8<--- cut here --- Unable to handle kernel paging request at virtual address fee00140 when write [fee00140] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 3771 Comm: syz.1.17 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [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 : [<814913c4>] lr : [<814913b4>] psr: 60000013 sp : e0369d30 ip : e0369d30 fp : e0369d54 r10: 82d30dfc r9 : 00000003 r8 : 8466bc00 r7 : e0369d90 r6 : 8466bc00 r5 : 00000000 r4 : 00000000 r3 : fee00140 r2 : 81e2dc88 r1 : 00000001 r0 : 81491024 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 868b0880 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:1048 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 8466bc00 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xe0368000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Register r8 information: slab kmalloc-192 start 8466bc00 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 0xe0368000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Register r12 information: 2-page vmalloc region starting at 0xe0368000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Process syz.1.17 (pid: 3771, stack limit = 0xe0368000) Stack: (0xe0369d30 to 0xe036a000) 9d20: 824d3f9c 8466bc00 82bd8e44 82bd8e44 9d40: 81e2e148 00000000 e0369d8c e0369d58 8148cf3c 8149124c 40946400 00000000 9d60: e0369d7c 200003c0 8466bc00 b5403587 40946400 00000002 00000003 847abd40 9d80: e0369e4c e0369d90 81488740 8148ce40 656d6f63 705f6964 6f707261 00007472 9da0: 00000000 00000140 fffffffc 0001000c 0000dddc 00000000 00010000 00007fff 9dc0: 00000006 00000007 0000c72c 02000004 0000000f 0000c000 00000008 000004ce 9de0: 00008e99 00000001 000000ed 00000006 00000008 00000004 00000000 0000000a 9e00: 00000009 00000ffd 00000009 000000af 00000002 00000283 00008001 0000e43f 9e20: 00000000 495c93f9 00000000 833f2e00 8466bc00 200003c0 40946400 00000002 9e40: e0369f14 e0369e50 81489a68 81488680 00000000 495c93f9 00000000 00000000 9e60: 8254880c e0369ea4 0000005f 843aa990 00000064 8466bc30 e0369ee4 e0369e88 9e80: 80804fec 807fb31c 00000064 00000001 00000000 e0369ea4 85284f10 834e14c8 9ea0: 00006400 0000000b e0369e98 00000000 00000000 495c93f9 5b4fd000 833f2e00 9ec0: 40946400 200003c0 200003c0 833f2e00 00000003 847abd40 e0369ef4 e0369ee8 9ee0: 80805120 495c93f9 e0369f14 00000000 833f2e01 40946400 200003c0 833f2e00 9f00: 00000003 847abd40 e0369fa4 e0369f18 805ba7e8 81489720 ecac8b10 847abd40 9f20: e0369f3c e0369f30 81b54ac0 81b5498c e0369f54 e0369f40 8025a7ac 8028e488 9f40: e0369fb0 40000000 e0369f84 e0369f58 80220bdc 8025a768 00000000 82a1eb0c 9f60: e0369fb0 0013e9c0 ecac8b10 80220b30 00000000 495c93f9 e0369fac 00000000 9f80: 00000000 00346310 00000036 8020029c 847abd40 00000036 00000000 e0369fa8 9fa0: 80200060 805ba5b0 00000000 00000000 00000003 40946400 200003c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f290dc 9fe0: 76f28e88 76f28e78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<81491240>] (parport_attach) from [<8148cf3c>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e148 r4:82bd8e44 [<8148ce34>] (comedi_device_attach) from [<81488740>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:847abd40 r9:00000003 r8:00000002 r7:40946400 r6:b5403587 r5:8466bc00 r4:200003c0 [<81488674>] (do_devconfig_ioctl) from [<81489a68>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000002 r7:40946400 r6:200003c0 r5:8466bc00 r4:833f2e00 [<81489714>] (comedi_unlocked_ioctl) from [<805ba7e8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81489714>] (comedi_unlocked_ioctl) from [<805ba7e8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81489714>] (comedi_unlocked_ioctl) from [<805ba7e8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81489714>] (comedi_unlocked_ioctl) from [<805ba7e8>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:847abd40 r9:00000003 r8:833f2e00 r7:200003c0 r6:40946400 r5:833f2e01 r4:00000000 [<805ba5a4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0369fa8 to 0xe0369ff0) 9fa0: 00000000 00000000 00000003 40946400 200003c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f290dc 9fe0: 76f28e88 76f28e78 00018ebc 00130820 r10:00000036 r9:847abd40 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