diff mbox

[v2,5/9] mkfs.btrfs: fix symlink names writing

Message ID 1307175564-25355-6-git-send-email-slyfox@gentoo.org (mailing list archive)
State New, archived
Headers show

Commit Message

Sergei Trofimovich June 4, 2011, 8:19 a.m. UTC
Found by valgrind:
==8968== Use of uninitialised value of size 8
==8968==    at 0x41CE7D: crc32c_le (crc32c.c:98)
==8968==    by 0x40A1D0: csum_tree_block_size (disk-io.c:82)
==8968==    by 0x40A2D4: csum_tree_block (disk-io.c:105)
==8968==    by 0x40A7D6: write_tree_block (disk-io.c:241)
==8968==    by 0x40ACEE: __commit_transaction (disk-io.c:354)
==8968==    by 0x40AE9E: btrfs_commit_transaction (disk-io.c:385)
==8968==    by 0x42CF66: make_image (mkfs.c:1061)
==8968==    by 0x42DE63: main (mkfs.c:1410)
==8968==  Uninitialised value was created by a stack allocation
==8968==    at 0x42B5FB: add_inode_items (mkfs.c:493)

readlink(2) does not write '\0' for us, so make it manually.

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
---
 mkfs.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
diff mbox

Patch

diff --git a/mkfs.c b/mkfs.c
index 9d7b792..8ff2b1e 100644
--- a/mkfs.c
+++ b/mkfs.c
@@ -692,45 +692,47 @@  static int record_file_extent(struct btrfs_trans_handle *trans,
 				   root->root_key.objectid,
 				   objectid, 0);
 fail:
 	btrfs_release_path(root, &path);
 	return ret;
 }
 
 static int add_symbolic_link(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root,
 			     u64 objectid, const char *path_name)
 {
 	int ret;
 	u64 sectorsize = root->sectorsize;
 	char *buf = malloc(sectorsize);
 
 	ret = readlink(path_name, buf, sectorsize);
 	if (ret <= 0) {
 		fprintf(stderr, "readlink failed for %s\n", path_name);
 		goto fail;
 	}
-	if (ret > sectorsize) {
+	if (ret >= sectorsize) {
 		fprintf(stderr, "symlink too long for %s", path_name);
 		ret = -1;
 		goto fail;
 	}
+
+	buf[ret] = '\0'; /* readlink does not do it for us */
 	ret = btrfs_insert_inline_extent(trans, root, objectid, 0,
 					 buf, ret + 1);
 fail:
 	free(buf);
 	return ret;
 }
 
 static int add_file_items(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *root,
 			  struct btrfs_inode_item *btrfs_inode, u64 objectid,
 			  ino_t parent_inum, struct stat *st,
 			  const char *path_name, int out_fd)
 {
 	int ret;
 	ssize_t ret_read;
 	u64 bytes_read = 0;
 	char *buffer = NULL;
 	struct btrfs_key key;
 	int blocks;
 	u32 sectorsize = root->sectorsize;