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 185A31E5B95; Mon, 22 Sep 2025 03:52:25 +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=1758513149; cv=none; b=ftXIb5JVm4oObAFtvZUXpGhhejvVuzrn6JzRcgNZNVTmDz8gj4zK89Qk8xzu6QXaN9b+wumReopLkd28KywIkUc4CAKQoT/HzMyM0OA0vLbvzWsLhY5nRi+1VViU9okGUlTyokJ0m2mNKOaifC+qKVNurY0zqmIr5JPeoD6gN9s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758513149; c=relaxed/simple; bh=a3OsQPqz/vBcdO71IrFI1O5gAfjMbOy5wWLMX/HC7jI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pgEiodK/TigfDVnWT+qxdrU3JsNTiyVh0sbM6E8Vwz57etZEp9mPbOwJ2lTkCGmwBeHE2YryP8iPjXS/Y1PUi/iGMpmQRI5SgwwHS9ERAnPBi9nq2JcK7l8UqxdRsnv4DLCjVjfYSf6J+j+RllKKqdkZslVIUAoXEVXKqxsVVFs= 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=HRIQZ+mv; 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="HRIQZ+mv" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=uvOBcE6UQrpI6WGthIQ2mhhrrb+ib1iPppy0esW2pF8=; b=HRIQZ+mv3XjEr5HE95zUXo4+a6 NSRxPd0KrHJeiO55wmL8zxyLexKaYOtukTqYDUk4P7Wms504VRDpnu79qCxm9LPPLIvXhPbJDCS9J YRDvUR+wf4nDqbVfzd55z89ZBt+992gTBdYH/kADhegMyk3HdwQFQNcaBQPMTq94apRnfURggWfW/ JHqnvLMVP0BaRB8Hc5glF+yhqEgLGpQ51cjWLVzIBoXc/Te8IX6AprfxOgc+nyojcMBMgjxAohGXS cfa+R9tgKpxmrTagksJYExY1jTrB11KyU7eGcwAdbKgV4ytOY8lJPggIhRGBTZNeJw+hKdXevicaO 50y2/Udw==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1v0Xb8-00000007I6X-2KnX; Mon, 22 Sep 2025 03:52:18 +0000 Date: Mon, 22 Sep 2025 04:52:18 +0100 From: Al Viro To: Paul Moore Cc: linux-fsdevel@vger.kernel.org, torvalds@linux-foundation.org, brauner@kernel.org, jack@suse.cz, raven@themaw.net, miklos@szeredi.hu, a.hindborg@kernel.org, linux-mm@kvack.org, linux-efi@vger.kernel.org, ocfs2-devel@lists.linux.dev, kees@kernel.org, rostedt@goodmis.org, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, casey@schaufler-ca.com, linuxppc-dev@lists.ozlabs.org, borntraeger@linux.ibm.com Subject: Re: [PATCH 31/39] convert selinuxfs Message-ID: <20250922035218.GP39973@ZenIV> References: <20250920074156.GK39973@ZenIV> <20250920074759.3564072-1-viro@zeniv.linux.org.uk> <20250920074759.3564072-31-viro@zeniv.linux.org.uk> <20250921222619.GO39973@ZenIV> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Al Viro On Sun, Sep 21, 2025 at 10:50:02PM -0400, Paul Moore wrote: > Looks good to me, ACK below. For me personally, it's a bit late to > take non-bugfix stuff for the upcoming merge window so I would defer > this for a few weeks, but if you want to take it now that's your call. > Also your call if you would prefer this to go in with the rest of the > patchset you've working on, or if you want me to take it via the > SELinux tree. Let me know. Seeing that it's already a 41-commit patchset (rpc_pipe conversion pulled in, now +1 from this split) with several more in the pipeline (securityfs conversion, for starters) and it's -rc7... I think I'll post v2 in the middle of the week, but aim for the next cycle. Rebase to -rc1 as soon as it comes, post v3 for review and testing, then shove it into -next. Especially since #work.nfsctl is in -next, so hopefully by -rc1 there won't be any need to put merges in the middle of the series, with conversion of nfsctl included into the series, bringing with it removal of kill_litter_super() and (hopefully) "give configfs and apparmorfs private copies of simple_unlink() and simple_rmdir() doing dput() instead of d_make_discardable(), then make d_make_discardable() complain about being called on non-persistent dentries". Speaking of additional patches into that series: AFAICS there's no reason for selinuxfs to allocate dentry before the inode. Doing it the other way round simplifies the things quite a bit, IMO. Something like this (as followup to the previous patch): diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 482a2cac9640..7bee2d8bdec5 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -1197,6 +1197,25 @@ static struct inode *sel_make_inode(struct super_block *sb, umode_t mode) return ret; } +static struct dentry *sel_attach(struct dentry *parent, const char *name, + struct inode *inode) +{ + struct dentry *dentry = d_alloc_name(parent, name); + if (unlikely(!dentry)) { + iput(inode); + return ERR_PTR(-ENOMEM); + } + d_add(dentry, inode); + return dentry; +} + +static int sel_attach_file(struct dentry *parent, const char *name, + struct inode *inode) +{ + struct dentry *dentry = sel_attach(parent, name, inode); + return PTR_ERR_OR_ZERO(dentry); +} + static ssize_t sel_read_bool(struct file *filep, char __user *buf, size_t count, loff_t *ppos) { @@ -1364,8 +1383,7 @@ static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_ *bool_num = num; *bool_pending_names = names; - for (i = 0; i < num; i++) { - struct dentry *dentry; + for (i = 0; !ret && i < num; i++) { struct inode *inode; struct inode_security_struct *isec; ssize_t len; @@ -1376,15 +1394,9 @@ static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_ ret = -ENAMETOOLONG; break; } - dentry = d_alloc_name(bool_dir, names[i]); - if (!dentry) { - ret = -ENOMEM; - break; - } inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); if (!inode) { - dput(dentry); ret = -ENOMEM; break; } @@ -1402,7 +1414,8 @@ static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_ isec->initialized = LABEL_INITIALIZED; inode->i_fop = &sel_bool_ops; inode->i_ino = i|SEL_BOOL_INO_OFFSET; - d_add(dentry, inode); + + ret = sel_attach_file(bool_dir, names[i], inode); } out: free_page((unsigned long)page); @@ -1587,6 +1600,7 @@ static int sel_make_avc_files(struct dentry *dir) struct super_block *sb = dir->d_sb; struct selinux_fs_info *fsi = sb->s_fs_info; unsigned int i; + int err = 0; static const struct tree_descr files[] = { { "cache_threshold", &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, @@ -1596,26 +1610,20 @@ static int sel_make_avc_files(struct dentry *dir) #endif }; - for (i = 0; i < ARRAY_SIZE(files); i++) { + for (i = 0; !err && i < ARRAY_SIZE(files); i++) { struct inode *inode; - struct dentry *dentry; - - dentry = d_alloc_name(dir, files[i].name); - if (!dentry) - return -ENOMEM; inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); - if (!inode) { - dput(dentry); + if (!inode) return -ENOMEM; - } inode->i_fop = files[i].ops; inode->i_ino = ++fsi->last_ino; - d_add(dentry, inode); + + err = sel_attach_file(dir, files[i].name, inode); } - return 0; + return err; } static int sel_make_ss_files(struct dentry *dir) @@ -1623,30 +1631,25 @@ static int sel_make_ss_files(struct dentry *dir) struct super_block *sb = dir->d_sb; struct selinux_fs_info *fsi = sb->s_fs_info; unsigned int i; + int err = 0; static const struct tree_descr files[] = { { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO }, }; - for (i = 0; i < ARRAY_SIZE(files); i++) { + for (i = 0; !err && i < ARRAY_SIZE(files); i++) { struct inode *inode; - struct dentry *dentry; - - dentry = d_alloc_name(dir, files[i].name); - if (!dentry) - return -ENOMEM; inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); - if (!inode) { - dput(dentry); + if (!inode) return -ENOMEM; - } inode->i_fop = files[i].ops; inode->i_ino = ++fsi->last_ino; - d_add(dentry, inode); + + err = sel_attach_file(dir, files[i].name, inode); } - return 0; + return err; } static ssize_t sel_read_initcon(struct file *file, char __user *buf, @@ -1674,30 +1677,25 @@ static const struct file_operations sel_initcon_ops = { static int sel_make_initcon_files(struct dentry *dir) { unsigned int i; + int err = 0; - for (i = 1; i <= SECINITSID_NUM; i++) { - struct inode *inode; - struct dentry *dentry; + for (i = 1; !err && i <= SECINITSID_NUM; i++) { const char *s = security_get_initial_sid_context(i); + struct inode *inode; if (!s) continue; - dentry = d_alloc_name(dir, s); - if (!dentry) - return -ENOMEM; inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); - if (!inode) { - dput(dentry); + if (!inode) return -ENOMEM; - } inode->i_fop = &sel_initcon_ops; inode->i_ino = i|SEL_INITCON_INO_OFFSET; - d_add(dentry, inode); + err = sel_attach_file(dir, s, inode); } - return 0; + return err; } static inline unsigned long sel_class_to_ino(u16 class) @@ -1779,29 +1777,21 @@ static int sel_make_perm_files(struct selinux_policy *newpolicy, if (rc) return rc; - for (i = 0; i < nperms; i++) { + for (i = 0; !rc && i < nperms; i++) { struct inode *inode; - struct dentry *dentry; - rc = -ENOMEM; - dentry = d_alloc_name(dir, perms[i]); - if (!dentry) - goto out; - - rc = -ENOMEM; inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); if (!inode) { - dput(dentry); - goto out; + rc = -ENOMEM; + break; } inode->i_fop = &sel_perm_ops; /* i+1 since perm values are 1-indexed */ inode->i_ino = sel_perm_to_ino(classvalue, i + 1); - d_add(dentry, inode); + + rc = sel_attach_file(dir, perms[i], inode); } - rc = 0; -out: for (i = 0; i < nperms; i++) kfree(perms[i]); kfree(perms); @@ -1816,20 +1806,18 @@ static int sel_make_class_dir_entries(struct selinux_policy *newpolicy, struct selinux_fs_info *fsi = sb->s_fs_info; struct dentry *dentry = NULL; struct inode *inode = NULL; - - dentry = d_alloc_name(dir, "index"); - if (!dentry) - return -ENOMEM; + int err; inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); - if (!inode) { - dput(dentry); + if (!inode) return -ENOMEM; - } inode->i_fop = &sel_class_ops; inode->i_ino = sel_class_to_ino(index); - d_add(dentry, inode); + + err = sel_attach_file(dir, "index", inode); + if (err) + return err; dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino); if (IS_ERR(dentry)) @@ -1881,58 +1869,47 @@ static int sel_make_policycap(struct dentry *dir) { struct super_block *sb = dir->d_sb; unsigned int iter; - struct dentry *dentry = NULL; struct inode *inode = NULL; + int err = 0; + + for (iter = 0; !err && iter <= POLICYDB_CAP_MAX; iter++) { + const char *name; - for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) { if (iter < ARRAY_SIZE(selinux_policycap_names)) - dentry = d_alloc_name(dir, - selinux_policycap_names[iter]); + name = selinux_policycap_names[iter]; else - dentry = d_alloc_name(dir, "unknown"); - - if (dentry == NULL) - return -ENOMEM; + name = "unknown"; inode = sel_make_inode(sb, S_IFREG | 0444); - if (inode == NULL) { - dput(dentry); + if (!inode) return -ENOMEM; - } inode->i_fop = &sel_policycap_ops; inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; - d_add(dentry, inode); + err = sel_attach_file(dir, name, inode); } - return 0; + return err; } static struct dentry *sel_make_dir(struct dentry *dir, const char *name, unsigned long *ino) { - struct dentry *dentry = d_alloc_name(dir, name); struct inode *inode; - if (!dentry) - return ERR_PTR(-ENOMEM); - inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO); - if (!inode) { - dput(dentry); + if (!inode) return ERR_PTR(-ENOMEM); - } inode->i_op = &simple_dir_inode_operations; inode->i_fop = &simple_dir_operations; inode->i_ino = ++(*ino); /* directory inodes start off with i_nlink == 2 (for "." entry) */ inc_nlink(inode); - d_add(dentry, inode); /* bump link count on parent directory, too */ inc_nlink(d_inode(dir)); - return dentry; + return sel_attach(dir, name, inode); } static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask) @@ -2020,17 +1997,10 @@ static int sel_fill_super(struct super_block *sb, struct fs_context *fc) goto err; } - ret = -ENOMEM; - dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); - if (!dentry) - goto err; - ret = -ENOMEM; inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); - if (!inode) { - dput(dentry); + if (!inode) goto err; - } inode->i_ino = ++fsi->last_ino; isec = selinux_inode(inode); @@ -2039,7 +2009,9 @@ static int sel_fill_super(struct super_block *sb, struct fs_context *fc) isec->initialized = LABEL_INITIALIZED; init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); - d_add(dentry, inode); + ret = sel_attach_file(sb->s_root, NULL_FILE_NAME, inode); + if (ret) + goto err; dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino); if (IS_ERR(dentry)) {