8<--- cut here --- Unable to handle kernel paging request at virtual address fee02f00 when write [fee02f00] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 4792 Comm: syz.1.263 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: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 : [<81490fb4>] lr : [<81490fa4>] psr: 60000013 sp : dfcadd30 ip : dfcadd30 fp : dfcadd54 r10: 82d30dfc r9 : 00000003 r8 : 8429f480 r7 : dfcadd90 r6 : 8429f480 r5 : 00000000 r4 : 00000000 r3 : fee02f00 r2 : 81e2dc88 r1 : 00000001 r0 : 81490c14 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 86555040 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 8429f480 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfcac000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Register r8 information: slab kmalloc-192 start 8429f480 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 0xdfcac000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Register r12 information: 2-page vmalloc region starting at 0xdfcac000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Process syz.1.263 (pid: 4792, stack limit = 0xdfcac000) Stack: (0xdfcadd30 to 0xdfcae000) dd20: 824d3e30 8429f480 dfcadd58 82bd8e44 dd40: 81e2e148 00000000 dfcadd8c dfcadd58 8148cb2c 81490e3c 20000300 00000000 dd60: 00000001 20000300 8429f480 b5403587 40946400 00000001 00000003 847c9880 dd80: dfcade4c dfcadd90 81488330 8148ca30 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00002f00 00000005 0000d09a ffffffff 00000003 fffffffe 20000004 ddc0: 00000003 00000ffe 7fffffff 0000000c 00000002 00000004 00000008 0000ffff dde0: 00000006 00000005 000007ff 00000830 00000008 00010000 00000009 00000800 de00: 00000101 00000002 00008001 00000007 00000003 00000004 00000005 0000070f de20: 00000000 99d35d2a 847c9880 83fc1680 8429f480 20000300 40946400 00000001 de40: dfcadf14 dfcade50 81489658 81488270 00000000 99d35d2a 00000000 00000000 de60: 8254880c dfcadea4 0000005f 84c78b68 00000064 8429f4b0 dfcadee4 dfcade88 de80: 80804edc 807fb20c 00000064 00000001 00000000 dfcadea4 861d3310 8343edd0 dea0: 00006400 0000000b dfcade98 00000000 00000000 99d35d2a dfcadfa4 dfcadec8 dec0: 80200bec 81b20654 83fc1680 40946400 20000300 81489304 00000000 83fc1681 dee0: 40946400 99d35d2a 83fc1680 00000000 83fc1681 40946400 20000300 83fc1680 df00: 00000003 847c9880 dfcadfa4 dfcadf18 805ba7e8 81489310 ecac8b10 847c9880 df20: dfcadf3c dfcadf30 81b546a0 81b5456c dfcadf54 dfcadf40 8025a7ac 8028e488 df40: dfcadfb0 40000000 dfcadf84 dfcadf58 80220bdc 8025a768 00000000 82a1eb0c df60: dfcadfb0 0013e9c0 ecac8b10 80220b30 00000000 99d35d2a dfcadfac 00000000 df80: 00000000 00346310 00000036 8020029c 847c9880 00000036 00000000 dfcadfa8 dfa0: 80200060 805ba5b0 00000000 00000000 00000003 40946400 20000300 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f1e0dc dfe0: 76f1de88 76f1de78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<81490e30>] (parport_attach) from [<8148cb2c>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e148 r4:82bd8e44 [<8148ca24>] (comedi_device_attach) from [<81488330>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:847c9880 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:8429f480 r4:20000300 [<81488264>] (do_devconfig_ioctl) from [<81489658>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000300 r5:8429f480 r4:83fc1680 [<81489304>] (comedi_unlocked_ioctl) from [<805ba7e8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81489304>] (comedi_unlocked_ioctl) from [<805ba7e8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81489304>] (comedi_unlocked_ioctl) from [<805ba7e8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81489304>] (comedi_unlocked_ioctl) from [<805ba7e8>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:847c9880 r9:00000003 r8:83fc1680 r7:20000300 r6:40946400 r5:83fc1681 r4:00000000 [<805ba5a4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfcadfa8 to 0xdfcadff0) dfa0: 00000000 00000000 00000003 40946400 20000300 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f1e0dc dfe0: 76f1de88 76f1de78 00018ebc 00130820 r10:00000036 r9:847c9880 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