From 01db403cf99f739f86903314a489fb420e0e254f Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 27 Sep 2010 20:24:54 -0700 Subject: tcp: Fix >4GB writes on 64-bit. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fixes kernel bugzilla #16603 tcp_sendmsg() truncates iov_len to an 'int' which a 4GB write to write zero bytes, for example. There is also the problem higher up of how verify_iovec() works. It wants to prevent the total length from looking like an error return value. However it does this using 'int', but syscalls return 'long' (and thus signed 64-bit on 64-bit machines). So it could trigger false-positives on 64-bit as written. So fix it to use 'long'. Reported-by: Olaf Bonorden Reported-by: Daniel Büse Reported-by: Andrew Morton Signed-off-by: David S. Miller --- include/linux/socket.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/socket.h') diff --git a/include/linux/socket.h b/include/linux/socket.h index a2fada9becb6..a8f56e1ec760 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -322,7 +322,7 @@ extern int csum_partial_copy_fromiovecend(unsigned char *kdata, int offset, unsigned int len, __wsum *csump); -extern int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode); +extern long verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode); extern int memcpy_toiovec(struct iovec *v, unsigned char *kdata, int len); extern int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata, int offset, int len); -- cgit From 11165f1457181e4499e5eada442434a07827ffd8 Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Mon, 18 Oct 2010 14:27:29 +0000 Subject: socket: localize functions A couple of functions in socket.c are only used there and should be localized. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/linux/socket.h | 1 - net/socket.c | 7 ++++--- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'include/linux/socket.h') diff --git a/include/linux/socket.h b/include/linux/socket.h index a8f56e1ec760..5146b50202ce 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -326,7 +326,6 @@ extern long verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *a extern int memcpy_toiovec(struct iovec *v, unsigned char *kdata, int len); extern int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata, int offset, int len); -extern int move_addr_to_user(struct sockaddr *kaddr, int klen, void __user *uaddr, int __user *ulen); extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr *kaddr); extern int put_cmsg(struct msghdr*, int level, int type, int len, void *data); diff --git a/net/socket.c b/net/socket.c index 717a5f1c8792..72da57d6ab7b 100644 --- a/net/socket.c +++ b/net/socket.c @@ -209,8 +209,8 @@ int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr *kaddr) * specified. Zero is returned for a success. */ -int move_addr_to_user(struct sockaddr *kaddr, int klen, void __user *uaddr, - int __user *ulen) +static int move_addr_to_user(struct sockaddr *kaddr, int klen, + void __user *uaddr, int __user *ulen) { int err; int len; @@ -661,7 +661,8 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, } EXPORT_SYMBOL_GPL(__sock_recv_timestamp); -inline void sock_recv_drops(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) +static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk, + struct sk_buff *skb) { if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && skb->dropcount) put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL, -- cgit From 8acfe468b0384e834a303f08ebc4953d72fb690a Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 28 Oct 2010 11:41:55 -0700 Subject: net: Limit socket I/O iovec total length to INT_MAX. This helps protect us from overflow issues down in the individual protocol sendmsg/recvmsg handlers. Once we hit INT_MAX we truncate out the rest of the iovec by setting the iov_len members to zero. This works because: 1) For SOCK_STREAM and SOCK_SEQPACKET sockets, partial writes are allowed and the application will just continue with another write to send the rest of the data. 2) For datagram oriented sockets, where there must be a one-to-one correspondance between write() calls and packets on the wire, INT_MAX is going to be far larger than the packet size limit the protocol is going to check for and signal with -EMSGSIZE. Based upon a patch by Linus Torvalds. Signed-off-by: David S. Miller --- include/linux/socket.h | 2 +- net/compat.c | 10 ++++++---- net/core/iovec.c | 20 +++++++++----------- 3 files changed, 16 insertions(+), 16 deletions(-) (limited to 'include/linux/socket.h') diff --git a/include/linux/socket.h b/include/linux/socket.h index 5146b50202ce..86b652fabf6e 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -322,7 +322,7 @@ extern int csum_partial_copy_fromiovecend(unsigned char *kdata, int offset, unsigned int len, __wsum *csump); -extern long verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode); +extern int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode); extern int memcpy_toiovec(struct iovec *v, unsigned char *kdata, int len); extern int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata, int offset, int len); diff --git a/net/compat.c b/net/compat.c index 63d260e81472..3649d5895361 100644 --- a/net/compat.c +++ b/net/compat.c @@ -41,10 +41,12 @@ static inline int iov_from_user_compat_to_kern(struct iovec *kiov, compat_size_t len; if (get_user(len, &uiov32->iov_len) || - get_user(buf, &uiov32->iov_base)) { - tot_len = -EFAULT; - break; - } + get_user(buf, &uiov32->iov_base)) + return -EFAULT; + + if (len > INT_MAX - tot_len) + len = INT_MAX - tot_len; + tot_len += len; kiov->iov_base = compat_ptr(buf); kiov->iov_len = (__kernel_size_t) len; diff --git a/net/core/iovec.c b/net/core/iovec.c index 72aceb1fe4fa..c40f27e7d208 100644 --- a/net/core/iovec.c +++ b/net/core/iovec.c @@ -35,10 +35,9 @@ * in any case. */ -long verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode) +int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode) { - int size, ct; - long err; + int size, ct, err; if (m->msg_namelen) { if (mode == VERIFY_READ) { @@ -62,14 +61,13 @@ long verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, err = 0; for (ct = 0; ct < m->msg_iovlen; ct++) { - err += iov[ct].iov_len; - /* - * Goal is not to verify user data, but to prevent returning - * negative value, which is interpreted as errno. - * Overflow is still possible, but it is harmless. - */ - if (err < 0) - return -EMSGSIZE; + size_t len = iov[ct].iov_len; + + if (len > INT_MAX - err) { + len = INT_MAX - err; + iov[ct].iov_len = len; + } + err += len; } return err; -- cgit