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: 1 UID: 0 PID: 5382 Comm: syz.0.211 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: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 : [<81459abc>] lr : [<81459aac>] psr: 60000013 sp : ea779d30 ip : ea779d30 fp : ea779d54 r10: 82d2cdc4 r9 : 00000003 r8 : 8334ca80 r7 : ea779d90 r6 : 8334ca80 r5 : 00000000 r4 : 00000000 r3 : fee00400 r2 : 81e277a8 r1 : 00000001 r0 : 8145971c Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8330a300 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 8334ca80 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xea778000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Register r8 information: slab kmalloc-192 start 8334ca80 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 0xea778000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Register r12 information: 2-page vmalloc region starting at 0xea778000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Process syz.0.211 (pid: 5382, stack limit = 0xea778000) Stack: (0xea779d30 to 0xea77a000) 9d20: ffffffff 00000004 00000000 82bd2c7c 9d40: 81e27c68 00000000 ea779d8c ea779d58 81455620 81459944 40946400 00000000 9d60: ea779d7c 20000140 8334ca80 b5403587 40946400 00000001 00000004 83fa4b00 9d80: ea779e4c ea779d90 81450e2c 81455524 656d6f63 705f6964 6f707261 00007472 9da0: 00000000 00000400 00000000 7fffffff 000084e1 0000002f 00002006 00000006 9dc0: 00000008 000a0ffa 00000000 00000007 00000002 00001003 01000004 0000000f 9de0: 00010000 ffffffa8 7ffbfffd 000001ff 0000ecd0 00000010 0003fffe 00000008 9e00: 00000007 0000746f 00000004 00000005 00000408 00000004 00000000 00007ffd 9e20: 00000000 ff1786e5 00000000 83317f80 8334ca80 20000140 40946400 00000001 9e40: ea779f14 ea779e50 81452150 81450d64 00000000 ff1786e5 00000000 00000000 9e60: 82531804 ea779ea4 0000005f 841e1dd8 00000064 8334cab0 ea779ee4 ea779e88 9e80: 807ea1fc 807e0510 00000064 00000001 00000000 ea779ea4 830e9190 834d5d48 9ea0: 00006400 0000000b ea779e98 00000000 00000000 ff1786e5 ea779fa4 ea779ec8 9ec0: 80200bec 81ae3dc8 83317f80 40946400 20000140 81451dfc 00000000 83317f81 9ee0: 40946400 ff1786e5 83317f80 00000000 83317f81 40946400 20000140 83317f80 9f00: 00000004 83fa4b00 ea779fa4 ea779f18 805a1b84 81451e08 ecac8b10 83fa4b00 9f20: ea779f3c ea779f30 81b17c14 81b17ae0 ea779f54 ea779f40 8025a6bc 8028e2a4 9f40: ea779fb0 40000000 ea779f84 ea779f58 80220be0 8025a678 00000000 82a1c63c 9f60: ea779fb0 0013e9b0 ecac8b10 80220b34 00000000 ff1786e5 ea779fac 00000000 9f80: 00000000 00346310 00000036 8020029c 83fa4b00 00000036 00000000 ea779fa8 9fa0: 80200060 805a194c 00000000 00000000 00000004 40946400 20000140 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fd30dc 9fe0: 76fd2e88 76fd2e78 00018ebc 00130810 60000010 00000004 00000000 00000000 Call trace: [<81459938>] (parport_attach) from [<81455620>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e27c68 r4:82bd2c7c [<81455518>] (comedi_device_attach) from [<81450e2c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:83fa4b00 r9:00000004 r8:00000001 r7:40946400 r6:b5403587 r5:8334ca80 r4:20000140 [<81450d58>] (do_devconfig_ioctl) from [<81452150>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000140 r5:8334ca80 r4:83317f80 [<81451dfc>] (comedi_unlocked_ioctl) from [<805a1b84>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81451dfc>] (comedi_unlocked_ioctl) from [<805a1b84>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81451dfc>] (comedi_unlocked_ioctl) from [<805a1b84>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81451dfc>] (comedi_unlocked_ioctl) from [<805a1b84>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83fa4b00 r9:00000004 r8:83317f80 r7:20000140 r6:40946400 r5:83317f81 r4:00000000 [<805a1940>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea779fa8 to 0xea779ff0) 9fa0: 00000000 00000000 00000004 40946400 20000140 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fd30dc 9fe0: 76fd2e88 76fd2e78 00018ebc 00130810 r10:00000036 r9:83fa4b00 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