Commit c25b7a7a authored by Florian Westphal's avatar Florian Westphal Committed by Paolo Abeni
Browse files

inet: ping: use hlist_nulls rcu iterator during lookup 



ping_lookup() does not acquire the table spinlock, so iteration should
use hlist_nulls_for_each_entry_rcu().

Spotted during code review.

Fixes: dbca1596 ("ping: convert to RCU lookups, get rid of rwlock")
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20221129140644.28525-1-fw@strlen.de


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 9aff0ec5

.clang-format

+1 −0
Original line number Original line Diff line number Diff line
@@ -535,6 +535,7 @@ ForEachMacros: 
  - 'perf_hpp_list__for_each_sort_list_safe'

  - 'perf_hpp_list__for_each_sort_list_safe'

  - 'perf_pmu__for_each_hybrid_pmu'

  - 'perf_pmu__for_each_hybrid_pmu'

  - 'ping_portaddr_for_each_entry'

  - 'ping_portaddr_for_each_entry'

  - 'ping_portaddr_for_each_entry_rcu'

  - 'plist_for_each'

  - 'plist_for_each'

  - 'plist_for_each_continue'

  - 'plist_for_each_continue'

  - 'plist_for_each_entry'

  - 'plist_for_each_entry'

include/net/ping.h

+0 −3
Original line number Original line Diff line number Diff line
@@ -16,9 +16,6 @@ 
#define PING_HTABLE_SIZE 	64

#define PING_HTABLE_SIZE 	64

#define PING_HTABLE_MASK 	(PING_HTABLE_SIZE-1)

#define PING_HTABLE_MASK 	(PING_HTABLE_SIZE-1)





#define ping_portaddr_for_each_entry(__sk, node, list) \

	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)



/*

/*

 * gid_t is either uint or ushort.  We want to pass it to

 * gid_t is either uint or ushort.  We want to pass it to

 * proc_dointvec_minmax(), so it must not be larger than MAX_INT

 * proc_dointvec_minmax(), so it must not be larger than MAX_INT

net/ipv4/ping.c

+6 −1
Original line number Original line Diff line number Diff line
@@ -49,6 +49,11 @@ 
#include <net/transp_v6.h>

#include <net/transp_v6.h>

#endif

#endif





#define ping_portaddr_for_each_entry(__sk, node, list) \

	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)

#define ping_portaddr_for_each_entry_rcu(__sk, node, list) \

	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)



struct ping_table {

struct ping_table {

	struct hlist_nulls_head	hash[PING_HTABLE_SIZE];

	struct hlist_nulls_head	hash[PING_HTABLE_SIZE];

	spinlock_t		lock;

	spinlock_t		lock;
@@ -192,7 +197,7 @@ static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident) 
		return NULL;

		return NULL;

	}

	}





	ping_portaddr_for_each_entry(sk, hnode, hslot) {

	ping_portaddr_for_each_entry_rcu(sk, hnode, hslot) {

		isk = inet_sk(sk);

		isk = inet_sk(sk);





		pr_debug("iterate\n");

		pr_debug("iterate\n");