nilfs2: fix buffer head leak in nilfs_btnode_submit_block
nilfs_btnode_submit_block() refers to buffer head just before
returning from the function, but it releases the buffer head earlier
than that if nilfs_dat_translate() gets an error.
This has potential for oops in the erroneous case. This fixes the
issue.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 447ce47..0a6834b 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -100,6 +100,7 @@
{
struct buffer_head *bh;
struct inode *inode = NILFS_BTNC_I(btnc);
+ struct page *page;
int err;
bh = nilfs_grab_buffer(inode, btnc, blocknr, 1 << BH_NILFS_Node);
@@ -107,6 +108,7 @@
return -ENOMEM;
err = -EEXIST; /* internal code */
+ page = bh->b_page;
if (buffer_uptodate(bh) || buffer_dirty(bh))
goto found;
@@ -143,8 +145,8 @@
*pbh = bh;
out_locked:
- unlock_page(bh->b_page);
- page_cache_release(bh->b_page);
+ unlock_page(page);
+ page_cache_release(page);
return err;
}