From patchwork Wed Mar 5 10:08:12 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 14002270 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 554781C8612 for ; Wed, 5 Mar 2025 10:08:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741169311; cv=none; b=F+FARfu6A3lqQimOVsmRqwu5yW+alM5CMT+1xC856SFLbXbQcwjJ+s3CEHuS22D2cfHXF50PpUl61EklLbNMTUF+zI5Jgov2o1wBUq4U/QYe+D25tF9ftPiveSC8CCFcUmq2G+8NdGEy9wSTLEAxW+2CJvtfv37yHIvLh/CPKHQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741169311; c=relaxed/simple; bh=av4DkB7WFvAYLnrOfF/XuXugIucHUQhRFCeRNgZsKuk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Ujn7e633ODIilC2GvVYp08baAl3F1vfDVdz5Jg11uVvPzPw35NS+d12KrJLez6eJQEfdsR6MfpUTvuMGtBpqVOJVZ1nwAsXDlpTloV+dPQ4JpgTMgRAlhtGfBHOwr4PE1F0MsKFHbn0+7qi6l1+EgVYArMLGbO1n54muu4EcEMg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rSs02nA/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rSs02nA/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4E9B4C4CEEE; Wed, 5 Mar 2025 10:08:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741169310; bh=av4DkB7WFvAYLnrOfF/XuXugIucHUQhRFCeRNgZsKuk=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=rSs02nA/ylmlAJdDufAbmHCiv402qUeeLAoA9M1rJycbH/QXgJrzD6KpzGqLn1Fzp KW3Vqk66KBff+Oos9PNJCdZfZNDDOB30HbIH/Ub2jPc45gHMTNgY8W853XXrzje+7R ZjUh4BJ2YrtS6BHVBYZPY6baP6F+XYHZI/vhD9mG17vtMqxwTYe3mz2lW1/+pVQWhr NZAWOzUPiSGcNk1VeZL1S4kPjuMfcyomOqlUlU0TOuKyz+AfjBOzyrO0TrnFAugJVQ rTli0zPvmvxvF0nkgfu+KaItjww/oUw1pcrQfismjLwRS4/lQ+yHXlSWf1WjecW2vL onfeWoiHFV0ew== From: Christian Brauner Date: Wed, 05 Mar 2025 11:08:12 +0100 Subject: [PATCH v3 02/16] pidfd: rely on automatic cleanup in __pidfd_prepare() Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250305-work-pidfs-kill_on_last_close-v3-2-c8c3d8361705@kernel.org> References: <20250305-work-pidfs-kill_on_last_close-v3-0-c8c3d8361705@kernel.org> In-Reply-To: <20250305-work-pidfs-kill_on_last_close-v3-0-c8c3d8361705@kernel.org> To: Oleg Nesterov Cc: linux-fsdevel@vger.kernel.org, Jeff Layton , Lennart Poettering , Daan De Meyer , Mike Yuan , Christian Brauner X-Mailer: b4 0.15-dev-42535 X-Developer-Signature: v=1; a=openpgp-sha256; l=1287; i=brauner@kernel.org; h=from:subject:message-id; bh=av4DkB7WFvAYLnrOfF/XuXugIucHUQhRFCeRNgZsKuk=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaSfUJoh4Ghx5uW8wivPX0XYsP33qG/f0yw2IfBwwGu2v 3ZfHXdKdpSyMIhxMciKKbI4tJuEyy3nqdhslKkBM4eVCWQIAxenAExkmjYjw/FFa47PyBXgl9Eq vTb5h4yxg1161OGOF+J2jb8TwkXXH2f4zfL3iS9jzoN6oWUzLwUnrVqUU7iKKUmB/913u4Jun8I T/AA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Rely on scope-based cleanup for the allocated file descriptor. Link: https://lore.kernel.org/r/20250304-work-pidfs-kill_on_last_close-v2-2-44fdacfaa7b7@kernel.org Acked-by: Jeff Layton Signed-off-by: Christian Brauner --- kernel/fork.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 735405a9c5f3..6230f5256bc5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2032,25 +2032,23 @@ static inline void rcu_copy_process(struct task_struct *p) */ static int __pidfd_prepare(struct pid *pid, unsigned int flags, struct file **ret) { - int pidfd; struct file *pidfd_file; - pidfd = get_unused_fd_flags(O_CLOEXEC); + CLASS(get_unused_fd, pidfd)(O_CLOEXEC); if (pidfd < 0) return pidfd; pidfd_file = pidfs_alloc_file(pid, flags | O_RDWR); - if (IS_ERR(pidfd_file)) { - put_unused_fd(pidfd); + if (IS_ERR(pidfd_file)) return PTR_ERR(pidfd_file); - } + /* * anon_inode_getfile() ignores everything outside of the * O_ACCMODE | O_NONBLOCK mask, set PIDFD_THREAD manually. */ pidfd_file->f_flags |= (flags & PIDFD_THREAD); *ret = pidfd_file; - return pidfd; + return take_fd(pidfd); } /**