8<--- cut here --- Unable to handle kernel paging request at virtual address fee09003 when write [fee09003] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 4020 Comm: syz.0.73 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 subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] PC is at subdev_8255_io+0x60/0x6c drivers/comedi/drivers/comedi_8255.c:43 LR is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] LR is at subdev_8255_io+0x4c/0x6c drivers/comedi/drivers/comedi_8255.c:43 pc : [<814684c8>] lr : [<814684b4>] psr: 60000013 sp : ea879cb8 ip : ea879cb8 fp : ea879cd4 r10: 00009000 r9 : 00000004 r8 : ea879da4 r7 : 00000000 r6 : 0000009b r5 : 8334b840 r4 : 00009003 r3 : 0000009b r2 : fee09003 r1 : 00000001 r0 : 8334b840 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 86168c80 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8334b840 pointer offset 0 size 192 Register r1 information: non-paged memory Register r2 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1048 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 8334b840 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: NULL pointer Register r8 information: 2-page vmalloc region starting at 0xea878000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xea878000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r12 information: 2-page vmalloc region starting at 0xea878000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Process syz.0.73 (pid: 4020, stack limit = 0xea878000) Stack: (0xea879cb8 to 0xea87a000) 9ca0: 81468468 00009000 9cc0: 8334b840 00000000 ea879cf4 ea879cd8 814681a4 81468474 00009000 80532a2c 9ce0: 85121000 85121000 ea879d14 ea879cf8 8146855c 81468158 8334b840 00000000 9d00: 85121000 00000000 ea879d54 ea879d18 8146870c 814684e0 ffffffff 00000004 9d20: 82a20900 00000000 00000000 82bd2a24 8334b840 00000000 ea879d90 8334b840 9d40: 00000000 82d29754 ea879d8c ea879d58 814570b0 814686a4 40946400 00000000 9d60: ea879d7c 20000300 8334b840 b5403587 40946400 00000001 00000003 851d0c80 9d80: ea879e4c ea879d90 814528bc 81456fb4 35353238 00000000 00000000 00000000 9da0: 00000000 00009000 00000009 00000a1a 00000004 00000004 0800afa3 00000004 9dc0: 00000008 00005857 00000002 00000007 00000009 00000001 00000005 00000006 9de0: 00000501 00000000 00007fff 00000002 0000000a 00000008 0000caa2 00001003 9e00: 20001e5b 02000003 00000e69 00000002 0000004d 00004086 00000000 00000004 9e20: 00000000 21b04519 00000000 83885000 8334b840 20000300 40946400 00000001 9e40: ea879f14 ea879e50 81453be0 814527f4 00000000 21b04519 00000000 00000000 9e60: 82531804 ea879ea4 0000005f 84662058 00000064 8334b870 ea879ee4 ea879e88 9e80: 807ea79c 807e0ab0 00000064 00000001 00000000 ea879ea4 830ebe50 834f0660 9ea0: 00006400 0000000b ea879e98 00000000 00000000 21b04519 00000000 83885000 9ec0: 40946400 20000300 20000300 83885000 00000003 851d0c80 ea879ef4 ea879ee8 9ee0: 807ea8d0 21b04519 ea879f14 00000000 83885001 40946400 20000300 83885000 9f00: 00000003 851d0c80 ea879fa4 ea879f18 805a20fc 81453898 ecac8b10 851d0c80 9f20: ea879f3c ea879f30 81b1ad14 81b1abe0 ea879f54 ea879f40 8025a6ac 8028e294 9f40: ea879fb0 40000000 ea879f84 ea879f58 80220be0 8025a668 00000000 82a1c63c 9f60: ea879fb0 0013e9b0 ecac8b10 80220b34 00000000 21b04519 ea879fac 00000000 9f80: 00000000 00346310 00000036 8020029c 851d0c80 00000036 00000000 ea879fa8 9fa0: 80200060 805a1ec4 00000000 00000000 00000003 40946400 20000300 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76ff70dc 9fe0: 76ff6e88 76ff6e78 00018ebc 00130810 60000010 00000003 00000000 00000000 Call trace: [<81468468>] (subdev_8255_io) from [<814681a4>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:8334b840 r5:00009000 r4:81468468 [<8146814c>] (subdev_8255_do_config) from [<8146855c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8146814c>] (subdev_8255_do_config) from [<8146855c>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85121000 [<814684d4>] (subdev_8255_io_init) from [<8146870c>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814684d4>] (subdev_8255_io_init) from [<8146870c>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:85121000 r5:00000000 r4:8334b840 [<81468698>] (dev_8255_attach) from [<814570b0>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d29754 r9:00000000 r8:8334b840 r7:ea879d90 r6:00000000 r5:8334b840 r4:82bd2a24 [<81456fa8>] (comedi_device_attach) from [<814528bc>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:851d0c80 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:8334b840 r4:20000300 [<814527e8>] (do_devconfig_ioctl) from [<81453be0>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000300 r5:8334b840 r4:83885000 [<8145388c>] (comedi_unlocked_ioctl) from [<805a20fc>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8145388c>] (comedi_unlocked_ioctl) from [<805a20fc>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8145388c>] (comedi_unlocked_ioctl) from [<805a20fc>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8145388c>] (comedi_unlocked_ioctl) from [<805a20fc>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:851d0c80 r9:00000003 r8:83885000 r7:20000300 r6:40946400 r5:83885001 r4:00000000 [<805a1eb8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea879fa8 to 0xea879ff0) 9fa0: 00000000 00000000 00000003 40946400 20000300 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76ff70dc 9fe0: 76ff6e88 76ff6e78 00018ebc 00130810 r10:00000036 r9:851d0c80 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e6ef3076 e0842002 e7f32052 e2422612 (e5c23000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef3076 uxtb r3, r6 4: e0842002 add r2, r4, r2 8: e7f32052 ubfx r2, r2, #0, #20 c: e2422612 sub r2, r2, #18874368 @ 0x1200000 * 10: e5c23000 strb r3, [r2] <-- trapping instruction