Always specify AT_UNNAMED when opening unnamed stream with libntfs-3g

[wimlib] / src / ntfs-3g_apply.c

diff --git a/src/ntfs-3g_apply.c b/src/ntfs-3g_apply.c
index ba90fae8f51e257c20c20718d85ccce6a1fe46a4..148abc769f058373ad5f350cfad773ae0c269bc7 100644 (file)
--- a/src/ntfs-3g_apply.c
+++ b/src/ntfs-3g_apply.c
@@ -30,6 +30,7 @@
 #  include "config.h"
 #endif
 
+#include <errno.h>
 #include <locale.h>
 #include <string.h>
 
@@ -123,10 +124,7 @@ sid_size(const wimlib_SID *sid)
 static void *
 sd_fixup(const void *_desc, size_t *size_p)
 {
-       u32 owner_offset, group_offset, dacl_offset;
-#if !defined(HAVE_NTFS_MNT_RDONLY)
-       u32 sacl_offset;
-#endif
+       u32 owner_offset, group_offset, dacl_offset, sacl_offset;
        bool owner_valid, group_valid;
        size_t size = *size_p;
        const wimlib_SECURITY_DESCRIPTOR_RELATIVE *desc = _desc;
@@ -142,23 +140,15 @@ sd_fixup(const void *_desc, size_t *size_p)
        else
                dacl_offset = 0;
 
-#if !defined(HAVE_NTFS_MNT_RDONLY)
        if (le16_to_cpu(desc->control) & wimlib_SE_SACL_PRESENT)
                sacl_offset = le32_to_cpu(desc->sacl_offset);
        else
                sacl_offset = 0;
-#endif
 
        /* Check if the security descriptor will be affected by one of the bugs.
-        * If not, do nothing and return.
-        *
-        * Note: HAVE_NTFS_MNT_RDONLY is defined if libntfs-3g is
-        * version 2013.1.13 or later.  */
-       if (!(
-       #if !defined(HAVE_NTFS_MNT_RDONLY)
-           (sacl_offset != 0 && sacl_offset == size - sizeof(wimlib_ACL)) ||
-       #endif
-           (dacl_offset != 0 && dacl_offset == size - sizeof(wimlib_ACL))))
+        * If not, do nothing and return.  */
+       if (!((sacl_offset != 0 && sacl_offset == size - sizeof(wimlib_ACL)) ||
+             (dacl_offset != 0 && dacl_offset == size - sizeof(wimlib_ACL))))
                return NULL;
 
        owner_offset = le32_to_cpu(desc->owner_offset);
@@ -426,15 +416,24 @@ ntfs_3g_set_metadata(ntfs_inode *ni, const struct wim_inode *inode,
                desc_size = sd->sizes[inode->i_security_id];
 
                ret = ntfs_3g_set_security_descriptor(ni, desc, desc_size);
-               if (ret) {
-                       if (wimlib_print_errors) {
-                               ERROR_WITH_ERRNO("Failed to set security descriptor "
-                                                "on \"%s\" in NTFS volume",
-                                                dentry_full_path(one_dentry));
+
+               if (unlikely(ret)) {
+                       int err = errno;
+                       ERROR_WITH_ERRNO("Failed to set security descriptor on "
+                                        "\"%s\" in NTFS volume",
+                                        dentry_full_path(one_dentry));
+                       if (err == EINVAL && wimlib_print_errors) {
                                fprintf(wimlib_error_file,
                                        "The security descriptor is: ");
                                print_byte_field(desc, desc_size, wimlib_error_file);
                                fprintf(wimlib_error_file, "\n");
+                               fprintf(wimlib_error_file,
+                                       "\nThis error occurred because libntfs-3g thinks "
+                                       "the security descriptor is invalid.  If you "
+                                       "are extracting a Windows 10 image, this may be "
+                                       "caused by a known bug in libntfs-3g.  See: "
+                                       "http://wimlib.net/forums/viewtopic.php?f=1&t=4 "
+                                       "for more information.\n\n");
                        }
                        return ret;
                }
@@ -715,6 +714,7 @@ ntfs_3g_begin_extract_blob_instance(struct blob_descriptor *blob,
                                    struct ntfs_3g_apply_ctx *ctx)
 {
        struct wim_dentry *one_dentry = inode_first_extraction_dentry(inode);
+       ntfschar *stream_name;
        size_t stream_name_nchars;
        ntfs_attr *attr;
 
@@ -737,22 +737,29 @@ ntfs_3g_begin_extract_blob_instance(struct blob_descriptor *blob,
        /* It's a data stream (may be unnamed or named).  */
        wimlib_assert(strm->stream_type == STREAM_TYPE_DATA);
 
-       stream_name_nchars = utf16le_len_chars(strm->stream_name);
+       if (unlikely(stream_is_named(strm))) {
+               stream_name = strm->stream_name;
+               stream_name_nchars = utf16le_len_chars(stream_name);
 
-       if (stream_name_nchars &&
-           (ntfs_attr_add(ni, AT_DATA, strm->stream_name,
-                          stream_name_nchars, NULL, 0)))
-       {
-               ERROR_WITH_ERRNO("Failed to create named data stream of \"%s\"",
-                                dentry_full_path(one_dentry));
-               return WIMLIB_ERR_NTFS_3G;
+               if (ntfs_attr_add(ni, AT_DATA, stream_name,
+                                 stream_name_nchars, NULL, 0))
+               {
+                       ERROR_WITH_ERRNO("Failed to create named data stream of \"%s\"",
+                                        dentry_full_path(one_dentry));
+                       return WIMLIB_ERR_NTFS_3G;
+               }
+       } else {
+               /* Don't pass an empty string other than AT_UNNAMED to
+                * ntfs_attr_open() --- it violates assumptions made by
+                * libntfs-3g.  */
+               stream_name = AT_UNNAMED;
+               stream_name_nchars = 0;
        }
 
        /* This should be ensured by extract_blob_list()  */
        wimlib_assert(ctx->num_open_attrs < MAX_OPEN_FILES);
 
-       attr = ntfs_attr_open(ni, AT_DATA, strm->stream_name,
-                             stream_name_nchars);
+       attr = ntfs_attr_open(ni, AT_DATA, stream_name, stream_name_nchars);
        if (!attr) {
                ERROR_WITH_ERRNO("Failed to open data stream of \"%s\"",
                                 dentry_full_path(one_dentry));