From 06f47bf994512f6b68430b13635cdc75478ad10d Mon Sep 17 00:00:00 2001
From: "Luis Henriques (SUSE)" <luis.henriques@linux.dev>
Date: Mon, 23 Sep 2024 11:49:09 +0100
Subject: [PATCH] ext4: mark fc as ineligible using an handle in
 ext4_xattr_set()

commit 04e6ce8f06d161399e5afde3df5dcfa9455b4952 upstream.

Calling ext4_fc_mark_ineligible() with a NULL handle is racy and may result
in a fast-commit being done before the filesystem is effectively marked as
ineligible.  This patch moves the call to this function so that an handle
can be used.  If a transaction fails to start, then there's not point in
trying to mark the filesystem as ineligible, and an error will eventually be
returned to user-space.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240923104909.18342-3-luis.henriques@linux.dev
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/ext4/xattr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index d94b1a6c60e27..7c35ca15571b8 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -2505,6 +2505,8 @@ ext4_xattr_set(struct inode *inode, int name_index, const char *name,
 
 		error = ext4_xattr_set_handle(handle, inode, name_index, name,
 					      value, value_len, flags);
+		ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR,
+					handle);
 		error2 = ext4_journal_stop(handle);
 		if (error == -ENOSPC &&
 		    ext4_should_retry_alloc(sb, &retries))
@@ -2512,7 +2514,6 @@ ext4_xattr_set(struct inode *inode, int name_index, const char *name,
 		if (error == 0)
 			error = error2;
 	}
-	ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR, NULL);
 
 	return error;
 }
-- 
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