From f398035f2dec0a6150833b0bc105057953594edb Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 19 Dec 2007 23:44:29 -0800 Subject: [IPSEC]: Avoid undefined shift operation when testing algorithm ID The aalgos/ealgos fields are only 32 bits wide. However, af_key tries to test them with the expression 1 << id where id can be as large as 253. This produces different behaviour on different architectures. The following patch explicitly checks whether ID is greater than 31 and fails the check if that's the case. We cannot easily extend the mask to be longer than 32 bits due to exposure to user-space. Besides, this whole interface is obsolete anyway in favour of the xfrm_user interface which doesn't use this bit mask in templates (well not within the kernel anyway). Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/key/af_key.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'net/key') diff --git a/net/key/af_key.c b/net/key/af_key.c index 878039b9557d..26d5e63c4cc5 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -2784,12 +2784,22 @@ static struct sadb_msg *pfkey_get_base_msg(struct sk_buff *skb, int *errp) static inline int aalg_tmpl_set(struct xfrm_tmpl *t, struct xfrm_algo_desc *d) { - return t->aalgos & (1 << d->desc.sadb_alg_id); + unsigned int id = d->desc.sadb_alg_id; + + if (id >= sizeof(t->aalgos) * 8) + return 0; + + return (t->aalgos >> id) & 1; } static inline int ealg_tmpl_set(struct xfrm_tmpl *t, struct xfrm_algo_desc *d) { - return t->ealgos & (1 << d->desc.sadb_alg_id); + unsigned int id = d->desc.sadb_alg_id; + + if (id >= sizeof(t->ealgos) * 8) + return 0; + + return (t->ealgos >> id) & 1; } static int count_ah_combs(struct xfrm_tmpl *t) -- cgit v1.2.3-58-ga151