[PATCH AUTOSEL 5.6 33/38] ext4: increase wait time needed before reuse of deleted inode numbers

From: Sasha Levin
Date: Fri Apr 24 2020 - 08:31:11 EST


From: Theodore Ts'o <tytso@xxxxxxx>

[ Upstream commit a17a9d935dc4a50acefaf319d58030f1da7f115a ]

Current wait times have proven to be too short to protect against inode
reuses that lead to metadata inconsistencies.

Now that we will retry the inode allocation if we can't find any
recently deleted inodes, it's a lot safer to increase the recently
deleted time from 5 seconds to a minute.

Link: https://lore.kernel.org/r/20200414023925.273867-1-tytso@xxxxxxx
Google-Bug-Id: 36602237
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ext4/ialloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index f95ee99091e4c..eab18b7b56e77 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -663,7 +663,7 @@ static int find_group_other(struct super_block *sb, struct inode *parent,
* block has been written back to disk. (Yes, these values are
* somewhat arbitrary...)
*/
-#define RECENTCY_MIN 5
+#define RECENTCY_MIN 60
#define RECENTCY_DIRTY 300

static int recently_deleted(struct super_block *sb, ext4_group_t group, int ino)
--
2.20.1