From 22626216c46f2ec86287e75ea86dd9ac3df54265 Mon Sep 17 00:00:00 2001 From: Chidambar 'ilLogict' Zinnoury Date: Tue, 11 Mar 2008 18:05:02 -0700 Subject: [PATCH] [SCTP]: Fix local_addr deletions during list traversals. Since the lists are circular, we need to explicitely tag the address to be deleted since we might end up freeing the list head instead. This fixes some interesting SCTP crashes. Signed-off-by: Chidambar 'ilLogict' Zinnoury Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/bind_addr.c | 4 +++- net/sctp/ipv6.c | 4 +++- net/sctp/protocol.c | 4 +++- 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c index a27511e..ceefda0 100644 --- a/net/sctp/bind_addr.c +++ b/net/sctp/bind_addr.c @@ -209,6 +209,7 @@ int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new, int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr) { struct sctp_sockaddr_entry *addr, *temp; + int found = 0; /* We hold the socket lock when calling this function, * and that acts as a writer synchronizing lock. @@ -216,13 +217,14 @@ int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr) list_for_each_entry_safe(addr, temp, &bp->address_list, list) { if (sctp_cmp_addr_exact(&addr->a, del_addr)) { /* Found the exact match. */ + found = 1; addr->valid = 0; list_del_rcu(&addr->list); break; } } - if (addr && !addr->valid) { + if (found) { call_rcu(&addr->rcu, sctp_local_addr_free); SCTP_DBG_OBJCNT_DEC(addr); return 0; diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index 87f9405..9aa0733 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -89,6 +89,7 @@ static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev, struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; struct sctp_sockaddr_entry *addr = NULL; struct sctp_sockaddr_entry *temp; + int found = 0; switch (ev) { case NETDEV_UP: @@ -111,13 +112,14 @@ static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev, &sctp_local_addr_list, list) { if (ipv6_addr_equal(&addr->a.v6.sin6_addr, &ifa->addr)) { + found = 1; addr->valid = 0; list_del_rcu(&addr->list); break; } } spin_unlock_bh(&sctp_local_addr_lock); - if (addr && !addr->valid) + if (found) call_rcu(&addr->rcu, sctp_local_addr_free); break; } diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 688546d..ad0a406 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -628,6 +628,7 @@ static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev, struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; struct sctp_sockaddr_entry *addr = NULL; struct sctp_sockaddr_entry *temp; + int found = 0; switch (ev) { case NETDEV_UP: @@ -647,13 +648,14 @@ static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev, list_for_each_entry_safe(addr, temp, &sctp_local_addr_list, list) { if (addr->a.v4.sin_addr.s_addr == ifa->ifa_local) { + found = 1; addr->valid = 0; list_del_rcu(&addr->list); break; } } spin_unlock_bh(&sctp_local_addr_lock); - if (addr && !addr->valid) + if (found) call_rcu(&addr->rcu, sctp_local_addr_free); break; } -- 2.7.4