[PATCH 5.10 099/289] f2fs: fix a redundant call to f2fs_balance_fs if an error occurs

From: Greg Kroah-Hartman
Date: Mon May 17 2021 - 11:32:47 EST

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

[ Upstream commit 28e18ee636ba28532dbe425540af06245a0bbecb ]

The uninitialized variable dn.node_changed does not get set when a
call to f2fs_get_node_page fails. This uninitialized value gets used
in the call to f2fs_balance_fs() that may or not may not balances
dirty node and dentry pages depending on the uninitialized state of
the variable. Fix this by only calling f2fs_balance_fs if err is
not set.

Thanks to Jaegeuk Kim for suggesting an appropriate fix.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: 2a3407607028 ("f2fs: call f2fs_balance_fs only when node was changed")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
fs/f2fs/inline.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index b9e37f0b3e09..1d7dafdaffe3 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -218,7 +218,8 @@ out:

f2fs_put_page(page, 1);

- f2fs_balance_fs(sbi, dn.node_changed);
+ if (!err)
+ f2fs_balance_fs(sbi, dn.node_changed);

return err;