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: 1 UID: 0 PID: 6719 Comm: syz.0.822 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 : [<81466a50>] lr : [<81466a3c>] psr: 60000013 sp : dfe81cb8 ip : dfe81cb8 fp : dfe81cd4 r10: 00009000 r9 : 00000004 r8 : dfe81da4 r7 : 00000000 r6 : 0000009b r5 : 845fef00 r4 : 00009003 r3 : 0000009b r2 : fee09003 r1 : 00000001 r0 : 845fef00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86a33600 DAC: 00000000 Register r0 information: slab kmalloc-192 start 845fef00 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 845fef00 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 0xdfe80000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfe80000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Register r12 information: 2-page vmalloc region starting at 0xdfe80000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Process syz.0.822 (pid: 6719, stack limit = 0xdfe80000) Stack: (0xdfe81cb8 to 0xdfe82000) 1ca0: 814669f0 00009000 1cc0: 845fef00 00000000 dfe81cf4 dfe81cd8 8146672c 814669fc 00009000 80532538 1ce0: 85efb180 85efb180 dfe81d14 dfe81cf8 81466ae4 814666e0 845fef00 00000000 1d00: 85efb180 00000000 dfe81d54 dfe81d18 81466c94 81466a68 ffffffff 00000004 1d20: 82a20900 00000000 00000000 82bd3438 845fef00 00000000 dfe81d90 845fef00 1d40: 00000000 82d2cdc4 dfe81d8c dfe81d58 81455620 81466c2c 40946400 00000000 1d60: dfe81d7c 20000140 845fef00 b5403587 40946400 00000001 00000007 83fd7080 1d80: dfe81e4c dfe81d90 81450e2c 81455524 35353238 00000000 00000000 00000000 1da0: 00000000 00009000 00000000 00000a1a 00000004 00000004 0800afa3 00000004 1dc0: 00000008 00005857 00000002 00000007 00000009 00000001 00000005 00000006 1de0: 00000501 00000000 00000004 00000002 0000000a 00000008 0000caa2 00001003 1e00: 20001e5b 02000003 00000e69 00000002 00000004 00004086 00000000 00000004 1e20: 00000000 1573147a 00000000 838b4280 845fef00 20000140 40946400 00000001 1e40: dfe81f14 dfe81e50 81452150 81450d64 00000000 1573147a 00000000 00000000 1e60: 82531804 dfe81ea4 0000005f 84125c00 00000064 845fef30 dfe81ee4 dfe81e88 1e80: 807ea1fc 807e0510 00000064 00000001 00000000 dfe81ea4 830e96d0 834335d8 1ea0: 00006400 0000000b dfe81e98 00000000 00000000 1573147a 00000000 838b4280 1ec0: 40946400 20000140 20000140 838b4280 00000007 83fd7080 dfe81ef4 dfe81ee8 1ee0: 807ea330 1573147a dfe81f14 00000000 838b4281 40946400 20000140 838b4280 1f00: 00000007 83fd7080 dfe81fa4 dfe81f18 805a1b84 81451e08 ecac8b10 83fd7080 1f20: dfe81f3c dfe81f30 81b17c14 81b17ae0 dfe81f54 dfe81f40 8025a6bc 8028e2a4 1f40: dfe81fb0 40000000 dfe81f84 dfe81f58 80220be0 8025a678 00000000 82a1c63c 1f60: dfe81fb0 0013e9b0 ecac8b10 80220b34 00000000 1573147a dfe81fac 00000000 1f80: 00000000 00346450 00000036 8020029c 83fd7080 00000036 00000000 dfe81fa8 1fa0: 80200060 805a194c 00000000 00000000 00000007 40946400 20000140 00000000 1fc0: 00000000 00000000 00346450 00000036 00346418 00000000 00000001 76ed70dc 1fe0: 76ed6e88 76ed6e78 00018ebc 00130810 60000010 00000007 00000000 00000000 Call trace: [<814669f0>] (subdev_8255_io) from [<8146672c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:845fef00 r5:00009000 r4:814669f0 [<814666d4>] (subdev_8255_do_config) from [<81466ae4>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814666d4>] (subdev_8255_do_config) from [<81466ae4>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85efb180 [<81466a5c>] (subdev_8255_io_init) from [<81466c94>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<81466a5c>] (subdev_8255_io_init) from [<81466c94>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:85efb180 r5:00000000 r4:845fef00 [<81466c20>] (dev_8255_attach) from [<81455620>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d2cdc4 r9:00000000 r8:845fef00 r7:dfe81d90 r6:00000000 r5:845fef00 r4:82bd3438 [<81455518>] (comedi_device_attach) from [<81450e2c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:83fd7080 r9:00000007 r8:00000001 r7:40946400 r6:b5403587 r5:845fef00 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 r5:845fef00 r4:838b4280 [<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) r10:83fd7080 r9:00000007 r8:838b4280 r7:20000140 r6:40946400 r5:838b4281 r4:00000000 [<805a1940>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfe81fa8 to 0xdfe81ff0) 1fa0: 00000000 00000000 00000007 40946400 20000140 00000000 1fc0: 00000000 00000000 00346450 00000036 00346418 00000000 00000001 76ed70dc 1fe0: 76ed6e88 76ed6e78 00018ebc 00130810 r10:00000036 r9:83fd7080 r8:8020029c r7:00000036 r6:00346450 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