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: 13141 Comm: syz.4.1328 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 : [<81468918>] lr : [<81468904>] psr: 60000013 sp : dfbd9cb8 ip : dfbd9cb8 fp : dfbd9cd4 r10: 00009000 r9 : 00000004 r8 : dfbd9da4 r7 : 00000000 r6 : 0000009b r5 : 8301a480 r4 : 00009003 r3 : 0000009b r2 : fee09003 r1 : 00000001 r0 : 8301a480 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 861ae880 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8301a480 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 8301a480 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 0xdfbd8000 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 0xdfbd8000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r12 information: 2-page vmalloc region starting at 0xdfbd8000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Process syz.4.1328 (pid: 13141, stack limit = 0xdfbd8000) Stack: (0xdfbd9cb8 to 0xdfbda000) 9ca0: 814688b8 00009000 9cc0: 8301a480 00000000 dfbd9cf4 dfbd9cd8 814685f4 814688c4 00009000 805329dc 9ce0: 870e0000 870e0000 dfbd9d14 dfbd9cf8 814689ac 814685a8 8301a480 00000000 9d00: 870e0000 00000000 dfbd9d54 dfbd9d18 81468b5c 81468930 ffffffff 00000004 9d20: 82a20900 00000000 00000000 82bd2b24 8301a480 00000000 dfbd9d90 8301a480 9d40: 00000000 82d29754 dfbd9d8c dfbd9d58 81457500 81468af4 40946400 00000000 9d60: dfbd9d7c 20000140 8301a480 b5403587 40946400 00000001 00000003 85102580 9d80: dfbd9e4c dfbd9d90 81452d0c 81457404 35353238 00000000 00000000 00000000 9da0: 00000000 00009000 000007db 00000a1a 00000004 00000004 0800afa3 00000004 9dc0: 00000008 00005857 00000002 00000009 00000009 00000001 00000005 00000006 9de0: 00000501 00000000 00000004 00000002 00000007 00400008 0000caa4 00001003 9e00: 20001e5b 02000003 00000e69 00000002 00000004 00004086 00000000 00000004 9e20: 00000000 6103e8b2 00000000 865bbb80 8301a480 20000140 40946400 00000001 9e40: dfbd9f14 dfbd9e50 81454030 81452c44 00000000 6103e8b2 00000000 00000000 9e60: 82531804 dfbd9ea4 0000005f 8418af18 00000064 8301a4b0 dfbd9ee4 dfbd9e88 9e80: 807eaa84 807e0d98 00000064 00000001 00000000 dfbd9ea4 867ee0d0 834243b8 9ea0: 00006400 0000000b dfbd9e98 00000000 00000000 6103e8b2 00000000 865bbb80 9ec0: 40946400 20000140 20000140 865bbb80 00000003 85102580 dfbd9ef4 dfbd9ee8 9ee0: 807eabb8 6103e8b2 dfbd9f14 00000000 865bbb81 40946400 20000140 865bbb80 9f00: 00000003 85102580 dfbd9fa4 dfbd9f18 805a2310 81453ce8 ecac8b10 85102580 9f20: dfbd9f3c dfbd9f30 81b1b714 81b1b5e0 dfbd9f54 dfbd9f40 8025a6ac 8028e2e4 9f40: dfbd9fb0 40000000 dfbd9f84 dfbd9f58 80220be0 8025a668 00000000 82a1c63c 9f60: dfbd9fb0 0013e9b0 ecac8b10 80220b34 00000000 6103e8b2 dfbd9fac 00000000 9f80: 00000000 00346310 00000036 8020029c 85102580 00000036 00000000 dfbd9fa8 9fa0: 80200060 805a20d8 00000000 00000000 00000003 40946400 20000140 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fe00dc 9fe0: 76fdfe88 76fdfe78 00018ebc 00130810 60000010 00000003 00000000 00000000 Call trace: [<814688b8>] (subdev_8255_io) from [<814685f4>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:8301a480 r5:00009000 r4:814688b8 [<8146859c>] (subdev_8255_do_config) from [<814689ac>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8146859c>] (subdev_8255_do_config) from [<814689ac>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:870e0000 [<81468924>] (subdev_8255_io_init) from [<81468b5c>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<81468924>] (subdev_8255_io_init) from [<81468b5c>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:870e0000 r5:00000000 r4:8301a480 [<81468ae8>] (dev_8255_attach) from [<81457500>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d29754 r9:00000000 r8:8301a480 r7:dfbd9d90 r6:00000000 r5:8301a480 r4:82bd2b24 [<814573f8>] (comedi_device_attach) from [<81452d0c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:85102580 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:8301a480 r4:20000140 [<81452c38>] (do_devconfig_ioctl) from [<81454030>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000140 r5:8301a480 r4:865bbb80 [<81453cdc>] (comedi_unlocked_ioctl) from [<805a2310>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81453cdc>] (comedi_unlocked_ioctl) from [<805a2310>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81453cdc>] (comedi_unlocked_ioctl) from [<805a2310>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81453cdc>] (comedi_unlocked_ioctl) from [<805a2310>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:85102580 r9:00000003 r8:865bbb80 r7:20000140 r6:40946400 r5:865bbb81 r4:00000000 [<805a20cc>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbd9fa8 to 0xdfbd9ff0) 9fa0: 00000000 00000000 00000003 40946400 20000140 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fe00dc 9fe0: 76fdfe88 76fdfe78 00018ebc 00130810 r10:00000036 r9:85102580 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