8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f27 when write [fee04f27] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 15668 Comm: syz.7.2336 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 : [<813ac9b0>] lr : [<813ac9a0>] psr: 60000013 sp : dfcb1d30 ip : dfcb1d30 fp : dfcb1d54 r10: 82b16f40 r9 : 00000003 r8 : 83cdf900 r7 : dfcb1d90 r6 : 83cdf900 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e15644 r1 : 00000001 r0 : 813ac620 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 868b0dc0 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:1055 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 83cdf900 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfcb0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r8 information: slab kmalloc-192 start 83cdf900 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 0xdfcb0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfcb0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.7.2336 (pid: 15668, stack limit = 0xdfcb0000) Stack: (0xdfcb1d30 to 0xdfcb2000) 1d20: dfcb1d4c dfcb1d40 829cf9ac 829cf9ac 1d40: 81e15b04 83cdf944 dfcb1d8c dfcb1d58 813a8a48 813ac848 200003c0 00000000 1d60: dfcb1d7c 200003c0 83cdf900 b5403587 200003c0 855ad400 40946400 00000003 1d80: dfcb1e4c dfcb1d90 813a4594 813a894c 656d6f63 705f6964 6f707261 00007472 1da0: 00000000 00004f27 00000000 00000000 000004cd 00000005 00000006 00040004 1dc0: 00000007 7fffffff 00000104 00000007 00000fff 00000005 00020003 00000009 1de0: 00000101 00000003 7ffffffd 00000005 40000003 00000087 0000caab 0000000e 1e00: ffffffff 0000000b 00000e69 0000003c 0000000c 00008000 000003a0 00000003 1e20: 00000000 03d8c213 00000000 866a10c0 83cdf900 200003c0 200003c0 855ad400 1e40: dfcb1f14 dfcb1e50 813a5560 813a44a0 00000000 dfcb1e54 dfcb1e54 03d8c213 1e60: 00000000 00000000 8247154c 0000005f 8427ea58 83cdf930 83d335f4 855ad400 1e80: dfcb1ee4 dfcb1e90 80797ecc 8078e230 00000064 00000001 00000000 dfcb1eac 1ea0: 856c73d0 83424000 00006400 0000000b dfcb1ea0 00000000 dfcb1d30 03d8c213 1ec0: 866a10c0 40946400 200003c0 200003c0 866a10c0 00000003 dfcb1ef4 dfcb1ee8 1ee0: 80797fec 03d8c213 dfcb1f14 40946400 00000000 866a10c1 200003c0 866a10c0 1f00: 00000003 855ad400 dfcb1fa4 dfcb1f18 8056d0cc 813a4f90 ecac8b10 855ad400 1f20: dfcb1f3c dfcb1f30 81a3b398 81a3b268 dfcb1f54 dfcb1f40 8025e490 8028ef6c 1f40: dfcb1fb0 40000000 dfcb1f84 dfcb1f58 802229ec 8025e44c 00000000 8281cddc 1f60: dfcb1fb0 0014c800 ecac8b10 80222940 00000000 03d8c213 dfcb1fac 00000000 1f80: 00000000 00306308 00000036 8020029c 855ad400 00000036 00000000 dfcb1fa8 1fa0: 80200060 8056cfa8 00000000 00000000 00000003 40946400 200003c0 00000000 1fc0: 00000000 00000000 00306308 00000036 002f0000 00000000 00006364 76fb70bc 1fe0: 76fb6ec0 76fb6eb0 0001948c 001322a0 60000010 00000003 00000000 00000000 Call trace: [<813ac83c>] (parport_attach) from [<813a8a48>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r6:83cdf944 r5:81e15b04 r4:829cf9ac [<813a8940>] (comedi_device_attach) from [<813a4594>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:855ad400 r7:200003c0 r6:b5403587 r5:83cdf900 r4:200003c0 [<813a4494>] (do_devconfig_ioctl) from [<813a5560>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:855ad400 r7:200003c0 r6:200003c0 r5:83cdf900 r4:866a10c0 [<813a4f84>] (comedi_unlocked_ioctl) from [<8056d0cc>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a4f84>] (comedi_unlocked_ioctl) from [<8056d0cc>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a4f84>] (comedi_unlocked_ioctl) from [<8056d0cc>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a4f84>] (comedi_unlocked_ioctl) from [<8056d0cc>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:855ad400 r9:00000003 r8:866a10c0 r7:200003c0 r6:866a10c1 r5:00000000 r4:40946400 [<8056cf9c>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfcb1fa8 to 0xdfcb1ff0) 1fa0: 00000000 00000000 00000003 40946400 200003c0 00000000 1fc0: 00000000 00000000 00306308 00000036 002f0000 00000000 00006364 76fb70bc 1fe0: 76fb6ec0 76fb6eb0 0001948c 001322a0 r10:00000036 r9:855ad400 r8:8020029c r7:00000036 r6:00306308 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