2008-10-20 06:14:46

by Krishna Kumar2

Subject: [PATCH 2/4] nfsd: Drop reference in expkey_parse error cases

From: Krishna Kumar <[email protected]>

Drop reference to export key on error. Compile tested.

Signed-off-by: Krishna Kumar <[email protected]>
---
fs/nfsd/export.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff -ruNp linux-2.6.27.org/fs/nfsd/export.c linux-2.6.27.new/fs/nfsd/export.c
--- linux-2.6.27.org/fs/nfsd/export.c 2008-10-20 10:47:18.000000000 +0530
+++ linux-2.6.27.new/fs/nfsd/export.c 2008-10-20 10:48:36.000000000 +0530
@@ -151,8 +151,10 @@ static int expkey_parse(struct cache_det

/* now we want a pathname, or empty meaning NEGATIVE */
err = -EINVAL;
- if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0)
+ if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0) {
+ cache_put(&ek->h, &svc_expkey_cache);
goto out;
+ }
dprintk("Path seems to be <%s>\n", buf);
err = 0;
if (len == 0) {
@@ -164,8 +166,10 @@ static int expkey_parse(struct cache_det
} else {
struct nameidata nd;
err = path_lookup(buf, 0, &nd);
- if (err)
+ if (err) {
+ cache_put(&ek->h, &svc_expkey_cache);
goto out;
+ }

dprintk("Found the path %s\n", buf);
key.ek_path = nd.path;

2008-10-20 20:53:23

by J. Bruce Fields

Subject: Re: [PATCH 2/4] nfsd: Drop reference in expkey_parse error cases

On Mon, Oct 20, 2008 at 11:44:40AM +0530, Krishna Kumar wrote:
> From: Krishna Kumar <[email protected]>
>
> Drop reference to export key on error. Compile tested.

Looks correct, thanks! But adding the export key cleanup to every "goto
out" is getting a little silly; I've applied your patch, then applied
the cleanup appended below.

--b.

> Signed-off-by: Krishna Kumar <[email protected]>
> ---
> fs/nfsd/export.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff -ruNp linux-2.6.27.org/fs/nfsd/export.c linux-2.6.27.new/fs/nfsd/export.c
> --- linux-2.6.27.org/fs/nfsd/export.c 2008-10-20 10:47:18.000000000 +0530
> +++ linux-2.6.27.new/fs/nfsd/export.c 2008-10-20 10:48:36.000000000 +0530
> @@ -151,8 +151,10 @@ static int expkey_parse(struct cache_det
>
> /* now we want a pathname, or empty meaning NEGATIVE */
> err = -EINVAL;
> - if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0)
> + if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0) {
> + cache_put(&ek->h, &svc_expkey_cache);
> goto out;
> + }
> dprintk("Path seems to be <%s>\n", buf);
> err = 0;
> if (len == 0) {
> @@ -164,8 +166,10 @@ static int expkey_parse(struct cache_det
> } else {
> struct nameidata nd;
> err = path_lookup(buf, 0, &nd);
> - if (err)
> + if (err) {
> + cache_put(&ek->h, &svc_expkey_cache);
> goto out;
> + }
>
> dprintk("Found the path %s\n", buf);
> key.ek_path = nd.path;
> --

commit 0264a42d6b12afaaa39dbf407655bb49ed828a1e
Author: J. Bruce Fields <[email protected]>
Date: Mon Oct 20 16:34:21 2008 -0400

nfsd: clean up expkey_parse error cases

We might as well do all of these at the end. Fix up a couple minor
style nits while we're there.

Signed-off-by: J. Bruce Fields <[email protected]>

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 7ce2c6e..5cd882b 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -99,7 +99,7 @@ static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
int fsidtype;
char *ep;
struct svc_expkey key;
- struct svc_expkey *ek;
+ struct svc_expkey *ek = NULL;

if (mesg[mlen-1] != '\n')
return -EINVAL;
@@ -107,7 +107,8 @@ static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)

buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
err = -ENOMEM;
- if (!buf) goto out;
+ if (!buf)
+ goto out;

err = -EINVAL;
if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
@@ -151,38 +152,34 @@ static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)

/* now we want a pathname, or empty meaning NEGATIVE */
err = -EINVAL;
- if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0) {
- cache_put(&ek->h, &svc_expkey_cache);
+ len = qword_get(&mesg, buf, PAGE_SIZE);
+ if (len < 0)
goto out;
- }
dprintk("Path seems to be <%s>\n", buf);
err = 0;
if (len == 0) {
set_bit(CACHE_NEGATIVE, &key.h.flags);
ek = svc_expkey_update(&key, ek);
- if (ek)
- cache_put(&ek->h, &svc_expkey_cache);
- else err = -ENOMEM;
+ if (!ek)
+ err = -ENOMEM;
} else {
struct nameidata nd;
err = path_lookup(buf, 0, &nd);
- if (err) {
- cache_put(&ek->h, &svc_expkey_cache);
+ if (err)
goto out;
- }

dprintk("Found the path %s\n", buf);
key.ek_path = nd.path;

ek = svc_expkey_update(&key, ek);
- if (ek)
- cache_put(&ek->h, &svc_expkey_cache);
- else
+ if (!ek)
err = -ENOMEM;
path_put(&nd.path);
}
cache_flush();
out:
+ if (ek)
+ cache_put(&ek->h, &svc_expkey_cache);
if (dom)
auth_domain_put(dom);
kfree(buf);