From 6487a9d3b5476ffd1bbbe97e58cf26dbeb7a5d4a Mon Sep 17 00:00:00 2001 From: Curt Wohlgemuth Date: Fri, 17 Jul 2009 10:54:08 -0400 Subject: ext4: More buffer head reference leaks After the patch I posted last week regarding buffer head ref leaks in no-journal mode, I looked at all the code that uses buffer heads and searched for more potential leaks. The patch below fixes the issues I found; these can occur even when a journal is present. The change to inode.c fixes a double release if ext4_journal_get_create_access() fails. The changes to namei.c are more complicated. add_dirent_to_buf() will release the input buffer head EXCEPT when it returns -ENOSPC. There are some callers of this routine that don't always do the brelse() in the event that -ENOSPC is returned. Unfortunately, to put this fix into ext4_add_entry() required capturing the return value of make_indexed_dir() and add_dirent_to_buf(). Signed-off-by: Curt Wohlgemuth Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 3 ++- fs/ext4/namei.c | 16 ++++++++++++---- 2 files changed, 14 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index f9c642b22ef..deb14a72879 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -762,8 +762,9 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode, BUFFER_TRACE(bh, "call get_create_access"); err = ext4_journal_get_create_access(handle, bh); if (err) { + /* Don't brelse(bh) here; it's done in + * ext4_journal_forget() below */ unlock_buffer(bh); - brelse(bh); goto failed; } diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 114abe5d2c1..fea14dbd3c2 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1518,8 +1518,12 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, return retval; if (blocks == 1 && !dx_fallback && - EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) - return make_indexed_dir(handle, dentry, inode, bh); + EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) { + retval = make_indexed_dir(handle, dentry, inode, bh); + if (retval == -ENOSPC) + brelse(bh); + return retval; + } brelse(bh); } bh = ext4_append(handle, dir, &block, &retval); @@ -1528,7 +1532,10 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, de = (struct ext4_dir_entry_2 *) bh->b_data; de->inode = 0; de->rec_len = ext4_rec_len_to_disk(blocksize, blocksize); - return add_dirent_to_buf(handle, dentry, inode, de, bh); + retval = add_dirent_to_buf(handle, dentry, inode, de, bh); + if (retval == -ENOSPC) + brelse(bh); + return retval; } /* @@ -1657,7 +1664,8 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry, if (!de) goto cleanup; err = add_dirent_to_buf(handle, dentry, inode, de, bh); - bh = NULL; + if (err != -ENOSPC) + bh = NULL; goto cleanup; journal_error: -- cgit v1.2.3