8<--- cut here --- Unable to handle kernel paging request at virtual address fee0f003 when write [fee0f003] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 20802 Comm: syz.0.5343 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [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 : [<814e2414>] lr : [<814e2400>] psr: 60000113 sp : ea541cb8 ip : ea541cb8 fp : ea541cd4 r10: 0000f000 r9 : 00000004 r8 : ea541da4 r7 : 00000000 r6 : 0000009b r5 : 831e9480 r4 : 0000f003 r3 : 0000009b r2 : fee0f003 r1 : 00000001 r0 : 831e9480 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 863e08c0 DAC: 00000000 Register r0 information: slab kmalloc-192 start 831e9480 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 831e9480 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 0xea540000 allocated at kernel_clone+0xc4/0x440 kernel/fork.c:2771 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xea540000 allocated at kernel_clone+0xc4/0x440 kernel/fork.c:2771 Register r12 information: 2-page vmalloc region starting at 0xea540000 allocated at kernel_clone+0xc4/0x440 kernel/fork.c:2771 Process syz.0.5343 (pid: 20802, stack limit = 0xea540000) Stack: (0xea541cb8 to 0xea542000) 1ca0: 814e23b4 0000f000 1cc0: 831e9480 00000000 ea541cf4 ea541cd8 814e20f0 814e23c0 0000f000 805588c0 1ce0: 89b74000 89b74000 ea541d14 ea541cf8 814e24a8 814e20a4 831e9480 00000000 1d00: 89b74000 00000000 ea541d54 ea541d18 814e2658 814e242c ffffffff 00000004 1d20: 82a1e300 00000000 00000000 82bd8a3c 831e9480 00000000 ea541d90 831e9480 1d40: 00000000 82d307a0 ea541d8c ea541d58 814d0fe0 814e25f0 40946400 00000000 1d60: ea541d7c 20000000 831e9480 b5403587 40946400 00000001 00000003 840da580 1d80: ea541e4c ea541d90 814cc7e4 814d0ee4 35353238 00000000 00000000 00000000 1da0: 00000000 0000f000 00000006 00000002 0000000c 00090000 00000009 00040000 1dc0: 0000088f 00280ffa fffffdfc 00000005 00000008 00001030 01000008 00000030 1de0: 40000009 fff7ffa6 000003fb 00000912 fffffffe 00000003 00000009 0000000c 1e00: 00008001 00000001 00000200 0000ffff 00400018 00000082 02000006 00000005 1e20: 00000000 5239c1e3 00000000 89c8ef80 831e9480 20000000 40946400 00000001 1e40: ea541f14 ea541e50 814cdb0c 814cc724 ea541e4c 5239c1e3 00000000 00000000 1e60: 8252884c ea541ea4 0000005f 8416f850 00000064 831e94b0 ea541ee4 ea541e88 1e80: 80828cf0 8081f07c 00000064 00000001 00000000 ea541ea4 83fadd10 8343c440 1ea0: 00006400 0000000b ea541e98 00000000 ea541d38 5239c1e3 8035beb0 89c8ef80 1ec0: 40946400 20000000 20000000 89c8ef80 00000003 840da580 ea541ef4 ea541ee8 1ee0: 80828e24 5239c1e3 ea541f14 00000000 89c8ef81 40946400 20000000 89c8ef80 1f00: 00000003 840da580 ea541fa4 ea541f18 805d0f9c 814cd7c4 ecac8b10 840da580 1f20: ea541f3c ea541f30 81bab4c0 81bab38c ea541f54 ea541f40 8025b9d4 8028f744 1f40: ea541fb0 40000000 ea541f84 ea541f58 80221bdc 8025b98c 00000000 82a1a04c 1f60: ea541fb0 0013ec10 ecac8b10 80221b30 00000000 5239c1e3 ea541fac 00000000 1f80: 00000000 003563b0 00000036 8020029c 840da580 00000036 00000000 ea541fa8 1fa0: 80200060 805d0d64 00000000 00000000 00000003 40946400 20000000 00000000 1fc0: 00000000 00000000 003563b0 00000036 00356378 00000000 00000001 76f810dc 1fe0: 76f80e88 76f80e78 00018fb8 00130a70 60000010 00000003 00000000 00000000 Call trace: [<814e23b4>] (subdev_8255_io) from [<814e20f0>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:831e9480 r5:0000f000 r4:814e23b4 [<814e2098>] (subdev_8255_do_config) from [<814e24a8>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814e2098>] (subdev_8255_do_config) from [<814e24a8>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:89b74000 [<814e2420>] (subdev_8255_io_init) from [<814e2658>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814e2420>] (subdev_8255_io_init) from [<814e2658>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:89b74000 r5:00000000 r4:831e9480 [<814e25e4>] (dev_8255_attach) from [<814d0fe0>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d307a0 r9:00000000 r8:831e9480 r7:ea541d90 r6:00000000 r5:831e9480 r4:82bd8a3c [<814d0ed8>] (comedi_device_attach) from [<814cc7e4>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:840da580 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:831e9480 r4:20000000 [<814cc718>] (do_devconfig_ioctl) from [<814cdb0c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000000 r5:831e9480 r4:89c8ef80 [<814cd7b8>] (comedi_unlocked_ioctl) from [<805d0f9c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814cd7b8>] (comedi_unlocked_ioctl) from [<805d0f9c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814cd7b8>] (comedi_unlocked_ioctl) from [<805d0f9c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814cd7b8>] (comedi_unlocked_ioctl) from [<805d0f9c>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:840da580 r9:00000003 r8:89c8ef80 r7:20000000 r6:40946400 r5:89c8ef81 r4:00000000 [<805d0d58>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea541fa8 to 0xea541ff0) 1fa0: 00000000 00000000 00000003 40946400 20000000 00000000 1fc0: 00000000 00000000 003563b0 00000036 00356378 00000000 00000001 76f810dc 1fe0: 76f80e88 76f80e78 00018fb8 00130a70 r10:00000036 r9:840da580 r8:8020029c r7:00000036 r6:003563b0 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