ext4: Fix credit estimate for final inode freeing

Estimate for the number of credits needed for final freeing of inode in
ext4_evict_inode() was to small. We may modify 4 blocks (inode & sb for
orphan deletion, bitmap & group descriptor for inode freeing) and not
just 3.

[ Fixed minor whitespace nit. -- TYT ]

Fixes: e50e5129f384 ("ext4: xattr-in-inode support")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 516faa280ceda8d8035363f63153bbdac4901002..22ccab6c485eabd225ad4187e2aa6aa2e2681620 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -196,7 +196,12 @@ void ext4_evict_inode(struct inode *inode)
 {
        handle_t *handle;
        int err;
-       int extra_credits = 3;
+       /*
+        * Credits for final inode cleanup and freeing:
+        * sb + inode (ext4_orphan_del()), block bitmap, group descriptor
+        * (xattr block freeing), bitmap, group descriptor (inode freeing)
+        */
+       int extra_credits = 6;
        struct ext4_xattr_inode_array *ea_inode_array = NULL;
 
        trace_ext4_evict_inode(inode);
@@ -252,8 +257,12 @@ void ext4_evict_inode(struct inode *inode)
        if (!IS_NOQUOTA(inode))
                extra_credits += EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb);
 
+       /*
+        * Block bitmap, group descriptor, and inode are accounted in both
+        * ext4_blocks_for_truncate() and extra_credits. So subtract 3.
+        */
        handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
-                                ext4_blocks_for_truncate(inode)+extra_credits);
+                        ext4_blocks_for_truncate(inode) + extra_credits - 3);
        if (IS_ERR(handle)) {
                ext4_std_error(inode->i_sb, PTR_ERR(handle));
                /*