hfsplus: fix possible deadlock when handling corrupted extents

A corrupted extent for the extent file itself may try to get an impossible extent, causing a deadlock if I see it correctly. Check the inode number after the first_blocks checks and fail if it's the extent file, as according to the spec the extent file should have no extent for itself. Signed-off-by: Eric Sesterhenn <[email protected]> Cc: Roman Zippel <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
jadonk · Oct 20, 2008 · 248736c · 248736c
1 parent 6e71529
commit 248736c
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/fs/hfsplus/extents.c b/fs/hfsplus/extents.c
@@ -199,6 +199,9 @@ int hfsplus_get_block(struct inode *inode, sector_t iblock,
 		goto done;
 	}
 
+	if (inode->i_ino == HFSPLUS_EXT_CNID)
+		return -EIO;
+
 	mutex_lock(&HFSPLUS_I(inode).extents_lock);
 	res = hfsplus_ext_read_extent(inode, ablock);
 	if (!res) {