diff options
| author | Reshetova, Elena <elena.reshetova@intel.com> | 2017-07-04 09:35:02 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-07-04 01:29:04 -0700 |
| commit | 0029c0deb590bc18732327d53b8fdab12eec6d7c (patch) | |
| tree | f7c443301baeff0f7e2fcf848bfb8f6545e74146 | |
| parent | f6a6fede28e3cc3f9e4669a12839b47011330d95 (diff) | |
net, ipv4: convert fib_info.fib_clntref 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/ip_fib.h | 7 | ||||
| -rw-r--r-- | net/ipv4/fib_semantics.c | 2 | ||||
| -rw-r--r-- | net/ipv4/fib_trie.c | 2 |
3 files changed, 6 insertions, 5 deletions
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 3dbfd5e6a347..41d580c6185f 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -23,6 +23,7 @@ #include <net/inetpeer.h> #include <linux/percpu.h> #include <linux/notifier.h> +#include <linux/refcount.h> struct fib_config { u8 fc_dst_len; @@ -105,7 +106,7 @@ struct fib_info { struct hlist_node fib_lhash; struct net *fib_net; int fib_treeref; - atomic_t fib_clntref; + refcount_t fib_clntref; unsigned int fib_flags; unsigned char fib_dead; unsigned char fib_protocol; @@ -430,12 +431,12 @@ void free_fib_info(struct fib_info *fi); static inline void fib_info_hold(struct fib_info *fi) { - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); } static inline void fib_info_put(struct fib_info *fi) { - if (atomic_dec_and_test(&fi->fib_clntref)) + if (refcount_dec_and_test(&fi->fib_clntref)) free_fib_info(fi); } diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index ff47ea1408fe..222100103808 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -1253,7 +1253,7 @@ link_it: } fi->fib_treeref++; - atomic_inc(&fi->fib_clntref); + refcount_set(&fi->fib_clntref, 1); spin_lock_bh(&fib_info_lock); hlist_add_head(&fi->fib_hash, &fib_info_hash[fib_info_hashfn(fi)]); diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index d56659e97a6e..64668c69dda6 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1463,7 +1463,7 @@ found: } if (!(fib_flags & FIB_LOOKUP_NOREF)) - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); res->prefix = htonl(n->key); res->prefixlen = KEYLENGTH - fa->fa_slen; |