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: 1 UID: 0 PID: 21894 Comm: syz.2.2502 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 : [<813db868>] lr : [<813db854>] psr: 60000013 sp : dfa89cb8 ip : dfa89cb8 fp : dfa89cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 8425b180 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8425b180 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85864200 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8425b180 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 8425b180 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 0xdfa88000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa88000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.2.2502 (pid: 21894, stack limit = 0xdfa88000) Stack: (0xdfa89cb8 to 0xdfa8a000) 9ca0: 813db808 8425b180 9cc0: 00004f27 00004f27 dfa89cf4 dfa89cd8 813db540 813db814 00004f27 8050a88c 9ce0: 868e1000 868e1000 dfa89d14 dfa89cf8 813db900 813db4f4 868e1000 8425b180 9d00: dfa89da4 00004f27 dfa89d54 dfa89d18 813dbaf4 813db880 82af1fe0 84ec8600 9d20: 828215f0 00000000 00000000 829d23cc 8425b180 8425b1c4 dfa89d90 8425b180 9d40: 00000000 82b25910 dfa89d8c dfa89d58 813ca9ec 813dba44 200000c0 00000000 9d60: dfa89d7c 200000c0 8425b180 b5403587 200000c0 841fec00 40946400 00000003 9d80: dfa89e4c dfa89d90 813c6538 813ca8f0 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000002 000003fd 00000001 00000cc7 00000fff 9dc0: 5c952399 00010005 000003ff 00000802 00001600 00000001 00000001 00000009 9de0: 0000e1cb 00000009 00000004 08000007 00000395 80000089 fffffffd 00000000 9e00: 00000004 ffffeadb 00000003 0000003c 00000008 00000002 08000000 dffffffa 9e20: 00000000 1ba25e3a 00000000 86aec6c0 8425b180 200000c0 200000c0 841fec00 9e40: dfa89f14 dfa89e50 813c7504 813c6444 00000000 00000000 00000000 1ba25e3a 9e60: 00000000 00000000 824625b4 0000005f 83ed17f8 8425b1b0 8389348c 841fec00 9e80: dfa89ee4 dfa89e90 807a7cbc 8079e0b4 00000064 00000001 00000000 dfa89eac 9ea0: 872df0d0 83423e58 00006400 0000000b dfa89ea0 00000000 00000000 1ba25e3a 9ec0: 86aec6c0 40946400 200000c0 200000c0 86aec6c0 00000007 dfa89ef4 dfa89ee8 9ee0: 807a7ddc 1ba25e3a dfa89f14 40946400 00000000 86aec6c1 200000c0 86aec6c0 9f00: 00000007 841fec00 dfa89fa4 dfa89f18 80578ee0 813c6f34 ecac8b10 841fec00 9f20: dfa89f3c dfa89f30 81a60d80 81a60c50 dfa89f54 dfa89f40 8025c484 8028d914 9f40: dfa89fb0 40000000 dfa89f84 dfa89f58 802229ec 8025c440 00000000 8281cfb4 9f60: dfa89fb0 0014ced0 ecac8b10 80222940 00000000 1ba25e3a dfa89fac 00000000 9f80: 00000000 00316308 00000036 8020029c 841fec00 00000036 00000000 dfa89fa8 9fa0: 80200060 80578dbc 00000000 00000000 00000007 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f2a0bc 9fe0: 76f29ec0 76f29eb0 0001928c 00132970 60000010 00000007 00000000 00000000 Call trace: [<813db808>] (subdev_8255_io) from [<813db540>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8425b180 r4:813db808 [<813db4e8>] (subdev_8255_do_config) from [<813db900>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db4e8>] (subdev_8255_do_config) from [<813db900>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:868e1000 [<813db874>] (subdev_8255_io_init) from [<813dbaf4>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db874>] (subdev_8255_io_init) from [<813dbaf4>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa89da4 r5:8425b180 r4:868e1000 [<813dba38>] (dev_8255_attach) from [<813ca9ec>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:8425b180 r7:dfa89d90 r6:8425b1c4 r5:8425b180 r4:829d23cc [<813ca8e4>] (comedi_device_attach) from [<813c6538>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:841fec00 r7:200000c0 r6:b5403587 r5:8425b180 r4:200000c0 [<813c6438>] (do_devconfig_ioctl) from [<813c7504>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:841fec00 r7:200000c0 r6:200000c0 r5:8425b180 r4:86aec6c0 [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:841fec00 r9:00000007 r8:86aec6c0 r7:200000c0 r6:86aec6c1 r5:00000000 r4:40946400 [<80578db0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa89fa8 to 0xdfa89ff0) 9fa0: 00000000 00000000 00000007 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f2a0bc 9fe0: 76f29ec0 76f29eb0 0001928c 00132970 r10:00000036 r9:841fec00 r8:8020029c r7:00000036 r6:00316308 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