8<--- cut here --- Unable to handle kernel paging request at virtual address fee00294 when write [fee00294] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 3889 Comm: syz.1.48 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 : [<8145b8b4>] lr : [<8145b8a4>] psr: 60000013 sp : dfb99d30 ip : dfb99d30 fp : dfb99d54 r10: 82d29754 r9 : 00000003 r8 : 841906c0 r7 : dfb99d90 r6 : 841906c0 r5 : 00000000 r4 : 00000000 r3 : fee00294 r2 : 81e27308 r1 : 00000001 r0 : 8145b514 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8640e800 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 841906c0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfb98000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r8 information: slab kmalloc-192 start 841906c0 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 0xdfb98000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r12 information: 2-page vmalloc region starting at 0xdfb98000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Process syz.1.48 (pid: 3889, stack limit = 0xdfb98000) Stack: (0xdfb99d30 to 0xdfb9a000) 9d20: 824bcb94 841906c0 00000000 82bd2368 9d40: 81e277c8 00000000 dfb99d8c dfb99d58 81457430 8145b73c 40946400 00000000 9d60: dfb99d7c 20000140 841906c0 b5403587 40946400 00000000 00000003 83f67080 9d80: dfb99e4c dfb99d90 81452c3c 81457334 656d6f63 705f6964 6f707261 00007472 9da0: 00000000 00000294 00000002 7fffffff 00000008 0000002f 00002006 000000f1 9dc0: 00000008 00080ffa 00000002 00000000 00008500 00001003 01000004 0000000f 9de0: 00010000 ffffffa8 7ffffffd 000001ff 200009ea 20000010 00040000 00000008 9e00: 00004008 0000746f 00000008 00000005 00000008 7a2e6ff0 00000004 00007ffd 9e20: 00000000 490582c4 00000000 84e06080 841906c0 20000140 40946400 00000000 9e40: dfb99f14 dfb99e50 81453f60 81452b74 00000000 490582c4 00000000 00000000 9e60: 82531804 dfb99ea4 0000005f 841d8b68 00000064 841906f0 dfb99ee4 dfb99e88 9e80: 807eaa84 807e0d98 00000064 00000001 00000000 dfb99ea4 830eb490 834ecbb0 9ea0: 00006400 0000000b dfb99e98 00000000 00000000 490582c4 00000000 84e06080 9ec0: 40946400 20000140 20000140 84e06080 00000003 83f67080 dfb99ef4 dfb99ee8 9ee0: 807eabb8 490582c4 dfb99f14 00000000 84e06081 40946400 20000140 84e06080 9f00: 00000003 83f67080 dfb99fa4 dfb99f18 805a2310 81453c18 ecac8b10 83f67080 9f20: dfb99f3c dfb99f30 81b1b294 81b1b160 dfb99f54 dfb99f40 8025a6ac 8028e2e4 9f40: dfb99fb0 40000000 dfb99f84 dfb99f58 80220be0 8025a668 00000000 82a1c63c 9f60: dfb99fb0 0013e9b0 ecac8b10 80220b34 00000000 490582c4 dfb99fac 00000000 9f80: 00000000 00346310 00000036 8020029c 83f67080 00000036 00000000 dfb99fa8 9fa0: 80200060 805a20d8 00000000 00000000 00000003 40946400 20000140 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f4f0dc 9fe0: 76f4ee88 76f4ee78 00018ebc 00130810 60000010 00000003 00000000 00000000 Call trace: [<8145b730>] (parport_attach) from [<81457430>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e277c8 r4:82bd2368 [<81457328>] (comedi_device_attach) from [<81452c3c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:83f67080 r9:00000003 r8:00000000 r7:40946400 r6:b5403587 r5:841906c0 r4:20000140 [<81452b68>] (do_devconfig_ioctl) from [<81453f60>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000000 r7:40946400 r6:20000140 r5:841906c0 r4:84e06080 [<81453c0c>] (comedi_unlocked_ioctl) from [<805a2310>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81453c0c>] (comedi_unlocked_ioctl) from [<805a2310>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81453c0c>] (comedi_unlocked_ioctl) from [<805a2310>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81453c0c>] (comedi_unlocked_ioctl) from [<805a2310>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83f67080 r9:00000003 r8:84e06080 r7:20000140 r6:40946400 r5:84e06081 r4:00000000 [<805a20cc>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb99fa8 to 0xdfb99ff0) 9fa0: 00000000 00000000 00000003 40946400 20000140 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f4f0dc 9fe0: 76f4ee88 76f4ee78 00018ebc 00130810 r10:00000036 r9:83f67080 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