On Wed, 11 Jan 2012 10:46:27 +0300 Dan Carpenter <[email protected]> wrote:
> On 32 bit systems num_aces * sizeof(struct cifs_ace *) could overflow > leading to a smaller ppace buffer than we expected. > > Signed-off-by: Dan Carpenter <[email protected]> > > diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c > index 72ddf23..c1b2544 100644 > --- a/fs/cifs/cifsacl.c > +++ b/fs/cifs/cifsacl.c > @@ -909,6 +909,8 @@ static void parse_dacl(struct cifs_acl *pdacl, char > *end_of_acl, > umode_t group_mask = S_IRWXG; > umode_t other_mask = S_IRWXU | S_IRWXG | S_IRWXO; > > + if (num_aces > ULONG_MAX / sizeof(struct cifs_ace *)) > + return; > ppace = kmalloc(num_aces * sizeof(struct cifs_ace *), > GFP_KERNEL); > if (!ppace) { Looks plausible. This function could use some work. I'm not sure why num_aces is signed here too... The first arg to kmalloc is a size_t. Does that boil down to an unsigned long on all arches? -- Jeff Layton <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
