8<--- cut here --- Unable to handle kernel paging request at virtual address fee00144 when write [fee00144] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 21398 Comm: syz.4.2975 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 : [<81493794>] lr : [<81493784>] psr: 60000013 sp : e0205d30 ip : e0205d30 fp : e0205d54 r10: 82d30dfc r9 : 00000003 r8 : 831d2000 r7 : e0205d90 r6 : 831d2000 r5 : 00000000 r4 : 00000000 r3 : fee00144 r2 : 81e2dee8 r1 : 00000001 r0 : 814933f4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 879ff3c0 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 831d2000 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xe0204000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r8 information: slab kmalloc-192 start 831d2000 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 0xe0204000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r12 information: 2-page vmalloc region starting at 0xe0204000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Process syz.4.2975 (pid: 21398, stack limit = 0xe0204000) Stack: (0xe0205d30 to 0xe0206000) 5d20: 824d49b8 831d2000 82bd8ea0 82bd8ea0 5d40: 81e2e3a8 00000000 e0205d8c e0205d58 8148f310 8149361c 40946400 00000000 5d60: e0205d7c 200003c0 831d2000 b5403587 40946400 00000002 00000003 87a38000 5d80: e0205e4c e0205d90 8148ab14 8148f214 656d6f63 705f6964 6f707261 00007472 5da0: 00000000 00000144 fffffffc 0001000c 00000b35 00000000 00000004 00007fff 5dc0: 00000006 00000007 00000064 02000004 0000000f 00000005 00000009 000004ce 5de0: 00008e96 7fffffff 000080ed 00000005 00000009 00000001 00080000 00000008 5e00: 00000009 00000009 00000009 000000af 00000009 00000283 00000005 0000e43f 5e20: 00000000 48168bc8 00000000 87539e80 831d2000 200003c0 40946400 00000002 5e40: e0205f14 e0205e50 8148be3c 8148aa54 00000000 48168bc8 00000000 00000000 5e60: 8254980c e0205ea4 0000005f 844e32c8 00000064 831d2030 e0205ee4 e0205e88 5e80: 80806188 807fc404 00000064 00000001 00000000 e0205ea4 86f99410 835bc198 5ea0: 00006400 0000000b e0205e98 00000000 00000000 48168bc8 80357e30 87539e80 5ec0: 40946400 200003c0 200003c0 87539e80 00000003 87a38000 e0205ef4 e0205ee8 5ee0: 808062bc 48168bc8 e0205f14 00000000 87539e81 40946400 200003c0 87539e80 5f00: 00000003 87a38000 e0205fa4 e0205f18 805bab28 8148baf4 ecac8b10 87a38000 5f20: e0205f3c e0205f30 81b58240 81b5810c e0205f54 e0205f40 8025a7a8 8028e490 5f40: e0205fb0 40000000 e0205f84 e0205f58 80220bdc 8025a764 00000000 82a1eb0c 5f60: e0205fb0 0013e9c0 ecac8b10 80220b30 00000000 48168bc8 e0205fac 00000000 5f80: 00000000 00356310 00000036 8020029c 87a38000 00000036 00000000 e0205fa8 5fa0: 80200060 805ba8f0 00000000 00000000 00000003 40946400 200003c0 00000000 5fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f450dc 5fe0: 76f44e88 76f44e78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<81493610>] (parport_attach) from [<8148f310>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e3a8 r4:82bd8ea0 [<8148f208>] (comedi_device_attach) from [<8148ab14>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:87a38000 r9:00000003 r8:00000002 r7:40946400 r6:b5403587 r5:831d2000 r4:200003c0 [<8148aa48>] (do_devconfig_ioctl) from [<8148be3c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000002 r7:40946400 r6:200003c0 r5:831d2000 r4:87539e80 [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:87a38000 r9:00000003 r8:87539e80 r7:200003c0 r6:40946400 r5:87539e81 r4:00000000 [<805ba8e4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0205fa8 to 0xe0205ff0) 5fa0: 00000000 00000000 00000003 40946400 200003c0 00000000 5fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f450dc 5fe0: 76f44e88 76f44e78 00018ebc 00130820 r10:00000036 r9:87a38000 r8:8020029c r7:00000036 r6:00356310 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