[PATCH 3.13 026/172] jbd2: fix use after free in jbd2_journal_start_reserved()

From: Greg Kroah-Hartman
Date: Tue Mar 04 2014 - 16:34:20 EST


3.13-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 92e3b40537707001d17bbad800d150ab04e53bf4 upstream.

If start_this_handle() fails then it leads to a use after free of
"handle".

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/jbd2/transaction.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -514,11 +514,13 @@ int jbd2_journal_start_reserved(handle_t
* similarly constrained call sites
*/
ret = start_this_handle(journal, handle, GFP_NOFS);
- if (ret < 0)
+ if (ret < 0) {
jbd2_journal_free_reserved(handle);
+ return ret;
+ }
handle->h_type = type;
handle->h_line_no = line_no;
- return ret;
+ return 0;
}
EXPORT_SYMBOL(jbd2_journal_start_reserved);



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/