Fix #1771: Deleting (not write protected) symlinks to write protected images gives...

https://github.com/BestImageViewer/geeqie/issues/1771

Function access() was used, but this function follows symlinks.

Instead use lstat for delete/move/rename operations.

diff --git a/src/filedata/filedata.cc b/src/filedata/filedata.cc
index 5c6a848a02cdbbbafd6075a3026778615ba603ee..038b57d4ec47e25f2c2395b6fceea944efcb1927 100644 (file)
--- a/src/filedata/filedata.cc
+++ b/src/filedata/filedata.cc
@@ -23,6 +23,7 @@
 
 #include "filedata.h"
 
+#include <glib/gstdio.h>
 #include <sys/stat.h>
 #include <unistd.h>
 
@@ -1973,6 +1974,60 @@ gboolean FileData::file_data_sc_update_ci_unspecified_list(GList *fd_list, const
  * it should detect all possible problems with the planned operation
  */
 
+/**
+ * @brief Determine if file is readable, do not follow symlinks
+ * @param path 
+ * @returns 
+ * 
+ * 
+ */
+static gboolean file_is_readable_no_follow(const gchar *path)
+{
+       gboolean readable = FALSE;
+       GStatBuf statbuf;
+
+       if (g_lstat(path, &statbuf) != 0)
+               {
+               log_printf("g_lstat failed: %s\n", strerror(errno));
+
+               return readable;
+               }
+
+       if (S_IRUSR & statbuf.st_mode)
+               {
+               readable = TRUE;
+               }
+
+       return readable;
+}
+
+/**
+ * @brief Determine if file is writable, do not follow symlinks
+ * @param path 
+ * @returns 
+ * 
+ * 
+ */
+static gboolean file_is_writable_no_follow(const gchar *path)
+{
+       gboolean writable = FALSE;
+       GStatBuf statbuf;
+
+       if (g_lstat(path, &statbuf) != 0)
+               {
+               log_printf("g_lstat failed: %s\n", strerror(errno));
+
+               return writable;
+               }
+
+       if (S_IWUSR & statbuf.st_mode)
+               {
+               writable = TRUE;
+               }
+
+       return writable;
+}
+
 gint FileData::file_data_verify_ci(FileData *fd, GList *list)
 {
        gint ret = CHANGE_OK;
@@ -2007,7 +2062,7 @@ gint FileData::file_data_verify_ci(FileData *fd, GList *list)
 
        if (fd->change->type != FILEDATA_CHANGE_DELETE &&
            fd->change->type != FILEDATA_CHANGE_WRITE_METADATA &&
-           !access_file(fd->path, R_OK))
+                !file_is_readable_no_follow(fd->path))
                {
                ret |= CHANGE_NO_READ_PERM;
                DEBUG_1("Change checked: no read permission: %s", fd->path);
@@ -2021,7 +2076,7 @@ gint FileData::file_data_verify_ci(FileData *fd, GList *list)
        else if (fd->change->type != FILEDATA_CHANGE_COPY &&
                 fd->change->type != FILEDATA_CHANGE_UNSPECIFIED &&
                 fd->change->type != FILEDATA_CHANGE_WRITE_METADATA &&
-                !access_file(fd->path, W_OK))
+                !file_is_writable_no_follow(fd->path))
                {
                ret |= CHANGE_WARN_NO_WRITE_PERM;
                DEBUG_1("Change checked: no write permission: %s", fd->path);