From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (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 32E57224AF1; Sat, 29 Nov 2025 17:01:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764435699; cv=none; b=rPuN3M2LRnshZcblwfHHiY5RmOVO+enczEc1aahSPFWoZvCFFc6AGxsTtwaJPsGbHVCLvNDnDrmPKYB7GDyYFO7babXC2una0nmlDULnCYWplmEiNSnA7nwkr1V62R7sDy31btStGYNT5kQwZc3w4mpDj6tFtt96fWDKUIYND5k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764435699; c=relaxed/simple; bh=0YgR4JPIv4trQtTKKjsZyS87DZYBNKhfp3ECxkZq4Jk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KHUrvfaFiC8CkG9PhEid5Y671dlm6XsZC6svYgnhQLv75Gy9Y+8i1F02gHzEzDThZ+smG72mW2xBgoRLykZRd7jBKkXYgTLurvYg1X+bhfLd1nbdzBiupei0wVI3jm7D43dvRoA/yzBH5GCRAlq7VlPHc3fMzkRKtDIqwj8zUkI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=nk5LWx5c; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="nk5LWx5c" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=rf0QBWjyFpio5L0bss+WOUIUsJ9vjsc4nuTYKt2zUvY=; b=nk5LWx5ctZD1BBYKyofwqyqFv8 XIl2TlES11lqi/W5/bA3lw52NmuG0HbqvSAVkmRSeIJ7sGOi5XJukyWeUPN+SNDpClEoPIADZnNh1 nJqkYcutyYhTqyLWAKjvqXiTgmvLgdxOrW76mFXPEc5tF14eTWlkaHyClGRDCyDKvO+/TgK6LXMqT lNEbS+lCGkfY3yMlyXJfSxkjGZZzOS86IBNHhx4DhCVvzsAg87HL7G5PUeSMGljXvkBuZoeE6V/DL egq9mWLNr2EbJ64knTcWNvX9QYUfi1ESAM+94ioLKAuo/dB217uG9L8oFHyVcKIv6ZOKIN7uKibOG 87/FXaHA==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.99 #2 (Red Hat Linux)) id 1vPOKM-00000000dCK-3X1S; Sat, 29 Nov 2025 17:01:42 +0000 From: Al Viro To: linux-fsdevel@vger.kernel.org Cc: torvalds@linux-foundation.org, brauner@kernel.org, jack@suse.cz, mjguzik@gmail.com, paul@paul-moore.com, axboe@kernel.dk, audit@vger.kernel.org, io-uring@vger.kernel.org Subject: [RFC PATCH v2 03/18] do_fchownat(): import pathname only once Date: Sat, 29 Nov 2025 17:01:27 +0000 Message-ID: <20251129170142.150639-4-viro@zeniv.linux.org.uk> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251129170142.150639-1-viro@zeniv.linux.org.uk> References: <20251129170142.150639-1-viro@zeniv.linux.org.uk> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: Al Viro Convert the user_path_at() call inside a retry loop into getname_flags() + filename_lookup() + putname() and leave only filename_lookup() inside the loop. Since we have the default logics for use of LOOKUP_EMPTY (passed iff AT_EMPTY_PATH is present in flags), just use getname_uflags() and don't bother with setting LOOKUP_EMPTY in lookup_flags - getname_uflags() will pass the right thing to getname_flags() and filename_lookup() doesn't care about LOOKUP_EMPTY at all. The things could be further simplified by use of cleanup.h stuff, but let's not clutter the patch with that. Signed-off-by: Al Viro --- fs/open.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/open.c b/fs/open.c index e9a08a820e49..e5110f5e80c7 100644 --- a/fs/open.c +++ b/fs/open.c @@ -804,17 +804,17 @@ int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, int flag) { struct path path; - int error = -EINVAL; + int error; int lookup_flags; + struct filename *name; if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) - goto out; + return -EINVAL; lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; - if (flag & AT_EMPTY_PATH) - lookup_flags |= LOOKUP_EMPTY; + name = getname_uflags(filename, flag); retry: - error = user_path_at(dfd, filename, lookup_flags, &path); + error = filename_lookup(dfd, name, lookup_flags, &path, NULL); if (error) goto out; error = mnt_want_write(path.mnt); @@ -829,6 +829,7 @@ int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, goto retry; } out: + putname(name); return error; } -- 2.47.3