8<--- cut here --- Unable to handle kernel paging request at virtual address fee00400 when write [fee00400] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 6511 Comm: syz.3.372 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: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 : [<8144de6c>] lr : [<8144de5c>] psr: 60000013 sp : e00e1d30 ip : e00e1d30 fp : e00e1d54 r10: 82d2bdc4 r9 : 00000003 r8 : 8301a6c0 r7 : e00e1d90 r6 : 8301a6c0 r5 : 00000000 r4 : 00000000 r3 : fee00400 r2 : 81e27468 r1 : 00000001 r0 : 8144dacc Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 866879c0 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 8301a6c0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xe00e0000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2721 Register r8 information: slab kmalloc-192 start 8301a6c0 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 0xe00e0000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2721 Register r12 information: 2-page vmalloc region starting at 0xe00e0000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2721 Process syz.3.372 (pid: 6511, stack limit = 0xe00e0000) Stack: (0xe00e1d30 to 0xe00e2000) 1d20: 824ba914 8301a6c0 00000000 82bd27a0 1d40: 81e27928 00000000 e00e1d8c e00e1d58 814499cc 8144dcf4 40946400 00000000 1d60: e00e1d7c 20000140 8301a6c0 b5403587 40946400 00000001 0000000b 84686200 1d80: e00e1e4c e00e1d90 814451d8 814498d0 656d6f63 705f6964 6f707261 00007472 1da0: 00000000 00000400 00000002 7fffffff 000084e1 0000002f 00002006 00000006 1dc0: 00000008 000a0ffa 00000000 00000007 00000002 00001003 01000004 0000000f 1de0: 00010000 ffffffa8 7ffbfffd 000001ff 0000ecd0 00000010 0003fffe 00000008 1e00: 00000007 0000746f 00000004 00000005 00000408 00000004 00000000 00007ffd 1e20: 00000000 dcb4da92 00000000 85b3e700 8301a6c0 20000140 40946400 00000001 1e40: e00e1f14 e00e1e50 814464fc 81445110 00000000 dcb4da92 00000000 00000000 1e60: 8252f804 e00e1ea4 0000005f 8427d0f0 00000064 8301a6f0 e00e1ee4 e00e1e88 1e80: 807df0b0 807d53c4 00000064 00000001 00000000 e00e1ea4 830eacd0 834ddf68 1ea0: 00006400 0000000b e00e1e98 00000000 00000000 dcb4da92 00000000 85b3e700 1ec0: 40946400 20000140 20000140 85b3e700 0000000b 84686200 e00e1ef4 e00e1ee8 1ee0: 807df1e4 dcb4da92 e00e1f14 00000000 85b3e701 40946400 20000140 85b3e700 1f00: 0000000b 84686200 e00e1fa4 e00e1f18 8059c1ac 814461b4 ecac8b10 84686200 1f20: e00e1f3c e00e1f30 81b074b4 81b07380 e00e1f54 e00e1f40 8025a49c 8028c280 1f40: e00e1fb0 40000000 e00e1f84 e00e1f58 80220be0 8025a458 00000000 82a1c2fc 1f60: e00e1fb0 0013e940 ecac8b10 80220b34 00000000 dcb4da92 e00e1fac 00000000 1f80: 00000000 00346590 00000036 8020029c 84686200 00000036 00000000 e00e1fa8 1fa0: 80200060 8059bf74 00000000 00000000 0000000b 40946400 20000140 00000000 1fc0: 00000000 00000000 00346590 00000036 00346558 00000000 00000001 76f570dc 1fe0: 76f56e88 76f56e78 00018e58 001307a0 60000010 0000000b 00000000 00000000 Call trace: [<8144dce8>] (parport_attach) from [<814499cc>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e27928 r4:82bd27a0 [<814498c4>] (comedi_device_attach) from [<814451d8>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:84686200 r9:0000000b r8:00000001 r7:40946400 r6:b5403587 r5:8301a6c0 r4:20000140 [<81445104>] (do_devconfig_ioctl) from [<814464fc>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000140 r5:8301a6c0 r4:85b3e700 [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:84686200 r9:0000000b r8:85b3e700 r7:20000140 r6:40946400 r5:85b3e701 r4:00000000 [<8059bf68>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe00e1fa8 to 0xe00e1ff0) 1fa0: 00000000 00000000 0000000b 40946400 20000140 00000000 1fc0: 00000000 00000000 00346590 00000036 00346558 00000000 00000001 76f570dc 1fe0: 76f56e88 76f56e78 00018e58 001307a0 r10:00000036 r9:84686200 r8:8020029c r7:00000036 r6:00346590 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