LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Paul Moore <pmoore@redhat.com>
To: linux-fsdevel@vger.kernel.org, linux-audit@redhat.com
Cc: rgb@redhat.com, sd@queasysnail.net, linux-kernel@vger.kernel.org,
	linux@roeck-us.net, viro@zeniv.linux.org.uk
Subject: [PATCH v2 1/5] fs: rework getname_kernel to handle up to PATH_MAX sized filenames
Date: Wed, 21 Jan 2015 23:59:56 -0500	[thread overview]
Message-ID: <20150122045956.1347.11508.stgit@localhost> (raw)
In-Reply-To: <20150122045303.1347.98054.stgit@localhost>

In preparation for expanded use in the kernel, make getname_kernel()
more useful by allowing it to handle any legal filename length.

Thanks to Guenter Roeck for his suggestion to substitute memcpy() for
strlcpy().

CC: linux@roeck-us.net
CC: viro@zeniv.linux.org.uk
CC: linux-fsdevel@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
---
 fs/namei.c |   34 ++++++++++++++++++++--------------
 1 file changed, 20 insertions(+), 14 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 9eb787e..63eaaf6 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -211,32 +211,38 @@ getname(const char __user * filename)
 	return getname_flags(filename, 0, NULL);
 }
 
-/*
- * The "getname_kernel()" interface doesn't do pathnames longer
- * than EMBEDDED_NAME_MAX. Deal with it - you're a kernel user.
- */
 struct filename *
 getname_kernel(const char * filename)
 {
 	struct filename *result;
-	char *kname;
-	int len;
-
-	len = strlen(filename);
-	if (len >= EMBEDDED_NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
+	int len = strlen(filename) + 1;
 
 	result = __getname();
 	if (unlikely(!result))
 		return ERR_PTR(-ENOMEM);
 
-	kname = (char *)result + sizeof(*result);
-	result->name = kname;
+	if (len <= EMBEDDED_NAME_MAX) {
+		result->name = (char *)(result) + sizeof(*result);
+		result->separate = false;
+	} else if (len <= PATH_MAX) {
+		struct filename *tmp;
+
+		tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+		if (unlikely(!tmp)) {
+			__putname(result);
+			return ERR_PTR(-ENOMEM);
+		}
+		tmp->name = (char *)result;
+		tmp->separate = true;
+		result = tmp;
+	} else {
+		__putname(result);
+		return ERR_PTR(-ENAMETOOLONG);
+	}
+	memcpy((char *)result->name, filename, len);
 	result->uptr = NULL;
 	result->aname = NULL;
-	result->separate = false;
 
-	strlcpy(kname, filename, EMBEDDED_NAME_MAX);
 	return result;
 }
 


  reply	other threads:[~2015-01-22  5:00 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-22  4:59 [PATCH v2 0/5] Overhaul the audit filename handling Paul Moore
2015-01-22  4:59 ` Paul Moore [this message]
2015-01-22 15:53   ` [PATCH v2 1/5] fs: rework getname_kernel to handle up to PATH_MAX sized filenames Richard Guy Briggs
2015-01-22 16:56     ` Guenter Roeck
2015-01-22  5:00 ` [PATCH v2 2/5] fs: create proper filename objects using getname_kernel() Paul Moore
2015-01-22 15:54   ` Richard Guy Briggs
2015-01-22  5:00 ` [PATCH v2 3/5] audit: enable filename recording via getname_kernel() Paul Moore
2015-01-22  5:00 ` [PATCH v2 4/5] audit: fix filename matching in __audit_inode() and __audit_inode_child() Paul Moore
2015-01-22 16:04   ` Richard Guy Briggs
2015-01-22  5:00 ` [PATCH v2 5/5] audit: replace getname()/putname() hacks with reference counters Paul Moore
2015-01-22 16:09   ` Richard Guy Briggs
2015-01-22 16:24     ` Paul Moore
2015-01-22  5:36 ` [PATCH v2 0/5] Overhaul the audit filename handling Guenter Roeck
2015-01-22  7:54   ` Al Viro
2015-01-22 16:23     ` Paul Moore
2015-01-22 21:25       ` Paul Moore
2015-01-22 21:29         ` Al Viro
2015-01-22 21:40           ` Al Viro
2015-01-22 22:05             ` Paul Moore
2015-01-23  5:30             ` Al Viro
2015-01-23 16:15               ` Paul Moore
2015-01-24  9:03               ` Sedat Dilek
2015-01-24 22:54                 ` Stephen Rothwell
2015-01-26 15:52                 ` Paul Moore
2015-01-22 17:13     ` Guenter Roeck
2015-01-22 16:22   ` Paul Moore
2015-01-22 16:58     ` Guenter Roeck

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20150122045956.1347.11508.stgit@localhost \
    --to=pmoore@redhat.com \
    --cc=linux-audit@redhat.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=rgb@redhat.com \
    --cc=sd@queasysnail.net \
    --cc=viro@zeniv.linux.org.uk \
    --subject='Re: [PATCH v2 1/5] fs: rework getname_kernel to handle up to PATH_MAX sized filenames' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).