Fix inname test case

* src/safe.h (unsafe): New flag to allow turning off safe file
operations.
* src/safe.c (safe_xstat, safe_open, safe_rename, safe_mkdir,
safe_rmdir, safe_unlink, safe_symlink, safe_chmod, safe_lchown,
safe_lutimens, safe_readlink, safe_access): When safe file operations
are turned off, skip safe path traversal.  Any symlink checks of the
last path component are still done though.
* src/patch.c (main): When the file to patch is specified on the command
line, turn off safe file operations.
* tests/inname: Fix typo in test.

src/patch.c

@@ -176,6 +176,12 @@ main (int argc, char **argv)
     /* Make sure we clean up in case of disaster.  */
     set_signals (false);
 
+    /* When the file to patch is specified on the command line, allow that file
+       to lie outside the current working tree.  Still doesn't allow to follow
+       symlinks.  */
+    if (inname)
+      unsafe = true;
+
     if (inname && outfile)
       {
 	/* When an input and an output filename is given and the patch is

src/safe.c

@@ -48,6 +48,10 @@
 
 static const unsigned int MAX_PATH_COMPONENTS = 1024;
 
+/* Flag to turn the safe_* functions into their unsafe variants; files may then
+   lie outside the current working directory. */
+bool unsafe;
+
 /* Path lookup results are cached in a hash table + LRU list. When the
    cache is full, the oldest entries are removed.  */
 
@@ -543,6 +547,9 @@ static int safe_xstat (const char *pathname, struct stat *buf, int flags)
 {
   int dirfd;
 
+  if (unsafe)
+    return fstatat (AT_FDCWD, pathname, buf, flags);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -566,6 +573,9 @@ int safe_open (const char *pathname, int flags, mode_t mode)
 {
   int dirfd;
 
+  if (unsafe)
+    return open (pathname, flags, mode);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -578,6 +588,9 @@ int safe_rename (const char *oldpath, const char *newpath)
   int olddirfd, newdirfd;
   int ret;
 
+  if (unsafe)
+    return rename (oldpath, newpath);
+
   olddirfd = traverse_path (&oldpath);
   if (olddirfd < 0 && olddirfd != AT_FDCWD)
     return olddirfd;
@@ -600,6 +613,9 @@ int safe_mkdir (const char *pathname, mode_t mode)
 {
   int dirfd;
 
+  if (unsafe)
+    return mkdir (pathname, mode);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -612,6 +628,9 @@ int safe_rmdir (const char *pathname)
   int dirfd;
   int ret;
 
+  if (unsafe)
+    return rmdir (pathname);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -627,6 +646,9 @@ int safe_unlink (const char *pathname)
 {
   int dirfd;
 
+  if (unsafe)
+    return unlink (pathname);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -638,6 +660,9 @@ int safe_symlink (const char *target, const char *linkpath)
 {
   int dirfd;
 
+  if (unsafe)
+    return symlink (target, linkpath);
+
   dirfd = traverse_path (&linkpath);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -649,6 +674,9 @@ int safe_chmod (const char *pathname, mode_t mode)
 {
   int dirfd;
 
+  if (unsafe)
+    return chmod (pathname, mode);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -660,6 +688,9 @@ int safe_lchown (const char *pathname, uid_t owner, gid_t group)
 {
   int dirfd;
 
+  if (unsafe)
+    return lchown (pathname, owner, group);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -671,6 +702,9 @@ int safe_lutimens (const char *pathname, struct timespec const times[2])
 {
   int dirfd;
 
+  if (unsafe)
+    return utimensat (AT_FDCWD, pathname, times, AT_SYMLINK_NOFOLLOW);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -682,6 +716,9 @@ ssize_t safe_readlink (const char *pathname, char *buf, size_t bufsiz)
 {
   int dirfd;
 
+  if (unsafe)
+    return readlink (pathname, buf, bufsiz);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;
@@ -693,6 +730,9 @@ int safe_access (const char *pathname, int mode)
 {
   int dirfd;
 
+  if (unsafe)
+    return access (pathname, mode);
+
   dirfd = traverse_path (&pathname);
   if (dirfd < 0 && dirfd != AT_FDCWD)
     return dirfd;

src/safe.h

@@ -18,6 +18,10 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+#include <stdbool.h>
+
+extern bool unsafe;
+
 int safe_stat (const char *pathname, struct stat *buf);
 int safe_lstat (const char *pathname, struct stat *buf);
 int safe_open (const char *pathname, int flags, mode_t mode);

tests/inname

@@ -51,5 +51,5 @@ cat > g.diff <<EOF
 EOF
 
 check 'patch ../file1 < g.diff' <<EOF
-patching file ../file
+patching file ../file1
 EOF