cpio: (allegedly) fix bug 0001095:

"cpio hardlink support and possible memory leak fix"

archival/libunarchive/get_header_cpio.c

@@ -8,7 +8,7 @@
 #include "unarchive.h"
 
 typedef struct hardlinks_s {
-	file_header_t *entry;
+	char *name;
 	int inode;
 	struct hardlinks_s *next;
 } hardlinks_t;
@@ -17,46 +17,66 @@ char get_header_cpio(archive_handle_t *archive_handle)
 {
 	static hardlinks_t *saved_hardlinks = NULL;
 	static unsigned short pending_hardlinks = 0;
+	static int inode;
 	file_header_t *file_header = archive_handle->file_header;
 	char cpio_header[110];
 	int namesize;
 	char dummy[16];
-	int major, minor, nlink, inode;
+	int major, minor, nlink;
 
 	if (pending_hardlinks) { /* Deal with any pending hardlinks */
-		hardlinks_t *tmp;
+		hardlinks_t *tmp, *oldtmp;
-		hardlinks_t *oldtmp;
 
 		tmp = saved_hardlinks;
 		oldtmp = NULL;
 
+		file_header->link_name = file_header->name;
+		file_header->size = 0;
+
 		while (tmp) {
-			bb_error_msg_and_die("need to fix this");
+			if (tmp->inode != inode) {
-			if (tmp->entry->link_name) { /* Found a hardlink ready to be extracted */
+				tmp = tmp->next;
-				file_header = tmp->entry;
-				if (oldtmp) {
-					oldtmp->next = tmp->next; /* Remove item from linked list */
-				} else {
-					saved_hardlinks = tmp->next;
-				}
-				free(tmp);
 				continue;
 			}
+
+			file_header->name = tmp->name;
+
+			if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
+				archive_handle->action_data(archive_handle);
+				archive_handle->action_header(archive_handle->file_header);
+			}
+
+			pending_hardlinks--;
+
 			oldtmp = tmp;
 			tmp = tmp->next;
+			free(oldtmp->name);
+			free(oldtmp);
+			if (oldtmp == saved_hardlinks)
+				saved_hardlinks = tmp;
 		}
-		pending_hardlinks = 0; /* No more pending hardlinks, read next file entry */
+
+		file_header->name = file_header->link_name;
+
+		if (pending_hardlinks > 1) {
+			bb_error_msg("error resolving hardlink: archive made by GNU cpio 2.0-2.2?");
+		}
+
+		/* No more pending hardlinks, read next file entry */
+		pending_hardlinks = 0;
 	}
 
 	/* There can be padding before archive header */
 	data_align(archive_handle, 4);
 
 	if (archive_xread_all_eof(archive_handle, (unsigned char*)cpio_header, 110) == 0) {
-		return(EXIT_FAILURE);
+		return EXIT_FAILURE;
 	}
 	archive_handle->offset += 110;
 
-	if ((strncmp(&cpio_header[0], "07070", 5) != 0) || ((cpio_header[5] != '1') && (cpio_header[5] != '2'))) {
+	if (strncmp(&cpio_header[0], "07070", 5) != 0
+	 || (cpio_header[5] != '1' && cpio_header[5] != '2')
+	) {
 		bb_error_msg_and_die("unsupported cpio format, use newc or crc");
 	}
 
@@ -70,7 +90,8 @@ char get_header_cpio(archive_handle_t *archive_handle)
 		file_header->size = tmpsize;
 	}
 
-	file_header->name = (char *) xzalloc(namesize + 1);
+	free(file_header->name);
+	file_header->name = xzalloc(namesize + 1);
 	/* Read in filename */
 	xread(archive_handle->src_fd, file_header->name, namesize);
 	archive_handle->offset += namesize;
@@ -79,26 +100,29 @@ char get_header_cpio(archive_handle_t *archive_handle)
 	data_align(archive_handle, 4);
 
 	if (strcmp(file_header->name, "TRAILER!!!") == 0) {
-		printf("%d blocks\n", (int) (archive_handle->offset % 512 ? (archive_handle->offset / 512) + 1 : archive_handle->offset / 512)); /* Always round up */
+		/* Always round up */
+		printf("%d blocks\n", (int) (archive_handle->offset % 512 ?
+		                             archive_handle->offset / 512 + 1 :
+                                             archive_handle->offset / 512
+		                            ));
 		if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
 			hardlinks_t *tmp = saved_hardlinks;
 			hardlinks_t *oldtmp = NULL;
 			while (tmp) {
-				bb_error_msg("%s not created: cannot resolve hardlink", tmp->entry->name);
+				bb_error_msg("%s not created: cannot resolve hardlink", tmp->name);
 				oldtmp = tmp;
 				tmp = tmp->next;
-				free (oldtmp->entry->name);
+				free(oldtmp->name);
-				free (oldtmp->entry);
+				free(oldtmp);
-				free (oldtmp);
 			}
 			saved_hardlinks = NULL;
 			pending_hardlinks = 0;
 		}
-		return(EXIT_FAILURE);
+		return EXIT_FAILURE;
 	}
 
 	if (S_ISLNK(file_header->mode)) {
-		file_header->link_name = (char *) xzalloc(file_header->size + 1);
+		file_header->link_name = xzalloc(file_header->size + 1);
 		xread(archive_handle->src_fd, file_header->link_name, file_header->size);
 		archive_handle->offset += file_header->size;
 		file_header->size = 0; /* Stop possible seeks in future */
@@ -110,23 +134,14 @@ char get_header_cpio(archive_handle_t *archive_handle)
 			hardlinks_t *new = xmalloc(sizeof(hardlinks_t));
 			new->next = saved_hardlinks;
 			new->inode = inode;
-			new->entry = file_header;
+			/* name current allocated, freed later */
+			new->name = file_header->name;
+			file_header->name = NULL;
 			saved_hardlinks = new;
-			return(EXIT_SUCCESS); // Skip this one
+			return EXIT_SUCCESS; /* Skip this one */
-		} else { /* Found the file with data in */
-			hardlinks_t *tmp = saved_hardlinks;
-			pending_hardlinks = 1;
-			while (tmp) {
-				if (tmp->inode == inode) {
-					tmp->entry->link_name = xstrdup(file_header->name);
-					nlink--;
-				}
-				tmp = tmp->next;
-			}
-			if (nlink > 1) {
-				bb_error_msg("error resolving hardlink: did you create the archive with GNU cpio 2.0-2.2?");
-			}
 		}
+		/* Found the file with data in */
+		pending_hardlinks = nlink;
 	}
 	file_header->device = makedev(major, minor);
 

archival/libunarchive/init_handle.c

@@ -12,7 +12,7 @@ archive_handle_t *init_handle(void)
 
 	/* Initialize default values */
 	archive_handle = xzalloc(sizeof(archive_handle_t));
-	archive_handle->file_header = xmalloc(sizeof(file_header_t));
+	archive_handle->file_header = xzalloc(sizeof(file_header_t));
 	archive_handle->action_header = header_skip;
 	archive_handle->action_data = data_skip;
 	archive_handle->filter = filter_accept_all;