8<--- cut here --- Unable to handle kernel paging request at virtual address fee00100 when write [fee00100] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 31156 Comm: syz.6.5085 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:291 [inline] PC is at parport_attach+0x184/0x1e0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:291 [inline] LR is at parport_attach+0x174/0x1e0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<8145b7b4>] lr : [<8145b7a4>] psr: 60000113 sp : dfaadd30 ip : dfaadd30 fp : dfaadd54 r10: 82d29754 r9 : 00000003 r8 : 8461acc0 r7 : dfaadd90 r6 : 8461acc0 r5 : 00000000 r4 : 00000000 r3 : fee00100 r2 : 81e27308 r1 : 00000001 r0 : 8145b414 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 87deadc0 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:1048 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 8461acc0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfaac000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r8 information: slab kmalloc-192 start 8461acc0 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 0xdfaac000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r12 information: 2-page vmalloc region starting at 0xdfaac000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Process syz.6.5085 (pid: 31156, stack limit = 0xdfaac000) Stack: (0xdfaadd30 to 0xdfaae000) dd20: 824bca50 8461acc0 00000000 82bd2268 dd40: 81e277c8 00000000 dfaadd8c dfaadd58 81457330 8145b63c 40946400 00000000 dd60: dfaadd7c 200000c0 8461acc0 b5403587 40946400 00000003 00000003 83e53e80 dd80: dfaade4c dfaadd90 81452b3c 81457234 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00000100 80000000 00000002 00000010 0000000e 00000005 00000079 ddc0: 00000003 00080008 00000000 00000007 00000001 00000007 00000001 00000005 dde0: 000000fd fffffffb 0000000d 00000003 7fffffff ffffffff 00000004 00000000 de00: 00000003 ffffffff 0000f39e 00000003 00000008 00000006 00000000 fffffff8 de20: 00000000 82f24790 00000000 838cd900 8461acc0 200000c0 40946400 00000003 de40: dfaadf14 dfaade50 81453e60 81452a74 dfaade4c 82f24790 00000000 00000000 de60: 82531804 dfaadea4 0000005f 84598d40 00000064 8461acf0 dfaadee4 dfaade88 de80: 807ea9c4 807e0cd8 00000064 00000001 00000000 dfaadea4 86f64250 8343a550 dea0: 00006400 0000000b dfaade98 00000000 dfaadd38 82f24790 00000000 838cd900 dec0: 40946400 200000c0 200000c0 838cd900 00000003 83e53e80 dfaadef4 dfaadee8 dee0: 807eaaf8 82f24790 dfaadf14 00000000 838cd901 40946400 200000c0 838cd900 df00: 00000003 83e53e80 dfaadfa4 dfaadf18 805a2320 81453b18 ecac8b10 83e53e80 df20: dfaadf3c dfaadf30 81b1af54 81b1ae20 dfaadf54 dfaadf40 8025a6ac 8028e294 df40: dfaadfb0 40000000 dfaadf84 dfaadf58 80220be0 8025a668 00000000 82a1c63c df60: dfaadfb0 0013e9b0 ecac8b10 80220b34 00000000 82f24790 dfaadfac 00000000 df80: 00000000 00346310 00000036 8020029c 83e53e80 00000036 00000000 dfaadfa8 dfa0: 80200060 805a20e8 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f120dc dfe0: 76f11e88 76f11e78 00018ebc 00130810 60000010 00000003 00000000 00000000 Call trace: [<8145b630>] (parport_attach) from [<81457330>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e277c8 r4:82bd2268 [<81457228>] (comedi_device_attach) from [<81452b3c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:83e53e80 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:8461acc0 r4:200000c0 [<81452a68>] (do_devconfig_ioctl) from [<81453e60>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:200000c0 r5:8461acc0 r4:838cd900 [<81453b0c>] (comedi_unlocked_ioctl) from [<805a2320>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81453b0c>] (comedi_unlocked_ioctl) from [<805a2320>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81453b0c>] (comedi_unlocked_ioctl) from [<805a2320>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81453b0c>] (comedi_unlocked_ioctl) from [<805a2320>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83e53e80 r9:00000003 r8:838cd900 r7:200000c0 r6:40946400 r5:838cd901 r4:00000000 [<805a20dc>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfaadfa8 to 0xdfaadff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f120dc dfe0: 76f11e88 76f11e78 00018ebc 00130810 r10:00000036 r9:83e53e80 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e5963064 e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e5963064 ldr r3, [r6, #100] @ 0x64 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