From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794590718; b=aZGwFId5d3wVu/36xW8gwspB6sS/ITbIVU1uhz/3Dgf63ZUJS8Rf8V8FiAlF3JdL17Dp RaP0srGFmr3Sb6ecNeTh707mq6r54Eex1vzbvqYRYafKySs0v/v5sKYk9WoEKC9yvpq1s YA05R9X216BI0mxuDi5Q5QPPdg3XI2X6iJUnFVu4GnMwt5lyqrb8ljvhrg5JBuDZDVBgx P/4xueoWQeXyg71Ew9fgTUYCgC+FRPi/6JNbgH7R3u8nS6UZ7H2rlZFnHsFz3w70pN2q6 elFxVBirjTUibmwVXCncjb+ilx6ePiJQnk28JObxUmSMUVtptyxsRqORuJ7GZa34NqA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794590718; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=f266gsDDF/plXmo0V8XsMax73EYqH0BNjgAvFWJ01e0=; b=r3E96EcwyL8KSwYNumaDZZY7jBzw5AQLFQveKyKDDz2woXdkX/qfGfkryc8M0egqJkdt 3gzVE00D7gxcwF3OtcXX01FHydl00v00v64BJTfXm0fnhkViv1HkXU1SdIet+iOXLrruZ PiQwihdYYtFFZG5wlSTAwlR7wcJ7aKIHfh93+kSkCDHNIcsuKUhF2WJYeLQ8bQdVMr7fw sFaMqb5of90GGG8bT7Q8b6PawzcfYDEKDb7BqVwDHymTbEZY1GLYel6jdiOKT/v8UyoMz ywpqSbTc8vNnhAseCVDK1uhRcSgjjOJ5fHf4C3rIn4GPYky4hlNiOlqfaZMWdAy2jPA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=bB9wnQ3v; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75BAA606B23A; Fri, 13 Nov 2026 17:25:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=bB9wnQ3v Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2218F1F000C4; Fri, 13 Nov 2026 17:25:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794590718; bh=f266gsDDF/plXmo0V8XsMax73EYqH0BNjgAvFWJ01e0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bB9wnQ3vudlyUNn0l2rTuXJ+MzEK9t5xgvcm3g2ni64CWUlJa5+A8a7fOwVQuLB7B jnNzeaRTudq3xBafpVLSSkok4i2zqZh5rYHmq3oazcho2QqX6jkqBqpwcLfhtOHRgd RepOFeJkles2wqqYzlkGS1VEyD6VBQWWZiTL6mrs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mateusz Guzik , Christian Brauner , Sasha Levin Subject: [PATCH 6.18 625/686] fs: assert on ->i_count in iput_final() Date: Fri, 13 Nov 2026 10:52:38 -0500 Message-ID: <20261113153843.029959936@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153820.902362109@linuxfoundation.org> References: <20261113153820.902362109@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mateusz Guzik [ Upstream commit be97a4b63ca8c3ed8f5c3f5606a15a8379c78afb ] Notably make sure the count is 0 after the return from ->drop_inode(), provided we are going to drop. Inspired by suspicious games played by f2fs. Signed-off-by: Mateusz Guzik Signed-off-by: Christian Brauner Stable-dep-of: 8ee09f597763 ("fs: rotate inodes whose page cache could not be dropped") Signed-off-by: Sasha Levin --- fs/inode.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/inode.c b/fs/inode.c index 24762fd1f2f77..acf09822535ed 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1875,6 +1875,7 @@ static void iput_final(struct inode *inode) int drop; WARN_ON(inode->i_state & I_NEW); + VFS_BUG_ON_INODE(atomic_read(&inode->i_count) != 0, inode); if (op->drop_inode) drop = op->drop_inode(inode); @@ -1889,6 +1890,12 @@ static void iput_final(struct inode *inode) return; } + /* + * Re-check ->i_count in case the ->drop_inode() hooks played games. + * Note we only execute this if the verdict was to drop the inode. + */ + VFS_BUG_ON_INODE(atomic_read(&inode->i_count) != 0, inode); + state = inode->i_state; if (!drop) { WRITE_ONCE(inode->i_state, state | I_WILL_FREE); -- 2.53.0