b5d8c ea7b5d58 813caf4c 813dbfa4 200001c0 00000000 5d60: ea7b5d7c 200001c0 84173540 b5403587 200001c0 83b58c00 40946400 00000003 5d80: ea7b5e4c ea7b5d90 813c6a98 813cae50 35353238 00000000 00000000 00000000 5da0: 00000000 00008001 00000009 00000001 00000009 00000004 00000ccb 00000008 5dc0: 000000ab 00000000 000000fd fffffffd 00000080 00000005 00000002 00000006 5de0: ffffffff 00000002 00000040 000000d9 40000003 ffffffff 00001000 00001000 5e00: 00000045 fffffffc 00010000 0000003c 00000000 4000000c 00000004 ffffffff 5e20: 00000000 2f778927 00000000 85a7db40 84173540 200001c0 200001c0 83b58c00 5e40: ea7b5f14 ea7b5e50 813c7a64 813c69a4 00000000 00000000 00000000 2f778927 5e60: 00000000 00000000 824625b4 0000005f 83e5d600 84173570 8415abdc 83b58c00 5e80: ea7b5ee4 ea7b5e90 807a7a88 8079e1d4 00000064 00000001 00000000 ea7b5eac 5ea0: 858c23d0 8342dcc0 00006400 0000000b ea7b5ea0 00000000 00000000 2f778927 5ec0: 85a7db40 40946400 200001c0 200001c0 85a7db40 00000003 ea7b5ef4 ea7b5ee8 5ee0: 807a7ba8 2f778927 ea7b5f14 40946400 00000000 85a7db41 200001c0 85a7db40 5f00: 00000003 83b58c00 ea7b5fa4 ea7b5f18 80578f40 813c7494 ecac8b10 83b58c00 5f20: ea7b5f3c ea7b5f30 81a618c0 81a61790 ea7b5f54 ea7b5f40 8025c484 8028d914 5f40: ea7b5fb0 40000000 ea7b5f84 ea7b5f58 802229ec 8025c440 00000000 8281cfb4 5f60: ea7b5fb0 0014cf70 ecac8b10 80222940 00000000 2f778927 ea7b5fac 00000000 5f80: 00000000 00316308 00000036 8020029c 83b58c00 00000036 00000000 ea7b5fa8 5fa0: 80200060 80578e1c 00000000 00000000 00000003 40946400 200001c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fec0bc 5fe0: 76febec0 76febeb0 00019294 00132a10 60000010 00000003 00000000 00000000 Call trace: [<813dbd68>] (subdev_8255_io) from [<813dbaa0>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00008001 r6:00008001 r5:84173540 r4:813dbd68 [<813dba48>] (subdev_8255_do_config) from [<813dbe60>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813dba48>] (subdev_8255_do_config) from [<813dbe60>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84b77000 [<813dbdd4>] (subdev_8255_io_init) from [<813dc054>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813dbdd4>] (subdev_8255_io_init) from [<813dc054>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00008001 r6:ea7b5da4 r5:84173540 r4:84b77000 [<813dbf98>] (dev_8255_attach) from [<813caf4c>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84173540 r7:ea7b5d90 r6:84173584 r5:84173540 r4:829d23cc [<813cae44>] (comedi_device_attach) from [<813c6a98>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83b58c00 r7:200001c0 r6:b5403587 r5:84173540 r4:200001c0 [<813c6998>] (do_devconfig_ioctl) from [<813c7a64>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83b58c00 r7:200001c0 r6:200001c0 r5:84173540 r4:85a7db40 [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83b58c00 r9:00000003 r8:85a7db40 r7:200001c0 r6:85a7db41 r5:00000000 r4:40946400 [<80578e10>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea7b5fa8 to 0xea7b5ff0) 5fa0: 00000000 00000000 00000003 40946400 200001c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fec0bc 5fe0: 76febec0 76febeb0 00019294 00132a10 r10:00000036 r9:83b58c00 r8:8020029c r7:00000036 r6:00316308 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