From nobody Sun May 24 21:40:05 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A60E32F748; Thu, 21 May 2026 07:49:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779349796; cv=none; b=WdwvdbMo9WYFi7rc99Z616EXO/CiOavSrKm9SnWMHgBV53zxwisXpRTbiONiMdKNJiQrV69Rh0eEsbzjN5Uq341PEwTQZtE1vUnA2/sRJf6Izz/gKy9fWzbWUBUeLzvC+5/du4SDi80JLmf9hLG1olfqJ4xHXwLPJDDgssE7vS8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779349796; c=relaxed/simple; bh=PicYSaJ/qBBNG0nwnN5yBf7cuvcJTD9f+P4T2OeYfPM=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=F2CKEkr7UQmb9b8rkf8tAWjxuG8iHb/vQBC7Il/E4ygVpVawUdhwlIZVDGYD0WMkYrl9rWCOte055MNdGhQvvPd/B2yzrmllZDmMImsX6jSQobEtwq/0jXYmkZ71gFlZDZfkiCPNq4kBlGnGY8o2/BFdC6CU0SWUVKsty5iwUDQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: 9e46e66254e911f1aa26b74ffac11d73-20260521 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:c49ba0f4-8279-482d-b201-1e1a9eab771c,IP:0,U RL:0,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:-5 X-CID-META: VersionHash:e7bac3a,CLOUDID:95a0b5a71b1439e7c2a113c3a87243ee,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:102|850|865|898,TC:nil,Content:0|15|50,E DM:-3,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA :0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 9e46e66254e911f1aa26b74ffac11d73-20260521 X-User: zenghongling@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1010667280; Thu, 21 May 2026 15:49:38 +0800 From: Hongling Zeng To: viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, thomas.weissschuh@linutronix.de Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, zhongling0719@126.com, Hongling Zeng , stable@vger.kernel.org Subject: [PATCH] fs: Fix lock leak in replace_fd() Date: Thu, 21 May 2026 15:49:34 +0800 Message-Id: <20260521074934.49256-1-zenghongling@kylinos.cn> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" In replace_fd(), the function acquires files->file_lock but then has two return paths that don't release the lock: - When do_dup2() fails (returns negative error) - When do_dup2() succeeds (returns 0) Both of these paths return directly without unlocking files->file_lock, causing a lock leak and potential deadlock. Fix this by making both error and success paths go through the out_unlock label to ensure the lock is always released. Fixes: 708c04a5c2b7 ("fs: always return zero on success from replace_fd()") Cc: stable@vger.kernel.org Signed-off-by: Hongling Zeng --- fs/file.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/file.c b/fs/file.c index 2c81c0b162d0..d0f019fb0568 100644 --- a/fs/file.c +++ b/fs/file.c @@ -1361,8 +1361,7 @@ int replace_fd(unsigned fd, struct file *file, unsign= ed flags) goto out_unlock; err =3D do_dup2(files, file, fd, flags); if (err < 0) - return err; - return 0; + goto out_unlock; =20 out_unlock: spin_unlock(&files->file_lock); --=20 2.25.1