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: 5919 Comm: syz.0.444 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 : [<81436260>] lr : [<8143624c>] psr: 60000013 sp : dfbb9cb8 ip : dfbb9cb8 fp : dfbb9cd4 r10: 00000000 r9 : 00000084 r8 : dfbb9da4 r7 : 00004f27 r6 : 0000009b r5 : 8385de40 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8385de40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85b70f40 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8385de40 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 8385de40 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 0xdfbb8000 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 0xdfbb8000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdfbb8000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.0.444 (pid: 5919, stack limit = 0xdfbb8000) Stack: (0xdfbb9cb8 to 0xdfbba000) 9ca0: 81436200 00004f27 9cc0: 8385de40 00004f27 dfbb9cf4 dfbb9cd8 81435f3c 8143620c 00004f27 805223ec 9ce0: 866d5000 866d5000 dfbb9d14 dfbb9cf8 814362f4 81435ef0 8385de40 00000000 9d00: 866d5000 00004f27 dfbb9d54 dfbb9d18 814364a4 81436278 82b16724 838a5800 9d20: 82821780 00000000 00000000 829d6504 8385de40 00000000 dfbb9d90 8385de40 9d40: 00000000 82b2df9c dfbb9d8c dfbb9d58 81424e90 8143643c 40946400 00000000 9d60: dfbb9d7c 200000c0 8385de40 b5403587 40946400 8408bc00 00000003 8385de70 9d80: dfbb9e4c dfbb9d90 814207c8 81424d90 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff 9dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 9de0: 0000e1cb 00000006 00000004 00000003 00000395 80000089 fffffffd 00000000 9e00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 08000000 dffffffa 9e20: 00000000 6139b836 00000000 838def00 8385de40 200000c0 40946400 8408bc00 9e40: dfbb9f14 dfbb9e50 81421348 81420700 00000000 6139b836 00000000 00000000 9e60: 824b557c dfbb9ea4 0000005f 844ab210 00000064 8423524c dfbb9ee4 dfbb9e88 9e80: 807cb7cc 807c1ba4 00000064 00000001 00000000 dfbb9ea4 830cd550 83429550 9ea0: 00006400 0000000b dfbb9e98 00000000 00000000 6139b836 00000000 838def00 9ec0: 40946400 200000c0 200000c0 838def00 00000006 8408bc00 dfbb9ef4 dfbb9ee8 9ee0: 807cb8fc 6139b836 dfbb9f14 00000000 838def01 40946400 200000c0 838def00 9f00: 00000006 8408bc00 dfbb9fa4 dfbb9f18 8058f558 81421250 ecac8b10 8408bc00 9f20: dfbb9f3c dfbb9f30 81ad9374 81ad9240 dfbb9f54 dfbb9f40 8025a85c 8028bff0 9f40: dfbb9fb0 40000000 dfbb9f84 dfbb9f58 80220bf8 8025a818 00000000 8281d27c 9f60: dfbb9fb0 0013ddc0 ecac8b10 80220b4c 00000000 6139b836 dfbb9fac 00000000 9f80: 00000000 00346310 00000036 8020029c 8408bc00 00000036 00000000 dfbb9fa8 9fa0: 80200060 8058f320 00000000 00000000 00000006 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f170dc 9fe0: 76f16e88 76f16e78 00018734 0012fc20 60000010 00000006 00000000 00000000 Call trace: [<81436200>] (subdev_8255_io) from [<81435f3c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:8385de40 r5:00004f27 r4:81436200 [<81435ee4>] (subdev_8255_do_config) from [<814362f4>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81435ee4>] (subdev_8255_do_config) from [<814362f4>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:866d5000 [<8143626c>] (subdev_8255_io_init) from [<814364a4>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8143626c>] (subdev_8255_io_init) from [<814364a4>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:866d5000 r5:00000000 r4:8385de40 [<81436430>] (dev_8255_attach) from [<81424e90>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2df9c r9:00000000 r8:8385de40 r7:dfbb9d90 r6:00000000 r5:8385de40 r4:829d6504 [<81424d84>] (comedi_device_attach) from [<814207c8>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:8385de70 r9:00000003 r8:8408bc00 r7:40946400 r6:b5403587 r5:8385de40 r4:200000c0 [<814206f4>] (do_devconfig_ioctl) from [<81421348>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:8408bc00 r7:40946400 r6:200000c0 r5:8385de40 r4:838def00 [<81421244>] (comedi_unlocked_ioctl) from [<8058f558>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81421244>] (comedi_unlocked_ioctl) from [<8058f558>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81421244>] (comedi_unlocked_ioctl) from [<8058f558>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81421244>] (comedi_unlocked_ioctl) from [<8058f558>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8408bc00 r9:00000006 r8:838def00 r7:200000c0 r6:40946400 r5:838def01 r4:00000000 [<8058f314>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbb9fa8 to 0xdfbb9ff0) 9fa0: 00000000 00000000 00000006 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f170dc 9fe0: 76f16e88 76f16e78 00018734 0012fc20 r10:00000036 r9:8408bc00 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