From e0542dd5185e68247b08c3418bdba14644b4c414 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:00 +0300 Subject: net, decnet: convert dn_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 Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller --- include/net/dn_fib.h | 5 +++-- net/decnet/dn_fib.c | 6 +++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/include/net/dn_fib.h b/include/net/dn_fib.h index f2ca135ddcc9..81210a8b8d7c 100644 --- a/include/net/dn_fib.h +++ b/include/net/dn_fib.h @@ -2,6 +2,7 @@ #define _NET_DN_FIB_H #include +#include extern const struct nla_policy rtm_dn_policy[]; @@ -28,7 +29,7 @@ struct dn_fib_info { struct dn_fib_info *fib_next; struct dn_fib_info *fib_prev; int fib_treeref; - atomic_t fib_clntref; + refcount_t fib_clntref; int fib_dead; unsigned int fib_flags; int fib_protocol; @@ -130,7 +131,7 @@ void dn_fib_free_info(struct dn_fib_info *fi); static inline void dn_fib_info_put(struct dn_fib_info *fi) { - if (atomic_dec_and_test(&fi->fib_clntref)) + if (refcount_dec_and_test(&fi->fib_clntref)) dn_fib_free_info(fi); } diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c index f9058ebeb635..f9f6fb3f3c5b 100644 --- a/net/decnet/dn_fib.c +++ b/net/decnet/dn_fib.c @@ -389,7 +389,7 @@ link_it: } fi->fib_treeref++; - atomic_inc(&fi->fib_clntref); + refcount_set(&fi->fib_clntref, 1); spin_lock(&dn_fib_info_lock); fi->fib_next = dn_fib_info_list; fi->fib_prev = NULL; @@ -425,7 +425,7 @@ int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn switch (type) { case RTN_NAT: DN_FIB_RES_RESET(*res); - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); return 0; case RTN_UNICAST: case RTN_LOCAL: @@ -438,7 +438,7 @@ int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn } if (nhsel < fi->fib_nhs) { res->nh_sel = nhsel; - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); return 0; } endfor_nexthops(fi); -- cgit