From: Steven Rostedt <rostedt@goodmis.org>
To: Sam Ravnborg <sam@ravnborg.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
Steven Rostedt <srostedt@redhat.com>, Ingo Molnar <mingo@elte.hu>,
"David S. Miller" <davem@davemloft.net>,
sparclinux <sparclinux@vger.kernel.org>,
Rusty Russell <rusty@rustcorp.com.au>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH] module: clean up initialization of variable
Date: Mon, 5 Jan 2009 15:30:25 -0500 (EST) [thread overview]
Message-ID: <alpine.DEB.1.10.0901051523370.25066@gandalf.stny.rr.com> (raw)
In-Reply-To: <20090105195415.GA6204@uranus.ravnborg.org>
Impact: clean up
On Mon, 5 Jan 2009, Sam Ravnborg wrote:
>
> Fully ageed on the readability.
> I happen to trigger this as an error in the sparc code.
> But I see the same warning also in generic code.
>
> >From kernel/module.c:
> /* Suck in entire file: we'll want most of it. */
> /* vmalloc barfs on "unusual" numbers. Check here */
> if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
> return ERR_PTR(-ENOMEM);
>
>
> This gives following warning:
> kernel/module.c: In function `load_module':
> kernel/module.c:1842: warning: 'hdr' might be used uninitialized in this function
The above is caused by having the branch tracer on and the following type
of initialization:
if (x || !(y = init_me())
return;
use_me(y);
This is sloppy initialization because it initializes, not only in an
if condition, but also as the second part of a complex conditional.
This patch makes the code a bit easier to read.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Reported-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/kernel/module.c b/kernel/module.c
index 9712c52..112d6cd 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1864,7 +1864,10 @@ static noinline struct module *load_module(void __user *umod,
/* Suck in entire file: we'll want most of it. */
/* vmalloc barfs on "unusual" numbers. Check here */
- if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
+ if (len > 64 * 1024 * 1024)
+ return ERR_PTR(-ENOMEM);
+ hdr = vmalloc(len);
+ if (hdr == NULL)
return ERR_PTR(-ENOMEM);
if (copy_from_user(hdr, umod, len) != 0) {
err = -EFAULT;
next prev parent reply other threads:[~2009-01-05 20:30 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-05 18:19 ftrace breaks sparc64 build Sam Ravnborg
2009-01-05 19:31 ` Steven Rostedt
2009-01-05 19:42 ` [PATCH] sparc: make proces_ver_nack a bit more readable Steven Rostedt
2009-01-05 19:46 ` Steven Rostedt
2009-01-05 19:56 ` Steven Rostedt
2009-01-05 20:07 ` Sam Ravnborg
2009-01-05 20:08 ` Sam Ravnborg
2009-01-06 18:23 ` David Miller
2009-01-05 19:54 ` ftrace breaks sparc64 build Sam Ravnborg
2009-01-05 20:05 ` Steven Rostedt
2009-01-05 21:31 ` Sam Ravnborg
2009-01-05 21:52 ` Steven Rostedt
2009-01-05 22:01 ` Sam Ravnborg
2009-01-05 22:14 ` Steven Rostedt
2009-01-05 23:11 ` Heiko Carstens
2009-01-06 2:07 ` Steven Rostedt
2009-01-06 9:36 ` Heiko Carstens
2009-01-06 4:30 ` Steven Rostedt
2009-01-06 9:45 ` Heiko Carstens
2009-01-06 18:32 ` David Miller
2009-01-06 18:52 ` Steven Rostedt
2009-01-06 19:01 ` David Miller
2009-01-06 19:52 ` Sam Ravnborg
2009-01-06 20:02 ` David Miller
2009-01-05 20:30 ` Steven Rostedt [this message]
2009-01-05 22:59 ` [PATCH] module: clean up initialization of variable Harvey Harrison
2009-01-06 1:22 ` Rusty Russell
2009-01-06 2:02 ` Steven Rostedt
2009-01-05 19:48 ` ftrace breaks sparc64 build Al Viro
2009-01-05 19:55 ` Sam Ravnborg
2009-01-06 7:53 ` Jan Beulich
2009-01-06 11:35 ` Al Viro
2009-01-06 12:39 ` Jan Beulich
2009-01-06 13:34 ` Sam Ravnborg
2009-01-06 15:52 ` Al Viro
2009-01-06 18:39 ` David Miller
2009-01-08 9:28 ` Jan Beulich
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=alpine.DEB.1.10.0901051523370.25066@gandalf.stny.rr.com \
--to=rostedt@goodmis.org \
--cc=akpm@linux-foundation.org \
--cc=davem@davemloft.net \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=rusty@rustcorp.com.au \
--cc=sam@ravnborg.org \
--cc=sparclinux@vger.kernel.org \
--cc=srostedt@redhat.com \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).