Rev 1293 | Go to most recent revision | Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
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| 1288 | jermar | 1 | /* |
| 2 | * Copyright (C) 2006 Jakub Jermar |
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| 3 | * All rights reserved. |
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| 4 | * |
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| 5 | * Redistribution and use in source and binary forms, with or without |
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| 6 | * modification, are permitted provided that the following conditions |
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| 7 | * are met: |
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| 8 | * |
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| 9 | * - Redistributions of source code must retain the above copyright |
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| 10 | * notice, this list of conditions and the following disclaimer. |
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| 11 | * - Redistributions in binary form must reproduce the above copyright |
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| 12 | * notice, this list of conditions and the following disclaimer in the |
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| 13 | * documentation and/or other materials provided with the distribution. |
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| 14 | * - The name of the author may not be used to endorse or promote products |
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| 15 | * derived from this software without specific prior written permission. |
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| 16 | * |
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| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
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| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
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| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
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| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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| 27 | */ |
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| 28 | |||
| 29 | /** |
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| 30 | * @file copy.c |
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| 31 | * @brief Copying between kernel and userspace. |
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| 32 | * |
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| 33 | * This file contains sanitized functions for copying data |
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| 34 | * between kernel and userspace. |
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| 35 | */ |
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| 36 | |||
| 37 | #include <syscall/copy.h> |
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| 38 | #include <proc/thread.h> |
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| 39 | #include <mm/as.h> |
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| 40 | #include <macros.h> |
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| 41 | #include <arch.h> |
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| 42 | #include <errno.h> |
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| 43 | #include <typedefs.h> |
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| 44 | |||
| 45 | /** Copy data from userspace to kernel. |
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| 46 | * |
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| 47 | * Provisions are made to return value even after page fault. |
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| 48 | * |
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| 49 | * This function can be called only from syscall. |
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| 50 | * |
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| 51 | * @param dst Destination kernel address. |
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| 52 | * @param uspace_src Source userspace address. |
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| 53 | * @param size Size of the data to be copied. |
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| 54 | * |
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| 55 | * @return 0 on success or error code from @ref errno.h. |
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| 56 | */ |
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| 57 | int copy_from_uspace(void *dst, void *uspace_src, size_t size) |
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| 58 | { |
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| 59 | ipl_t ipl; |
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| 60 | int rc; |
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| 61 | |||
| 62 | ASSERT(THREAD); |
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| 63 | ASSERT(!THREAD->in_copy_from_uspace); |
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| 64 | |||
| 65 | if (!KERNEL_ADDRESS_SPACE_SHADOWED) { |
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| 66 | if (overlaps((__address) uspace_src, size, |
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| 67 | KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START)) { |
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| 68 | /* |
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| 69 | * The userspace source block conflicts with kernel address space. |
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| 70 | */ |
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| 71 | return EPERM; |
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| 72 | } |
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| 73 | } |
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| 74 | |||
| 75 | ipl = interrupts_disable(); |
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| 76 | THREAD->in_copy_from_uspace = true; |
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| 77 | |||
| 78 | rc = memcpy_from_uspace(dst, uspace_src, size); |
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| 79 | |||
| 80 | THREAD->in_copy_from_uspace = false; |
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| 81 | |||
| 82 | interrupts_restore(ipl); |
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| 83 | return !rc ? EPERM : 0; |
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| 84 | } |
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| 85 | |||
| 86 | /** Copy data from kernel to userspace. |
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| 87 | * |
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| 88 | * Provisions are made to return value even after page fault. |
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| 89 | * |
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| 90 | * This function can be called only from syscall. |
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| 91 | * |
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| 92 | * @param uspace_dst Destination userspace address. |
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| 93 | * @param uspace_src Source kernel address. |
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| 94 | * @param size Size of the data to be copied. |
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| 95 | * |
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| 96 | * @return 0 on success or error code from @ref errno.h. |
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| 97 | */ |
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| 98 | int copy_to_uspace(void *uspace_dst, void *src, size_t size) |
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| 99 | { |
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| 100 | ipl_t ipl; |
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| 101 | int rc; |
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| 102 | |||
| 103 | ASSERT(THREAD); |
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| 104 | ASSERT(!THREAD->in_copy_from_uspace); |
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| 105 | |||
| 106 | if (!KERNEL_ADDRESS_SPACE_SHADOWED) { |
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| 107 | if (overlaps((__address) uspace_dst, size, |
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| 108 | KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START)) { |
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| 109 | /* |
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| 110 | * The userspace destination block conflicts with kernel address space. |
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| 111 | */ |
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| 112 | return EPERM; |
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| 113 | } |
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| 114 | } |
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| 115 | |||
| 116 | ipl = interrupts_disable(); |
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| 117 | THREAD->in_copy_from_uspace = true; |
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| 118 | |||
| 119 | rc = memcpy_to_uspace(uspace_dst, src, size); |
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| 120 | |||
| 121 | THREAD->in_copy_from_uspace = false; |
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| 122 | |||
| 123 | interrupts_restore(ipl); |
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| 124 | return !rc ? EPERM : 0; |
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| 125 | } |