From f6a6fede28e3cc3f9e4669a12839b47011330d95 Mon Sep 17 00:00:00 2001
From: "Reshetova, Elena" <elena.reshetova@intel.com>
Date: Tue, 4 Jul 2017 09:35:01 +0300
Subject: [PATCH] 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>
---
include/net/cipso_ipv4.h | 3 ++-
net/ipv4/cipso_ipv4.c | 12 ++++++------
2 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/include/net/cipso_ipv4.h b/include/net/cipso_ipv4.h
index a34b141f125f0..880adb2f2afdc 100644
--- a/include/net/cipso_ipv4.h
+++ b/include/net/cipso_ipv4.h
@@ -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;
};
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index c2044775ae7da..c4c6e1969ed06 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -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);