On Mon, 17 Jan 2011, Mi Jinlong wrote:
>
>
> Jesper Juhl:
> > strrchr() can return NULL if nothing is found. If this happens we'll
> > dereference a NULL pointer in
> > fs/nfs/nfs4filelayoutdev.c::decode_and_add_ds().
> >
> > I tried to find some other code that guarantees that this can never
> > happen but I was unsuccessful. So, unless someone else can point to some
> > code that ensures this can never be a problem, I believe this patch is
> > needed.
> >
> > While I was changing this code I also noticed that all the dprintk()
> > statements, except one, start with "%s:". The one missing the ":" I added
> > it to.
>
> Maybe another one also should be changed at decode_and_add_ds() at line 243:
>
> 243 printk("%s Decoded address and port %s\n", __func__, buf);
>
Missed that one. Thanks.
Signed-off-by: Jesper Juhl <jj@xxxxxxxxxxxxx>
---
nfs4filelayoutdev.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index 51fe64a..f5c9b12 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -214,7 +214,7 @@ decode_and_add_ds(__be32 **pp, struct inode *inode)
/* ipv6 length plus port is legal */
if (rlen > INET6_ADDRSTRLEN + 8) {
- dprintk("%s Invalid address, length %d\n", __func__,
+ dprintk("%s: Invalid address, length %d\n", __func__,
rlen);
goto out_err;
}
@@ -225,6 +225,11 @@ decode_and_add_ds(__be32 **pp, struct inode *inode)
/* replace the port dots with dashes for the in4_pton() delimiter*/
for (i = 0; i < 2; i++) {
char *res = strrchr(buf, '.');
+ if (!res) {
+ dprintk("%s: Failed finding expected dots in port\n",
+ __func__);
+ goto out_free;
+ }
*res = '-';
}
@@ -240,7 +245,7 @@ decode_and_add_ds(__be32 **pp, struct inode *inode)
port = htons((tmp[0] << 8) | (tmp[1]));
ds = nfs4_pnfs_ds_add(inode, ip_addr, port);
- dprintk("%s Decoded address and port %s\n", __func__, buf);
+ dprintk("%s: Decoded address and port %s\n", __func__, buf);
out_free:
kfree(buf);
out_err:
--
Jesper Juhl <jj@xxxxxxxxxxxxx> http://www.chaosbits.net/
Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please.
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