8<--- cut here --- Unable to handle kernel paging request at virtual address fee02f03 when write [fee02f03] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 21645 Comm: syz.9.4236 Not tainted syzkaller #0 PREEMPT 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 : [<814ad81c>] lr : [<814ad808>] psr: 60000013 sp : dfb85cb8 ip : dfb85cb8 fp : dfb85cd4 r10: 00002f00 r9 : 00000004 r8 : dfb85da4 r7 : 00000000 r6 : 0000009b r5 : 848610c0 r4 : 00002f03 r3 : 0000009b r2 : fee02f03 r1 : 00000001 r0 : 848610c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8392b040 DAC: 00000000 Register r0 information: slab kmalloc-192 start 848610c0 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 848610c0 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 0xdfb84000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfb84000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Register r12 information: 2-page vmalloc region starting at 0xdfb84000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Process syz.9.4236 (pid: 21645, stack limit = 0xdfb84000) Stack: (0xdfb85cb8 to 0xdfb86000) 5ca0: 814ad7bc 00002f00 5cc0: 848610c0 00000000 dfb85cf4 dfb85cd8 814ad4f8 814ad7c8 00002f00 80547798 5ce0: 83329000 83329000 dfb85d14 dfb85cf8 814ad8b0 814ad4ac 848610c0 00000000 5d00: 83329000 00000000 dfb85d54 dfb85d18 814ada60 814ad834 ffffffff 00000004 5d20: 82a22dc0 00000000 00000000 82bdac60 848610c0 00000000 dfb85d90 848610c0 5d40: 00000000 82d32f9c dfb85d8c dfb85d58 8149c3e8 814ad9f8 40946400 00000000 5d60: dfb85d7c 20000300 848610c0 b5403587 40946400 00000001 00000003 8399e200 5d80: dfb85e4c dfb85d90 81497bec 8149c2ec 35353238 00000000 00000000 00000000 5da0: 00000000 00002f00 00000005 0000d09a ffffffff 00000003 fffffffe 20000004 5dc0: 00000003 00000ffe 7fffffff 00000005 00000002 00000004 00000008 0000fffc 5de0: 00000006 00000005 000007ff 00100830 00000008 00010000 00000009 00000c4f 5e00: 00000101 00000002 00008001 00000004 00000003 00000000 00000002 0000070f 5e20: 00000000 f4f0f6ed 00000000 8f791980 848610c0 20000300 40946400 00000001 5e40: dfb85f14 dfb85e50 81498f14 81497b2c 00000000 f4f0f6ed 00000000 00000000 5e60: 8254e844 dfb85ea4 0000005f 841ccd40 00000064 848610f0 dfb85ee4 dfb85e88 5e80: 8080b76c 80801e24 00000064 00000001 00000000 dfb85ea4 8572ca10 8343b198 5ea0: 00006400 0000000b dfb85e98 00000000 00000000 f4f0f6ed 00000000 8f791980 5ec0: 40946400 20000300 20000300 8f791980 00000003 8399e200 dfb85ef4 dfb85ee8 5ee0: 8080b8a0 f4f0f6ed dfb85f14 00000000 8f791981 40946400 20000300 8f791980 5f00: 00000003 8399e200 dfb85fa4 dfb85f18 805bdf78 81498bcc ecac8b10 8399e200 5f20: dfb85f3c dfb85f30 81b6ec00 81b6eacc dfb85f54 dfb85f40 8025b878 8028f548 5f40: dfb85fb0 40000000 dfb85f84 dfb85f58 80221bdc 8025b834 00000000 82a1eb0c 5f60: dfb85fb0 0013ebf0 ecac8b10 80221b30 00000000 f4f0f6ed dfb85fac 00000000 5f80: 00000000 00356310 00000036 8020029c 8399e200 00000036 00000000 dfb85fa8 5fa0: 80200060 805bdd40 00000000 00000000 00000003 40946400 20000300 00000000 5fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f360dc 5fe0: 76f35e88 76f35e78 00018fa0 00130a50 60000010 00000003 00000000 00000000 Call trace: [<814ad7bc>] (subdev_8255_io) from [<814ad4f8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:848610c0 r5:00002f00 r4:814ad7bc [<814ad4a0>] (subdev_8255_do_config) from [<814ad8b0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814ad4a0>] (subdev_8255_do_config) from [<814ad8b0>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:83329000 [<814ad828>] (subdev_8255_io_init) from [<814ada60>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814ad828>] (subdev_8255_io_init) from [<814ada60>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:83329000 r5:00000000 r4:848610c0 [<814ad9ec>] (dev_8255_attach) from [<8149c3e8>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d32f9c r9:00000000 r8:848610c0 r7:dfb85d90 r6:00000000 r5:848610c0 r4:82bdac60 [<8149c2e0>] (comedi_device_attach) from [<81497bec>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:8399e200 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:848610c0 r4:20000300 [<81497b20>] (do_devconfig_ioctl) from [<81498f14>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000300 r5:848610c0 r4:8f791980 [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8399e200 r9:00000003 r8:8f791980 r7:20000300 r6:40946400 r5:8f791981 r4:00000000 [<805bdd34>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb85fa8 to 0xdfb85ff0) 5fa0: 00000000 00000000 00000003 40946400 20000300 00000000 5fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f360dc 5fe0: 76f35e88 76f35e78 00018fa0 00130a50 r10:00000036 r9:8399e200 r8:8020029c r7:00000036 r6:00356310 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