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: 4994 Comm: syz.2.263 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: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 : [<81408d38>] lr : [<81408d28>] psr: 60000013 sp : dfc6dd28 ip : dfc6dd28 fp : dfc6dd4c r10: 82b28ad8 r9 : 00000003 r8 : 845c5540 r7 : dfc6dd88 r6 : 845c5540 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e1a2b8 r1 : 00000001 r0 : 814089a8 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84d9c800 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 845c5540 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfc6c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 845c5540 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 0xdfc6c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfc6c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.2.263 (pid: 4994, stack limit = 0xdfc6c000) Stack: (0xdfc6dd28 to 0xdfc6e000) dd20: dfc6dd44 dfc6dd38 829d3f08 829d3f08 81e1a778 845c5584 dd40: dfc6dd84 dfc6dd50 814049e0 81408bd0 845c5570 00000000 dfc6dd74 200000c0 dd60: 845c5540 b5403587 845c5570 83e33c00 40946400 00000003 dfc6de44 dfc6dd88 dd80: 81400338 814048e4 656d6f63 705f6964 6f707261 00007472 00000000 00004f27 dda0: 00000000 00000004 00000004 00000005 00000005 00000007 00000007 54c6cff3 ddc0: 000000fd 00000002 00000007 00000001 00000001 00000006 00000005 00000000 dde0: 0000007f 00000003 40000003 00000089 0000caa3 00000000 20001e5b 00000003 de00: 00000e66 00000003 00000008 00004086 00000000 fffffff8 00000000 d61a5cca de20: 00000000 84cf5000 845c5540 200000c0 845c5570 83e33c00 dfc6df14 dfc6de48 de40: 8140132c 81400244 00000000 00000000 00000000 00000000 00000000 d61a5cca de60: 00000000 00000000 824a35ec 0000005f 8466ec28 00000064 845503fc 83e33c00 de80: dfc6dee4 dfc6de90 807b7f80 807ae4a4 00000064 00000001 00000000 dfc6deac dea0: 85fa5f10 835b4c38 00006400 0000000b dfc6dea0 00000000 00000000 d61a5cca dec0: 84cf5000 40946400 200000c0 200000c0 84cf5000 00000003 dfc6def4 dfc6dee8 dee0: 807b80a0 d61a5cca dfc6df14 40946400 00000000 84cf5001 200000c0 84cf5000 df00: 00000003 83e33c00 dfc6dfa4 dfc6df18 80585608 81400d7c ecac8b10 83e33c00 df20: dfc6df3c dfc6df30 81aaf9ac 81aaf87c dfc6df54 dfc6df40 8025bcbc 8028e0c4 df40: dfc6dfb0 40000000 dfc6df84 dfc6df58 80221a38 8025bc78 00000000 8281d17c df60: dfc6dfb0 0014c8c0 ecac8b10 8022198c 00000000 d61a5cca dfc6dfac 00000000 df80: 00000000 00326310 00000036 8020029c 83e33c00 00000036 00000000 dfc6dfa8 dfa0: 80200060 805854e4 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fae0bc dfe0: 76fadec0 76fadeb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81408bc4>] (parport_attach) from [<814049e0>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r6:845c5584 r5:81e1a778 r4:829d3f08 [<814048d8>] (comedi_device_attach) from [<81400338>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:83e33c00 r7:845c5570 r6:b5403587 r5:845c5540 r4:200000c0 [<81400238>] (do_devconfig_ioctl) from [<8140132c>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:83e33c00 r7:845c5570 r6:200000c0 r5:845c5540 r4:84cf5000 [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83e33c00 r9:00000003 r8:84cf5000 r7:200000c0 r6:84cf5001 r5:00000000 r4:40946400 [<805854d8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfc6dfa8 to 0xdfc6dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fae0bc dfe0: 76fadec0 76fadeb0 000192bc 00132360 r10:00000036 r9:83e33c00 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