net, ipv4: convert cipso_v4_doi.refcount 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>
This commit is contained in:
Reshetova, Elena 2017-07-04 09:35:01 +03:00 committed by David S. Miller
parent 87078f26b6
commit f6a6fede28
2 changed files with 8 additions and 7 deletions

View File

@ -41,6 +41,7 @@
#include <net/netlabel.h>
#include <net/request_sock.h>
#include <linux/atomic.h>
#include <linux/refcount.h>
#include <asm/unaligned.h>
/* known doi values */
@ -85,7 +86,7 @@ struct cipso_v4_doi {
} map;
u8 tags[CIPSO_V4_TAG_MAXCNT];
atomic_t refcount;
refcount_t refcount;
struct list_head list;
struct rcu_head rcu;
};

View File

@ -375,7 +375,7 @@ static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
struct cipso_v4_doi *iter;
list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
if (iter->doi == doi && atomic_read(&iter->refcount))
if (iter->doi == doi && refcount_read(&iter->refcount))
return iter;
return NULL;
}
@ -429,7 +429,7 @@ int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
}
}
atomic_set(&doi_def->refcount, 1);
refcount_set(&doi_def->refcount, 1);
spin_lock(&cipso_v4_doi_list_lock);
if (cipso_v4_doi_search(doi_def->doi)) {
@ -533,7 +533,7 @@ int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
ret_val = -ENOENT;
goto doi_remove_return;
}
if (!atomic_dec_and_test(&doi_def->refcount)) {
if (!refcount_dec_and_test(&doi_def->refcount)) {
spin_unlock(&cipso_v4_doi_list_lock);
ret_val = -EBUSY;
goto doi_remove_return;
@ -576,7 +576,7 @@ struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
doi_def = cipso_v4_doi_search(doi);
if (!doi_def)
goto doi_getdef_return;
if (!atomic_inc_not_zero(&doi_def->refcount))
if (!refcount_inc_not_zero(&doi_def->refcount))
doi_def = NULL;
doi_getdef_return:
@ -597,7 +597,7 @@ void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
if (!doi_def)
return;
if (!atomic_dec_and_test(&doi_def->refcount))
if (!refcount_dec_and_test(&doi_def->refcount))
return;
spin_lock(&cipso_v4_doi_list_lock);
list_del_rcu(&doi_def->list);
@ -630,7 +630,7 @@ int cipso_v4_doi_walk(u32 *skip_cnt,
rcu_read_lock();
list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
if (atomic_read(&iter_doi->refcount) > 0) {
if (refcount_read(&iter_doi->refcount) > 0) {
if (doi_cnt++ < *skip_cnt)
continue;
ret_val = callback(iter_doi, cb_arg);