8<--- cut here --- Unable to handle kernel paging request at virtual address fee00103 when write [fee00103] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 29507 Comm: syz.1.6469 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 : [<814162b4>] lr : [<814162a0>] psr: 60000013 sp : ee375cb0 ip : ee375cb0 fp : ee375ccc r10: 00000001 r9 : 00000084 r8 : ee375d9c r7 : 00000100 r6 : 0000009b r5 : 844e73c0 r4 : 00000103 r3 : 0000009b r2 : fee00103 r1 : 00000001 r0 : 844e73c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 862d2740 DAC: fffffffd Register r0 information: slab kmalloc-192 start 844e73c0 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 844e73c0 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 0xee374000 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 0xee374000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xee374000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.1.6469 (pid: 29507, stack limit = 0xee374000) Stack: (0xee375cb0 to 0xee376000) 5ca0: 81416254 844e73c0 00000100 00000100 5cc0: ee375cec ee375cd0 81415f8c 81416260 00000100 805150ac 83efb000 83efb000 5ce0: ee375d0c ee375cf0 8141634c 81415f40 844e73c0 00000000 83efb000 00000100 5d00: ee375d4c ee375d10 814164f8 814162cc 0000005f 844f9200 828217b0 00000000 5d20: 00000000 829d46a0 844e73c0 844e7404 ee375d88 844e73c0 00000000 82b28ad8 5d40: ee375d84 ee375d50 8140502c 81416490 844e73f0 00000000 ee375d74 200000c0 5d60: 844e73c0 b5403587 844e73f0 85a81800 40946400 00000003 ee375e44 ee375d88 5d80: 81400984 81404f30 35353238 00000000 00000000 00000000 00000000 00000100 5da0: 00010005 80000001 00000008 0000000c 00000003 00000fff 5c95238c 0000000b 5dc0: 00000020 00000806 000015fa 00000005 20000001 00000809 0000002f fffffff9 5de0: 00000007 00000002 fffffffc 00000008 00008004 0000000b 00000001 fffffffb 5e00: 00800003 000000ef 00000000 0008000a 08000003 0000d262 00000000 76cbff70 5e20: 00000000 86135f00 844e73c0 200000c0 844e73f0 85a81800 ee375f14 ee375e48 5e40: 81401978 81400890 00000000 00000000 00000000 ee375e54 ee375e54 76cbff70 5e60: 00000000 00000000 824a45ec 0000005f 84134448 00000064 84678a74 85a81800 5e80: ee375ee4 ee375e90 807b8180 807ae6a4 00000064 00000001 00000000 ee375eac 5ea0: 862cec10 834d7550 00006400 0000000b ee375ea0 00000000 ee375d40 76cbff70 5ec0: 86135f00 40946400 200000c0 200000c0 86135f00 00000003 ee375ef4 ee375ee8 5ee0: 807b82a0 76cbff70 ee375f14 40946400 00000000 86135f01 200000c0 86135f00 5f00: 00000003 85a81800 ee375fa4 ee375f18 80585768 814013c8 ecac8b10 85a81800 5f20: ee375f3c ee375f30 81ab01ac 81ab007c ee375f54 ee375f40 8025bcbc 8028e0c4 5f40: ee375fb0 40000000 ee375f84 ee375f58 80221a38 8025bc78 00000000 8281d17c 5f60: ee375fb0 0014c8c0 ecac8b10 8022198c 00000000 76cbff70 ee375fac 00000000 5f80: 00000000 00326310 00000036 8020029c 85a81800 00000036 00000000 ee375fa8 5fa0: 80200060 80585644 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fcf0bc 5fe0: 76fceec0 76fceeb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81416254>] (subdev_8255_io) from [<81415f8c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000100 r6:00000100 r5:844e73c0 r4:81416254 [<81415f34>] (subdev_8255_do_config) from [<8141634c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81415f34>] (subdev_8255_do_config) from [<8141634c>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:83efb000 [<814162c0>] (subdev_8255_io_init) from [<814164f8>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<814162c0>] (subdev_8255_io_init) from [<814164f8>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00000100 r6:83efb000 r5:00000000 r4:844e73c0 [<81416484>] (dev_8255_attach) from [<8140502c>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:844e73c0 r7:ee375d88 r6:844e7404 r5:844e73c0 r4:829d46a0 [<81404f24>] (comedi_device_attach) from [<81400984>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:85a81800 r7:844e73f0 r6:b5403587 r5:844e73c0 r4:200000c0 [<81400884>] (do_devconfig_ioctl) from [<81401978>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:85a81800 r7:844e73f0 r6:200000c0 r5:844e73c0 r4:86135f00 [<814013bc>] (comedi_unlocked_ioctl) from [<80585768>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814013bc>] (comedi_unlocked_ioctl) from [<80585768>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814013bc>] (comedi_unlocked_ioctl) from [<80585768>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814013bc>] (comedi_unlocked_ioctl) from [<80585768>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:85a81800 r9:00000003 r8:86135f00 r7:200000c0 r6:86135f01 r5:00000000 r4:40946400 [<80585638>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xee375fa8 to 0xee375ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fcf0bc 5fe0: 76fceec0 76fceeb0 000192bc 00132360 r10:00000036 r9:85a81800 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