Correct the cpio writers to not accept data for non-regular files.

In particular, the previous code led to archives that had
non-empty bodies following directory entries.  Not a fatal
problem, as bsdtar and GNU cpio are both happy to just skip
this bogus data, but it still shouldn't be there.

MFC after: 3 days

3 files changed, 41 insertions, 3 deletions

diff --git a/lib/libarchive/archive_write_set_format_cpio.c b/lib/libarchive/archive_write_set_format_cpio.c
index 80dbf38..ba23f32 100644
--- a/lib/libarchive/archive_write_set_format_cpio.c
+++ b/lib/libarchive/archive_write_set_format_cpio.c
@@ -142,12 +142,17 @@ archive_write_cpio_header(struct archive_write *a, struct archive_entry *entry)
 	format_octal(archive_entry_mtime(entry), &h.c_mtime, sizeof(h.c_mtime));
 	format_octal(pathlength, &h.c_namesize, sizeof(h.c_namesize));
 
+	/* Non-regular files don't store bodies. */
+	if (archive_entry_filetype(entry) != AE_IFREG)
+		archive_entry_set_size(entry, 0);
+
 	/* Symlinks get the link written as the body of the entry. */
 	p = archive_entry_symlink(entry);
 	if (p != NULL  &&  *p != '\0')
 		format_octal(strlen(p), &h.c_filesize, sizeof(h.c_filesize));
 	else
-		format_octal(archive_entry_size(entry), &h.c_filesize, sizeof(h.c_filesize));
+		format_octal(archive_entry_size(entry),
+		    &h.c_filesize, sizeof(h.c_filesize));
 
 	ret = (a->compressor.write)(a, &h, sizeof(h));
 	if (ret != ARCHIVE_OK)
diff --git a/lib/libarchive/archive_write_set_format_cpio_newc.c b/lib/libarchive/archive_write_set_format_cpio_newc.c
index b585597..37dd35a 100644
--- a/lib/libarchive/archive_write_set_format_cpio_newc.c
+++ b/lib/libarchive/archive_write_set_format_cpio_newc.c
@@ -148,12 +148,17 @@ archive_write_newc_header(struct archive_write *a, struct archive_entry *entry)
 	format_hex(pathlength, &h.c_namesize, sizeof(h.c_namesize));
 	format_hex(0, &h.c_checksum, sizeof(h.c_checksum));
 
+	/* Non-regular files don't store bodies. */
+	if (archive_entry_filetype(entry) != AE_IFREG)
+		archive_entry_set_size(entry, 0);
+
 	/* Symlinks get the link written as the body of the entry. */
 	p = archive_entry_symlink(entry);
 	if (p != NULL  &&  *p != '\0')
 		format_hex(strlen(p), &h.c_filesize, sizeof(h.c_filesize));
 	else
-		format_hex(archive_entry_size(entry), &h.c_filesize, sizeof(h.c_filesize));
+		format_hex(archive_entry_size(entry),
+		    &h.c_filesize, sizeof(h.c_filesize));
 
 	ret = (a->compressor.write)(a, &h, sizeof(h));
 	if (ret != ARCHIVE_OK)
diff --git a/lib/libarchive/test/test_write_format_cpio.c b/lib/libarchive/test/test_write_format_cpio.c
index 2ea40a3..886942e 100644
--- a/lib/libarchive/test/test_write_format_cpio.c
+++ b/lib/libarchive/test/test_write_format_cpio.c
@@ -66,6 +66,21 @@ test_format(int	(*set_format)(struct archive *))
 	archive_entry_free(ae);
 	assertA(8 == archive_write_data(a, "12345678", 9));
 
+	/*
+	 * Write a directory to it.
+	 */
+	assert((ae = archive_entry_new()) != NULL);
+	archive_entry_set_mtime(ae, 11, 110);
+	archive_entry_copy_pathname(ae, "dir");
+	archive_entry_set_mode(ae, S_IFDIR | 0755);
+	archive_entry_set_size(ae, 512);
+
+	assertA(0 == archive_write_header(a, ae));
+	assertEqualInt(0, archive_entry_size(ae));
+	archive_entry_free(ae);
+	assertEqualIntA(a, 0, archive_write_data(a, "12345678", 9));
+
+
 	/* Close out the archive. */
 	assertA(0 == archive_write_close(a));
 #if ARCHIVE_API_VERSION > 1
@@ -95,8 +110,21 @@ test_format(int	(*set_format)(struct archive *))
 	assertA(8 == archive_read_data(a, filedata, 10));
 	assert(0 == memcmp(filedata, "12345678", 8));
 
+	/*
+	 * Read the dir entry back.
+	 */
+	assertA(0 == archive_read_next_header(a, &ae));
+	assert(11 == archive_entry_mtime(ae));
+	assert(0 == archive_entry_mtime_nsec(ae));
+	assert(0 == archive_entry_atime(ae));
+	assert(0 == archive_entry_ctime(ae));
+	assertEqualString("dir", archive_entry_pathname(ae));
+	assert((S_IFDIR | 0755) == archive_entry_mode(ae));
+	assertEqualInt(0, archive_entry_size(ae));
+	assertEqualIntA(a, 0, archive_read_data(a, filedata, 10));
+
 	/* Verify the end of the archive. */
-	assert(1 == archive_read_next_header(a, &ae));
+	assertEqualIntA(a, 1, archive_read_next_header(a, &ae));
 	assert(0 == archive_read_close(a));
 #if ARCHIVE_API_VERSION > 1
 	assert(0 == archive_read_finish(a));