8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2a when write [fee04f2a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 16896 Comm: syz.7.2723 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 : [<8143e3b0>] lr : [<8143e39c>] psr: 60000013 sp : dfb41cb8 ip : dfb41cb8 fp : dfb41cd4 r10: 00000000 r9 : 00000084 r8 : dfb41da4 r7 : 00004f27 r6 : 0000009b r5 : 83019f00 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 83019f00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8bd6e300 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83019f00 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:1055 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 83019f00 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xdfb40000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdfb40000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdfb40000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.7.2723 (pid: 16896, stack limit = 0xdfb40000) Stack: (0xdfb41cb8 to 0xdfb42000) 1ca0: 8143e350 00004f27 1cc0: 83019f00 00004f27 dfb41cf4 dfb41cd8 8143e08c 8143e35c 00004f27 80522770 1ce0: 8be6e000 8be6e000 dfb41d14 dfb41cf8 8143e444 8143e040 83019f00 00000000 1d00: 8be6e000 00004f27 dfb41d54 dfb41d18 8143e5f4 8143e3c8 82b09824 840a7f80 1d20: 828217c0 00000000 00000000 829d6e04 83019f00 00000000 dfb41d90 83019f00 1d40: 00000000 82b2efdc dfb41d8c dfb41d58 8142cf2c 8143e58c 40946400 00000000 1d60: dfb41d7c 200000c0 83019f00 b5403587 40946400 00000000 00000003 84628000 1d80: dfb41e4c dfb41d90 81428740 8142ce2c 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000002 00000401 00000003 00000cc7 00000fff 1dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 1de0: 0000e1cb ffffffc0 00000004 00000003 00000004 00000002 fffffff9 00000000 1e00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 0000000a dffffffa 1e20: 00000000 5da46ac3 00000000 85aa5d80 83019f00 200000c0 40946400 00000000 1e40: dfb41f14 dfb41e50 81429a64 81428678 00000000 5da46ac3 00000000 00000000 1e60: 824b857c dfb41ea4 0000005f 843257f8 00000064 83019f30 dfb41ee4 dfb41e88 1e80: 807cd9ac 807c3d84 00000064 00000001 00000000 dfb41ea4 866bd910 8343f440 1ea0: 00006400 0000000b dfb41e98 00000000 00000000 5da46ac3 00000000 85aa5d80 1ec0: 40946400 200000c0 200000c0 85aa5d80 00000003 84628000 dfb41ef4 dfb41ee8 1ee0: 807cdadc 5da46ac3 dfb41f14 00000000 85aa5d81 40946400 200000c0 85aa5d80 1f00: 00000003 84628000 dfb41fa4 dfb41f18 8058f8c4 8142971c ecac8b10 84628000 1f20: dfb41f3c dfb41f30 81ae1874 81ae1740 dfb41f54 dfb41f40 8025a85c 8028c340 1f40: dfb41fb0 40000000 dfb41f84 dfb41f58 80220bf8 8025a818 00000000 8281d2bc 1f60: dfb41fb0 0013e290 ecac8b10 80220b4c 00000000 5da46ac3 dfb41fac 00000000 1f80: 00000000 00346310 00000036 8020029c 84628000 00000036 00000000 dfb41fa8 1fa0: 80200060 8058f68c 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fad0dc 1fe0: 76face88 76face78 00018ba0 001300f0 60000010 00000003 00000000 00000000 Call trace: [<8143e350>] (subdev_8255_io) from [<8143e08c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:83019f00 r5:00004f27 r4:8143e350 [<8143e034>] (subdev_8255_do_config) from [<8143e444>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8143e034>] (subdev_8255_do_config) from [<8143e444>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:8be6e000 [<8143e3bc>] (subdev_8255_io_init) from [<8143e5f4>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8143e3bc>] (subdev_8255_io_init) from [<8143e5f4>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:8be6e000 r5:00000000 r4:83019f00 [<8143e580>] (dev_8255_attach) from [<8142cf2c>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2efdc r9:00000000 r8:83019f00 r7:dfb41d90 r6:00000000 r5:83019f00 r4:829d6e04 [<8142ce20>] (comedi_device_attach) from [<81428740>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:84628000 r9:00000003 r8:00000000 r7:40946400 r6:b5403587 r5:83019f00 r4:200000c0 [<8142866c>] (do_devconfig_ioctl) from [<81429a64>] (comedi_unlocked_ioctl+0x354/0x1dbc drivers/comedi/comedi_fops.c:2300) r8:00000000 r7:40946400 r6:200000c0 r5:83019f00 r4:85aa5d80 [<81429710>] (comedi_unlocked_ioctl) from [<8058f8c4>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81429710>] (comedi_unlocked_ioctl) from [<8058f8c4>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81429710>] (comedi_unlocked_ioctl) from [<8058f8c4>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81429710>] (comedi_unlocked_ioctl) from [<8058f8c4>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:84628000 r9:00000003 r8:85aa5d80 r7:200000c0 r6:40946400 r5:85aa5d81 r4:00000000 [<8058f680>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb41fa8 to 0xdfb41ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fad0dc 1fe0: 76face88 76face78 00018ba0 001300f0 r10:00000036 r9:84628000 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