From 905db44087855e3c1709f538ecdc22fd149cadd8 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 30 Jan 2009 14:12:06 -0800 Subject: packet: Avoid lock_sock in mmap handler MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As the mmap handler gets called under mmap_sem, and we may grab mmap_sem elsewhere under the socket lock to access user data, we should avoid grabbing the socket lock in the mmap handler. Since the only thing we care about in the mmap handler is for pg_vec* to be invariant, i.e., to exclude packet_set_ring, we can achieve this by simply using a new mutex. Signed-off-by: Herbert Xu Tested-by: Martin MOKREJŠ Signed-off-by: David S. Miller --- net/packet/af_packet.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 5f94db2f3e9..9454d4ae46d 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -77,6 +77,7 @@ #include #include #include +#include #ifdef CONFIG_INET #include @@ -175,6 +176,7 @@ struct packet_sock { #endif struct packet_type prot_hook; spinlock_t bind_lock; + struct mutex pg_vec_lock; unsigned int running:1, /* prot_hook is attached*/ auxdata:1, origdev:1; @@ -1069,6 +1071,7 @@ static int packet_create(struct net *net, struct socket *sock, int protocol) */ spin_lock_init(&po->bind_lock); + mutex_init(&po->pg_vec_lock); po->prot_hook.func = packet_rcv; if (sock->type == SOCK_PACKET) @@ -1865,6 +1868,7 @@ static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing synchronize_net(); err = -EBUSY; + mutex_lock(&po->pg_vec_lock); if (closing || atomic_read(&po->mapped) == 0) { err = 0; #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; }) @@ -1886,6 +1890,7 @@ static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing if (atomic_read(&po->mapped)) printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped)); } + mutex_unlock(&po->pg_vec_lock); spin_lock(&po->bind_lock); if (was_running && !po->running) { @@ -1918,7 +1923,7 @@ static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_st size = vma->vm_end - vma->vm_start; - lock_sock(sk); + mutex_lock(&po->pg_vec_lock); if (po->pg_vec == NULL) goto out; if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE) @@ -1941,7 +1946,7 @@ static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_st err = 0; out: - release_sock(sk); + mutex_unlock(&po->pg_vec_lock); return err; } #endif -- cgit v1.2.3 From 5d6e430d3bafe743b18dc443189093bf532e91ed Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Sat, 31 Jan 2009 00:51:49 -0800 Subject: ipv6: compile fix for ip6mr.c net/ipv6/ip6mr.c: In function 'pim6_rcv': net/ipv6/ip6mr.c:368: error: implicit declaration of function 'csum_ipv6_magic' Signed-off-by: Dave Jones Signed-off-by: David S. Miller --- net/ipv6/ip6mr.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index d19a84b7950..228be551e9c 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -48,6 +48,7 @@ #include #include #include +#include /* Big lock, protecting vif table, mrt cache and mroute socket state. Note that the changes are semaphored via rtnl_lock. -- cgit v1.2.3