lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 21 Dec 2010 08:38:23 +0900 From: Minchan Kim <minchan.kim@...il.com> To: Jesper Juhl <jj@...osbits.net> Cc: linux-mm@...ck.org, linux-kernel@...r.kernel.org, Andrew Morton <akpm@...ux-foundation.org> Subject: Re: [updated PATCH] Close mem leak in error path in mm/hugetlb.c::nr_hugepages_store_common() On Tue, Dec 21, 2010 at 7:05 AM, Jesper Juhl <jj@...osbits.net> wrote: > On Mon, 20 Dec 2010, Minchan Kim wrote: > >> On Mon, Dec 20, 2010 at 7:10 AM, Jesper Juhl <jj@...osbits.net> wrote: >> > Hi, >> > >> > The NODEMASK_ALLOC macro dynamically allocates memory for its second >> > argument ('nodes_allowed' in this context). >> > In nr_hugepages_store_common() we may abort early if strict_strtoul() >> > fails, but in that case we do not free the memory already allocated to >> > 'nodes_allowed', causing a memory leak. >> > This patch closes the leak by freeing the memory in the error path. >> > >> > >> > Signed-off-by: Jesper Juhl <jj@...osbits.net> >> > --- >> > hugetlb.c | 4 +++- >> > 1 file changed, 3 insertions(+), 1 deletion(-) >> > >> > compile tested only >> > >> > diff --git a/mm/hugetlb.c b/mm/hugetlb.c >> > index 8585524..9fdcc35 100644 >> > --- a/mm/hugetlb.c >> > +++ b/mm/hugetlb.c >> > @@ -1439,8 +1439,10 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy, >> > NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY); >> > >> > err = strict_strtoul(buf, 10, &count); >> > - if (err) >> > + if (err) { >> > + kfree(nodes_allowed); >> >> Nice catch. But use NODEMASK_FREE. It might be not kmalloced object. >> > Right. I just checked the macro and it used kmalloc(), so I just wrote > kfree. But you are right, NODEMASK_FREE is the right thing to use here. > Updated patch below. > > > Signed-off-by: Jesper Juhl <jj@...osbits.net> Reviewed-by: Minchan Kim <minchan.kim@...il.com> Could you resend the completed patch to save Andrew trouble? -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists