8<--- cut here --- Unable to handle kernel paging request at virtual address fee00303 when write [fee00303] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 20330 Comm: syz.4.5160 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 : [<8149bb18>] lr : [<8149bb04>] psr: 60000013 sp : eac79cb8 ip : eac79cb8 fp : eac79cd4 r10: 00000300 r9 : 00000004 r8 : eac79da4 r7 : 00000000 r6 : 0000009b r5 : 831d03c0 r4 : 00000303 r3 : 0000009b r2 : fee00303 r1 : 00000001 r0 : 831d03c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 874eff40 DAC: fffffffd Register r0 information: slab kmalloc-192 start 831d03c0 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 831d03c0 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 0xeac78000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xeac78000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Register r12 information: 2-page vmalloc region starting at 0xeac78000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Process syz.4.5160 (pid: 20330, stack limit = 0xeac78000) Stack: (0xeac79cb8 to 0xeac7a000) 9ca0: 8149bab8 00000300 9cc0: 831d03c0 00000000 eac79cf4 eac79cd8 8149b7f4 8149bac4 00000300 80545f10 9ce0: 83f94000 83f94000 eac79d14 eac79cf8 8149bbac 8149b7a8 831d03c0 00000000 9d00: 83f94000 00000000 eac79d54 eac79d18 8149bd5c 8149bb30 ffffffff 00000004 9d20: 82a22dc0 00000000 00000000 82bd95c0 831d03c0 00000000 eac79d90 831d03c0 9d40: 00000000 82d30df4 eac79d8c eac79d58 8148a700 8149bcf4 40946400 00000000 9d60: eac79d7c 20000440 831d03c0 b5403587 40946400 00000001 00000003 8475d5c0 9d80: eac79e4c eac79d90 81485f04 8148a604 35353238 00000000 00000000 00000000 9da0: 00000000 00000300 00000008 0000fca8 00006432 0000000e 00840006 7ffffffe 9dc0: 00000006 08000006 00000005 feffffff 0000000b 00000001 fffffffc 00000002 9de0: 00000003 00000005 0004007a 00000005 00007fff 0000000a 00000344 00000000 9e00: 00000001 00000005 00000e66 00000001 00006829 0800a6b5 00000000 00000005 9e20: 00000000 2a4ab65d 00000000 87405e80 831d03c0 20000440 40946400 00000001 9e40: eac79f14 eac79e50 8148722c 81485e44 00000000 2a4ab65d 00000000 00000000 9e60: 8254780c eac79ea4 0000005f 84278408 00000064 831d03f0 eac79ee4 eac79e88 9e80: 80803604 807f9934 00000064 00000001 00000000 eac79ea4 85195c10 8343fe58 9ea0: 00006400 0000000b eac79e98 00000000 00000000 2a4ab65d 00000000 87405e80 9ec0: 40946400 20000440 20000440 87405e80 00000003 8475d5c0 eac79ef4 eac79ee8 9ee0: 80803738 2a4ab65d eac79f14 00000000 87405e81 40946400 20000440 87405e80 9f00: 00000003 8475d5c0 eac79fa4 eac79f18 805ba698 81486ee4 ecac8b10 8475d5c0 9f20: eac79f3c eac79f30 81b52020 81b51eec eac79f54 eac79f40 8025a790 8028e468 9f40: eac79fb0 40000000 eac79f84 eac79f58 80220bdc 8025a74c 00000000 82a1eb0c 9f60: eac79fb0 0013e9c0 ecac8b10 80220b30 00000000 2a4ab65d eac79fac 00000000 9f80: 00000000 00346310 00000036 8020029c 8475d5c0 00000036 00000000 eac79fa8 9fa0: 80200060 805ba460 00000000 00000000 00000003 40946400 20000440 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f200dc 9fe0: 76f1fe88 76f1fe78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<8149bab8>] (subdev_8255_io) from [<8149b7f4>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:831d03c0 r5:00000300 r4:8149bab8 [<8149b79c>] (subdev_8255_do_config) from [<8149bbac>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8149b79c>] (subdev_8255_do_config) from [<8149bbac>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:83f94000 [<8149bb24>] (subdev_8255_io_init) from [<8149bd5c>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<8149bb24>] (subdev_8255_io_init) from [<8149bd5c>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:83f94000 r5:00000000 r4:831d03c0 [<8149bce8>] (dev_8255_attach) from [<8148a700>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d30df4 r9:00000000 r8:831d03c0 r7:eac79d90 r6:00000000 r5:831d03c0 r4:82bd95c0 [<8148a5f8>] (comedi_device_attach) from [<81485f04>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:8475d5c0 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:831d03c0 r4:20000440 [<81485e38>] (do_devconfig_ioctl) from [<8148722c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000440 r5:831d03c0 r4:87405e80 [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8475d5c0 r9:00000003 r8:87405e80 r7:20000440 r6:40946400 r5:87405e81 r4:00000000 [<805ba454>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xeac79fa8 to 0xeac79ff0) 9fa0: 00000000 00000000 00000003 40946400 20000440 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f200dc 9fe0: 76f1fe88 76f1fe78 00018ebc 00130820 r10:00000036 r9:8475d5c0 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