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: 0 UID: 0 PID: 15603 Comm: syz.6.584 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 : [<813b8ba0>] lr : [<813b8b8c>] psr: 60000013 sp : e0341cb8 ip : e0341cb8 fp : e0341cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 842c30c0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 842c30c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85e84a40 DAC: fffffffd Register r0 information: slab kmalloc-192 start 842c30c0 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 842c30c0 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xe0340000 allocated at vhost_task_create+0xe4/0x134 kernel/vhost_task.c:145 Register r12 information: 2-page vmalloc region starting at 0xe0340000 allocated at vhost_task_create+0xe4/0x134 kernel/vhost_task.c:145 Process syz.6.584 (pid: 15603, stack limit = 0xe0340000) Stack: (0xe0341cb8 to 0xe0342000) 1ca0: 813b8b40 842c30c0 1cc0: 00004f27 00004f27 e0341cf4 e0341cd8 813b8878 813b8b4c 00004f27 80503b64 1ce0: 84ed0000 84ed0000 e0341d14 e0341cf8 813b8c38 813b882c 84ed0000 842c30c0 1d00: e0341da4 00004f27 e0341d54 e0341d18 813b8e2c 813b8bb8 829d0144 842c30c0 1d20: 00000000 00000000 842c30c0 829d0144 842c30c0 842c3104 e0341d90 842c30c0 1d40: 00000000 82b16f40 e0341d8c e0341d58 813a7d34 813b8d7c 200000c0 00000000 1d60: e0341d7c 200000c0 842c30c0 b5403587 200000c0 83ad2400 40946400 00000003 1d80: e0341e4c e0341d90 813a3880 813a7c38 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000003 00000004 00000001 0000000c 00000012 1dc0: 00000004 0000000d fffffffc 00000002 00000001 fffffffe 00000001 00000002 1de0: 00000101 00000004 00000009 00000003 0000352f 00000099 0000caa7 00000080 1e00: 20001e58 00000007 02000e67 0000003c 00000008 fffffffe 00000000 fffffff8 1e20: 00000000 41aa2e1f 00000000 864f1f00 842c30c0 200000c0 200000c0 83ad2400 1e40: e0341f14 e0341e50 813a484c 813a378c 00000000 00000000 00000000 41aa2e1f 1e60: 00000000 00000000 8247054c 0000005f 83bdc458 842c30f0 84114a74 83ad2400 1e80: e0341ee4 e0341e90 80797aa4 8078de08 00000064 00000001 00000000 e0341eac 1ea0: 84bc9190 83429198 00006400 0000000b e0341ea0 00000000 00000000 41aa2e1f 1ec0: 864f1f00 40946400 200000c0 200000c0 864f1f00 00000003 e0341ef4 e0341ee8 1ee0: 80797bc4 41aa2e1f e0341f14 40946400 00000000 864f1f01 200000c0 864f1f00 1f00: 00000003 83ad2400 e0341fa4 e0341f18 8056cdc8 813a427c ecac8b10 83ad2400 1f20: e0341f3c e0341f30 81a39db8 81a39c88 e0341f54 e0341f40 8025e490 8028ef6c 1f40: e0341fb0 40000000 e0341f84 e0341f58 802229ec 8025e44c 00000000 8281cddc 1f60: e0341fb0 0014c820 ecac8b10 80222940 00000000 41aa2e1f e0341fac 00000000 1f80: 00000000 002f6308 00000036 8020029c 83ad2400 00000036 00000000 e0341fa8 1fa0: 80200060 8056cca4 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f530bc 1fe0: 76f52ec0 76f52eb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b8b40>] (subdev_8255_io) from [<813b8878>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:842c30c0 r4:813b8b40 [<813b8820>] (subdev_8255_do_config) from [<813b8c38>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b8820>] (subdev_8255_do_config) from [<813b8c38>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84ed0000 [<813b8bac>] (subdev_8255_io_init) from [<813b8e2c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b8bac>] (subdev_8255_io_init) from [<813b8e2c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:e0341da4 r5:842c30c0 r4:84ed0000 [<813b8d70>] (dev_8255_attach) from [<813a7d34>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b16f40 r9:00000000 r8:842c30c0 r7:e0341d90 r6:842c3104 r5:842c30c0 r4:829d0144 [<813a7c2c>] (comedi_device_attach) from [<813a3880>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83ad2400 r7:200000c0 r6:b5403587 r5:842c30c0 r4:200000c0 [<813a3780>] (do_devconfig_ioctl) from [<813a484c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83ad2400 r7:200000c0 r6:200000c0 r5:842c30c0 r4:864f1f00 [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a4270>] (comedi_unlocked_ioctl) from [<8056cdc8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:83ad2400 r9:00000003 r8:864f1f00 r7:200000c0 r6:864f1f01 r5:00000000 r4:40946400 [<8056cc98>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0341fa8 to 0xe0341ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f530bc 1fe0: 76f52ec0 76f52eb0 0001948c 001322c0 r10:00000036 r9:83ad2400 r8:8020029c r7:00000036 r6:002f6308 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