reiserfs: workaround for dead loop in finish_unfinished (fb46f341) · Commits · 戴 / test

There is possible dead loop in finish_unfinished function. In most situation, the call chain iput -> ... -> reiserfs_delete_inode -> remove_save_link will success. But for some reason such as data corruption, reiserfs_delete_inode fails on reiserfs_do_truncate -> search_for_position_by_key. Then remove_save_link won't be called. We always get the same "save_link_key" in the while loop in finish_unfinished function. The following patch adds a check for the possible dead loop and just remove save link when deap loop. [akpm@linux-foundation.org: cleanups] Signed-off-by:

Lepton Wu <ytht.net@gmail.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Jeff Mahoney <jeffm@suse.com> Cc: "Vladimir V. Saveliev" <vs@namesys.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

fs/reiserfs/super.c

+15 −3

Original line number	Diff line number	Diff line
		@@ -145,7 +145,7 @@ static int finish_unfinished(struct super_block *s)
		{
		INITIALIZE_PATH(path);
		struct cpu_key max_cpu_key, obj_key;
		struct reiserfs_key save_link_key;
		struct reiserfs_key save_link_key, last_inode_key;
		int retval = 0;
		struct item_head *ih;
		struct buffer_head *bh;
		@@ -166,6 +166,8 @@ static int finish_unfinished(struct super_block *s)
		set_cpu_key_k_offset(&max_cpu_key, ~0U);
		max_cpu_key.key_length = 3;

		memset(&last_inode_key, 0, sizeof(last_inode_key));

		#ifdef CONFIG_QUOTA
		/* Needed for iput() to work correctly and not trash data */
		if (s->s_flags & MS_ACTIVE) {
		@@ -278,8 +280,18 @@ static int finish_unfinished(struct super_block *s)
		REISERFS_I(inode)->i_flags \|= i_link_saved_unlink_mask;
		/* not completed unlink (rmdir) found */
		reiserfs_info(s, "Removing %k..", INODE_PKEY(inode));
		if (memcmp(&last_inode_key, INODE_PKEY(inode),
		sizeof(last_inode_key))){
		last_inode_key = *INODE_PKEY(inode);
		/* removal gets completed in iput */
		retval = 0;
		} else {
		reiserfs_warning(s, "Dead loop in "
		"finish_unfinished detected, "
		"just remove save link\n");
		retval = remove_save_link_only(s,
		&save_link_key, 0);
		}
		}

		iput(inode);

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