8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f23 when write [fee04f23] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 4069 Comm: syz.0.90 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 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 : [<8140a510>] lr : [<8140a500>] psr: 60000013 sp : dfbd9d28 ip : dfbd9d28 fp : dfbd9d4c r10: 82b28ad8 r9 : 00000003 r8 : 84501300 r7 : dfbd9d88 r6 : 84501300 r5 : 00000000 r4 : 00000000 r3 : fee04f23 r2 : 81e1a398 r1 : 00000001 r0 : 8140a180 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86000f00 DAC: 00000000 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 84501300 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfbd8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 84501300 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 0xdfbd8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfbd8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.90 (pid: 4069, stack limit = 0xdfbd8000) Stack: (0xdfbd9d28 to 0xdfbda000) 9d20: 82433488 84501300 829d3f08 829d3f08 81e1a858 84501344 9d40: dfbd9d84 dfbd9d50 814061bc 8140a3a8 84501330 00000000 dfbd9d74 200000c0 9d60: 84501300 b5403587 84501330 84ee0c00 40946400 00000003 dfbd9e44 dfbd9d88 9d80: 81401b14 814060c0 656d6f63 705f6964 6f707261 00007472 00000000 00004f23 9da0: 00000005 00000002 04000401 00000001 40000cc7 00000fff 5c952399 00000005 9dc0: 000003ff 00000802 00000008 00010001 00000001 00000009 0000e1cb 00000006 9de0: 00000401 00000003 00000395 80000089 fffffffd 00000032 fffffff5 ffffeadb 9e00: 00000007 0000003c 00000008 00000003 08000000 00002ec0 00000000 4f96edca 9e20: 00000003 8598eb40 84501300 200000c0 84501330 84ee0c00 dfbd9f14 dfbd9e48 9e40: 81402b08 81401a20 00000000 00000000 00000000 00000000 00000000 4f96edca 9e60: 00000000 00000000 824a45ec 0000005f 84460250 00000064 8451db94 84ee0c00 9e80: dfbd9ee4 dfbd9e90 807b8730 807aec54 00000064 00000001 00000000 dfbd9eac 9ea0: 85edb850 834306e8 00006400 0000000b dfbd9ea0 00000000 00000000 4f96edca 9ec0: 8598eb40 40946400 200000c0 200000c0 8598eb40 00000003 dfbd9ef4 dfbd9ee8 9ee0: 807b8850 4f96edca dfbd9f14 40946400 00000000 8598eb41 200000c0 8598eb40 9f00: 00000003 84ee0c00 dfbd9fa4 dfbd9f18 80585cc0 81402558 ecac8b10 84ee0c00 9f20: dfbd9f3c dfbd9f30 81ab1624 81ab14f4 dfbd9f54 dfbd9f40 8025bcbc 8028e0c4 9f40: dfbd9fb0 40000000 dfbd9f84 dfbd9f58 80221a38 8025bc78 00000000 8281cf7c 9f60: dfbd9fb0 0014c8c0 ecac8b10 8022198c 00000000 4f96edca dfbd9fac 00000000 9f80: 00000000 00326310 00000036 8020029c 84ee0c00 00000036 00000000 dfbd9fa8 9fa0: 80200060 80585b9c 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fa50bc 9fe0: 76fa4ec0 76fa4eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<8140a39c>] (parport_attach) from [<814061bc>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r6:84501344 r5:81e1a858 r4:829d3f08 [<814060b4>] (comedi_device_attach) from [<81401b14>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:84ee0c00 r7:84501330 r6:b5403587 r5:84501300 r4:200000c0 [<81401a14>] (do_devconfig_ioctl) from [<81402b08>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:84ee0c00 r7:84501330 r6:200000c0 r5:84501300 r4:8598eb40 [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8140254c>] (comedi_unlocked_ioctl) from [<80585cc0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:84ee0c00 r9:00000003 r8:8598eb40 r7:200000c0 r6:8598eb41 r5:00000000 r4:40946400 [<80585b90>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbd9fa8 to 0xdfbd9ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fa50bc 9fe0: 76fa4ec0 76fa4eb0 000192bc 00132360 r10:00000036 r9:84ee0c00 r8:8020029c r7:00000036 r6:00326310 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