xfs: ensure committed is initialized in xfs_trans_roll

__xfs_trans_roll() can return without setting the
*committed argument; this was a problem for xfs_bmap_finish():

        int       committed;/* xact committed or not */
...
        error = __xfs_trans_roll(tp, ip, &committed);
        if (error) {
...
                if (committed) {

and we tested an uninitialized "committed" variable on the
error path.  No caller is preserving "committed" state across
calls to __xfs_trans_roll(), so just initialize committed inside
the function to avoid future errors like this.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 748b16aff45a..20c53666cb4b 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -1028,6 +1028,8 @@ __xfs_trans_roll(
         struct xfs_trans_res    tres;
         int                     error;
 
+        *committed = 0;
+
         /*
          * Ensure that the inode is always logged.
          */
@@ -1082,6 +1084,6 @@ xfs_trans_roll(
         struct xfs_trans        **tpp,
         struct xfs_inode        *dp)
 {
-        int                     committed = 0;
+        int                     committed;
         return __xfs_trans_roll(tpp, dp, &committed);
 }