diff options
| author | Reshetova, Elena <elena.reshetova@intel.com> | 2017-07-04 09:34:54 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-07-04 01:29:03 -0700 |
| commit | 0aeea21ada517b99a6e95298ffc105381bcd3a52 (patch) | |
| tree | 5a09b35a770e6893d3f146053463a64ddce6488b | |
| parent | 25f4535a94c2b38d09912d7e8bab371c9e97be38 (diff) | |
net, ipv6: convert ipv6_txoptions.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/ipv6.h | 7 | ||||
| -rw-r--r-- | net/ipv6/exthdrs.c | 4 | ||||
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 2 |
3 files changed, 7 insertions, 6 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 3e505bbff8ca..6eac5cf8f1e6 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -16,6 +16,7 @@ #include <linux/ipv6.h> #include <linux/hardirq.h> #include <linux/jhash.h> +#include <linux/refcount.h> #include <net/if_inet6.h> #include <net/ndisc.h> #include <net/flow.h> @@ -203,7 +204,7 @@ extern rwlock_t ip6_ra_lock; */ struct ipv6_txoptions { - atomic_t refcnt; + refcount_t refcnt; /* Length of this structure */ int tot_len; @@ -265,7 +266,7 @@ static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np) rcu_read_lock(); opt = rcu_dereference(np->opt); if (opt) { - if (!atomic_inc_not_zero(&opt->refcnt)) + if (!refcount_inc_not_zero(&opt->refcnt)) opt = NULL; else opt = rcu_pointer_handoff(opt); @@ -276,7 +277,7 @@ static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np) static inline void txopt_put(struct ipv6_txoptions *opt) { - if (opt && atomic_dec_and_test(&opt->refcnt)) + if (opt && refcount_dec_and_test(&opt->refcnt)) kfree_rcu(opt, rcu); } diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index 0460af226011..4996d734f1d2 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -971,7 +971,7 @@ ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) *((char **)&opt2->dst1opt) += dif; if (opt2->srcrt) *((char **)&opt2->srcrt) += dif; - atomic_set(&opt2->refcnt, 1); + refcount_set(&opt2->refcnt, 1); } return opt2; } @@ -1056,7 +1056,7 @@ ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, return ERR_PTR(-ENOBUFS); memset(opt2, 0, tot_len); - atomic_set(&opt2->refcnt, 1); + refcount_set(&opt2->refcnt, 1); opt2->tot_len = tot_len; p = (char *)(opt2 + 1); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index a531ba032b85..85404e7c3114 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -505,7 +505,7 @@ sticky_done: break; memset(opt, 0, sizeof(*opt)); - atomic_set(&opt->refcnt, 1); + refcount_set(&opt->refcnt, 1); opt->tot_len = sizeof(*opt) + optlen; retv = -EFAULT; if (copy_from_user(opt+1, optval, optlen)) |