[SCM] Samba Shared Repository - branch v3-5-stable updated

Karolin Seeger kseeger at samba.org
Mon Feb 28 06:11:48 MST 2011


The branch, v3-5-stable has been updated
       via  ba3837e WHATSNEW: Prepare 3.5.7 release notes.
       via  c3ad6eb Fix denial of service - memory corruption.
      from  01a15b1 WHATASNEW: Start 3.5.7 release notes.

http://gitweb.samba.org/?p=samba.git;a=shortlog;h=v3-5-stable


- Log -----------------------------------------------------------------
commit ba3837e1ce6024e8cc5153e803d32a6ed750408b
Author: Karolin Seeger <kseeger at samba.org>
Date:   Sun Feb 27 18:42:19 2011 +0100

    WHATSNEW: Prepare 3.5.7 release notes.
    
    Karolin

commit c3ad6eb506623435d3d9ce62d6f34ed1c960d4be
Author: Jeremy Allison <jra at samba.org>
Date:   Sun Feb 27 17:58:06 2011 +0100

    Fix denial of service - memory corruption.
    
    CVE-2011-0719
    
    Fix bug #7949 (DoS in Winbind and smbd with many file descriptors open).
    
    All current released versions of Samba are vulnerable to
    a denial of service caused by memory corruption. Range
    checks on file descriptors being used in the FD_SET macro
    were not present allowing stack corruption. This can cause
    the Samba code to crash or to loop attempting to select
    on a bad file descriptor set.
    
    A connection to a file share, or a local account is needed
    to exploit this problem, either authenticated or unauthenticated
    (guest connection).
    
    Currently we do not believe this flaw is exploitable
    beyond a crash or causing the code to loop, but on the
    advice of our security reviewers we are releasing fixes
    in case an exploit is discovered at a later date.

-----------------------------------------------------------------------

Summary of changes:
 WHATSNEW.txt                     |   19 +++++++++++++------
 lib/tevent/tevent_select.c       |   10 ++++++++++
 lib/tevent/tevent_standard.c     |    5 +++++
 nsswitch/libwbclient/wbc_async.c |    2 +-
 nsswitch/wb_common.c             |   14 ++++++++++++++
 source3/client/client.c          |    4 +++-
 source3/client/dnsbrowse.c       |   11 +++++++++++
 source3/lib/events.c             |    8 ++++++++
 source3/lib/g_lock.c             |    4 +++-
 source3/lib/packet.c             |    5 +++++
 source3/lib/readline.c           |    5 +++++
 source3/lib/select.c             |   12 ++++++++++++
 source3/lib/util_sock.c          |   15 ++++++++++++---
 source3/libaddns/dnssock.c       |    5 +++++
 source3/libsmb/nmblib.c          |    5 +++++
 source3/nmbd/nmbd_packets.c      |   37 +++++++++++++++++++++++++++++++------
 source3/utils/smbfilter.c        |    7 +++++--
 source3/winbindd/winbindd_dual.c |    7 +++++++
 18 files changed, 155 insertions(+), 20 deletions(-)


Changeset truncated at 500 lines:

diff --git a/WHATSNEW.txt b/WHATSNEW.txt
index a9edeb1..6d6a61c 100644
--- a/WHATSNEW.txt
+++ b/WHATSNEW.txt
@@ -1,20 +1,27 @@
                    =============================
                    Release Notes for Samba 3.5.7
-			  , 2010
+			  February 28, 2011
                    =============================
 
 
-This is the latest stable release of Samba 3.5.
+This is a security release in order to address CVE-2011-0719.
 
-Major enhancements in Samba 3.5.7 include:
 
-  o
+o  CVE-2011-0719:
+   All current released versions of Samba are vulnerable to
+   a denial of service caused by memory corruption. Range
+   checks on file descriptors being used in the FD_SET macro
+   were not present allowing stack corruption. This can cause
+   the Samba code to crash or to loop attempting to select
+   on a bad file descriptor set.
 
-Changes since 3.5.5
--------------------
+
+Changes since 3.5.6:
+--------------------
 
 
 o   Jeremy Allison <jra at samba.org>
+    * BUG 7949: Fix DoS in Winbind and smbd with many file descriptors open.
 
 
 ######################################################################
diff --git a/lib/tevent/tevent_select.c b/lib/tevent/tevent_select.c
index d974189..890e031 100644
--- a/lib/tevent/tevent_select.c
+++ b/lib/tevent/tevent_select.c
@@ -111,6 +111,11 @@ static struct tevent_fd *select_event_add_fd(struct tevent_context *ev, TALLOC_C
 							   struct select_event_context);
 	struct tevent_fd *fde;
 
+	if (fd < 0 || fd >= FD_SETSIZE) {
+		errno = EBADF;
+		return NULL;
+	}
+
 	fde = tevent_common_add_fd(ev, mem_ctx, fd, flags,
 				   handler, private_data,
 				   handler_name, location);
@@ -143,6 +148,11 @@ static int select_event_loop_select(struct select_event_context *select_ev, stru
 
 	/* setup any fd events */
 	for (fde = select_ev->ev->fd_events; fde; fde = fde->next) {
+		if (fde->fd < 0 || fde->fd >= FD_SETSIZE) {
+			errno = EBADF;
+			return -1;
+		}
+
 		if (fde->flags & TEVENT_FD_READ) {
 			FD_SET(fde->fd, &r_fds);
 		}
diff --git a/lib/tevent/tevent_standard.c b/lib/tevent/tevent_standard.c
index c3f8b36..d4a00cc 100644
--- a/lib/tevent/tevent_standard.c
+++ b/lib/tevent/tevent_standard.c
@@ -457,6 +457,11 @@ static int std_event_loop_select(struct std_event_context *std_ev, struct timeva
 
 	/* setup any fd events */
 	for (fde = std_ev->ev->fd_events; fde; fde = fde->next) {
+		if (fde->fd < 0 || fde->fd >= FD_SETSIZE) {
+			std_ev->exit_code = EBADF;
+			return -1;
+		}
+
 		if (fde->flags & TEVENT_FD_READ) {
 			FD_SET(fde->fd, &r_fds);
 		}
diff --git a/nsswitch/libwbclient/wbc_async.c b/nsswitch/libwbclient/wbc_async.c
index 181d546..bb95b91 100644
--- a/nsswitch/libwbclient/wbc_async.c
+++ b/nsswitch/libwbclient/wbc_async.c
@@ -509,7 +509,7 @@ static bool closed_fd(int fd)
 	fd_set r_fds;
 	int selret;
 
-	if (fd == -1) {
+	if (fd < 0 || fd >= FD_SETSIZE) {
 		return true;
 	}
 
diff --git a/nsswitch/wb_common.c b/nsswitch/wb_common.c
index b7fafc3..def41d5 100644
--- a/nsswitch/wb_common.c
+++ b/nsswitch/wb_common.c
@@ -244,6 +244,10 @@ static int winbind_named_pipe_sock(const char *dir)
 		switch (errno) {
 			case EINPROGRESS:
 				FD_ZERO(&w_fds);
+				if (fd < 0 || fd >= FD_SETSIZE) {
+					errno = EBADF;
+					goto error_out;
+				}
 				FD_SET(fd, &w_fds);
 				tv.tv_sec = CONNECT_TIMEOUT - wait_time;
 				tv.tv_usec = 0;
@@ -391,6 +395,11 @@ int winbind_write_sock(void *buffer, int count, int recursing, int need_priv)
 		   call would not block by calling select(). */
 
 		FD_ZERO(&r_fds);
+		if (winbindd_fd < 0 || winbindd_fd >= FD_SETSIZE) {
+			errno = EBADF;
+			winbind_close_sock();
+			return -1;
+		}
 		FD_SET(winbindd_fd, &r_fds);
 		ZERO_STRUCT(tv);
 
@@ -451,6 +460,11 @@ int winbind_read_sock(void *buffer, int count)
 		   call would not block by calling select(). */
 
 		FD_ZERO(&r_fds);
+		if (winbindd_fd < 0 || winbindd_fd >= FD_SETSIZE) {
+			errno = EBADF;
+			winbind_close_sock();
+			return -1;
+		}
 		FD_SET(winbindd_fd, &r_fds);
 		ZERO_STRUCT(tv);
 		/* Wait for 5 seconds for a reply. May need to parameterise this... */
diff --git a/source3/client/client.c b/source3/client/client.c
index 6d39977..e1952b5 100644
--- a/source3/client/client.c
+++ b/source3/client/client.c
@@ -4420,8 +4420,10 @@ static void readline_callback(void)
 
  again:
 
-	if (cli->fd == -1)
+	if (cli->fd < 0 || cli->fd >= FD_SETSIZE) {
+		errno = EBADF;
 		return;
+	}
 
 	FD_ZERO(&fds);
 	FD_SET(cli->fd,&fds);
diff --git a/source3/client/dnsbrowse.c b/source3/client/dnsbrowse.c
index 5e3a4de..a6b9360 100644
--- a/source3/client/dnsbrowse.c
+++ b/source3/client/dnsbrowse.c
@@ -81,6 +81,11 @@ static void do_smb_resolve(struct mdns_smbsrv_result *browsesrv)
 			TALLOC_FREE(fdset);
 		}
 
+		if (mdnsfd < 0 || mdnsfd >= FD_SETSIZE) {
+			errno = EBADF;
+			break;
+		}
+
 		fdsetsz = howmany(mdnsfd + 1, NFDBITS) * sizeof(fd_mask);
 		fdset = TALLOC_ZERO(ctx, fdsetsz);
 		FD_SET(mdnsfd, fdset);
@@ -181,6 +186,12 @@ int do_smb_browse(void)
 			TALLOC_FREE(fdset);
 		}
 
+		if (mdnsfd < 0 || mdnsfd >= FD_SETSIZE) {
+			errno = EBADF;
+			TALLOC_FREE(ctx);
+			return 1;
+		}
+
 		fdsetsz = howmany(mdnsfd + 1, NFDBITS) * sizeof(fd_mask);
 		fdset = TALLOC_ZERO(ctx, fdsetsz);
 		FD_SET(mdnsfd, fdset);
diff --git a/source3/lib/events.c b/source3/lib/events.c
index 75aa250..63aba58 100644
--- a/source3/lib/events.c
+++ b/source3/lib/events.c
@@ -55,6 +55,14 @@ bool event_add_to_select_args(struct tevent_context *ev,
 	bool ret = false;
 
 	for (fde = ev->fd_events; fde; fde = fde->next) {
+		if (fde->fd < 0 || fde->fd >= FD_SETSIZE) {
+			/* We ignore here, as it shouldn't be
+			   possible to add an invalid fde->fd
+			   but we don't want FD_SET to see an
+			   invalid fd. */
+			continue;
+		}
+
 		if (fde->flags & EVENT_FD_READ) {
 			FD_SET(fde->fd, read_fds);
 			ret = true;
diff --git a/source3/lib/g_lock.c b/source3/lib/g_lock.c
index 1726047..356c104 100644
--- a/source3/lib/g_lock.c
+++ b/source3/lib/g_lock.c
@@ -391,7 +391,9 @@ NTSTATUS g_lock_lock(struct g_lock_ctx *ctx, const char *name,
 			r_fds = &_r_fds;
 			FD_ZERO(r_fds);
 			max_fd = ctdbd_conn_get_fd(conn);
-			FD_SET(max_fd, r_fds);
+			if (max_fd >= 0 && max_fd < FD_SETSIZE) {
+				FD_SET(max_fd, r_fds);
+			}
 		}
 #endif
 
diff --git a/source3/lib/packet.c b/source3/lib/packet.c
index c131b97..8d815c9 100644
--- a/source3/lib/packet.c
+++ b/source3/lib/packet.c
@@ -107,6 +107,11 @@ NTSTATUS packet_fd_read_sync(struct packet_context *ctx,
 	int res;
 	fd_set r_fds;
 
+	if (ctx->fd < 0 || ctx->fd >= FD_SETSIZE) {
+		errno = EBADF;
+		return map_nt_error_from_unix(errno);
+	}
+
 	FD_ZERO(&r_fds);
 	FD_SET(ctx->fd, &r_fds);
 
diff --git a/source3/lib/readline.c b/source3/lib/readline.c
index 34867aa..70a82f2 100644
--- a/source3/lib/readline.c
+++ b/source3/lib/readline.c
@@ -91,6 +91,11 @@ static char *smb_readline_replacement(const char *prompt, void (*callback)(void)
 		timeout.tv_sec = 5;
 		timeout.tv_usec = 0;
 
+		if (fd < 0 || fd >= FD_SETSIZE) {
+			errno = EBADF;
+			break;
+		}
+
 		FD_ZERO(&fds);
 		FD_SET(fd,&fds);
 
diff --git a/source3/lib/select.c b/source3/lib/select.c
index b5443ff..2230b43 100644
--- a/source3/lib/select.c
+++ b/source3/lib/select.c
@@ -75,6 +75,17 @@ int sys_select(int maxfd, fd_set *readfds, fd_set *writefds, fd_set *errorfds, s
 			return -1;
 		}
 
+		if (select_pipe[0] < 0 || select_pipe[0] >= FD_SETSIZE) {
+			DEBUG(0, ("sys_select: bad fd\n"));
+			if (readfds != NULL)
+				FD_ZERO(readfds);
+			if (writefds != NULL)
+				FD_ZERO(writefds);
+			if (errorfds != NULL)
+				FD_ZERO(errorfds);
+			errno = EBADF;
+			return -1;
+		}
 		/*
 		 * These next two lines seem to fix a bug with the Linux
 		 * 2.0.x kernel (and probably other UNIXes as well) where
@@ -101,6 +112,7 @@ int sys_select(int maxfd, fd_set *readfds, fd_set *writefds, fd_set *errorfds, s
 		readfds2 = &readfds_buf;
 		FD_ZERO(readfds2);
 	}
+
 	FD_SET(select_pipe[0], readfds2);
 
 	errno = 0;
diff --git a/source3/lib/util_sock.c b/source3/lib/util_sock.c
index 08cbced..7a573ad 100644
--- a/source3/lib/util_sock.c
+++ b/source3/lib/util_sock.c
@@ -495,6 +495,11 @@ NTSTATUS read_fd_with_timeout(int fd, char *buf,
 	timeout.tv_usec = (long)(1000 * (time_out % 1000));
 
 	for (nread=0; nread < mincnt; ) {
+		if (fd < 0 || fd >= FD_SETSIZE) {
+			errno = EBADF;
+			return map_nt_error_from_unix(EBADF);
+		}
+
 		FD_ZERO(&fds);
 		FD_SET(fd,&fds);
 
@@ -1235,7 +1240,7 @@ bool open_any_socket_out(struct sockaddr_storage *addrs, int num_addrs,
 
 	for (i=0; i<num_addrs; i++) {
 		sockets[i] = socket(addrs[i].ss_family, SOCK_STREAM, 0);
-		if (sockets[i] < 0)
+		if (sockets[i] < 0 || sockets[i] >= FD_SETSIZE)
 			goto done;
 		set_blocking(sockets[i], false);
 	}
@@ -1284,8 +1289,10 @@ bool open_any_socket_out(struct sockaddr_storage *addrs, int num_addrs,
 	FD_ZERO(&r_fds);
 
 	for (i=0; i<num_addrs; i++) {
-		if (sockets[i] == -1)
+		if (sockets[i] < 0 || sockets[i] >= FD_SETSIZE) {
+			/* This cannot happen - ignore if so. */
 			continue;
+		}
 		FD_SET(sockets[i], &wr_fds);
 		FD_SET(sockets[i], &r_fds);
 		if (sockets[i]>maxfd)
@@ -1305,8 +1312,10 @@ bool open_any_socket_out(struct sockaddr_storage *addrs, int num_addrs,
 
 	for (i=0; i<num_addrs; i++) {
 
-		if (sockets[i] == -1)
+		if (sockets[i] < 0 || sockets[i] >= FD_SETSIZE) {
+			/* This cannot happen - ignore if so. */
 			continue;
+		}
 
 		/* Stevens, Network Programming says that if there's a
 		 * successful connect, the socket is only writable. Upon an
diff --git a/source3/libaddns/dnssock.c b/source3/libaddns/dnssock.c
index 7c8bd41..bf11fea 100644
--- a/source3/libaddns/dnssock.c
+++ b/source3/libaddns/dnssock.c
@@ -219,6 +219,11 @@ static DNS_ERROR read_all(int fd, uint8 *data, size_t len)
 		ssize_t ret;
 		int fd_ready;
 		
+		if (fd < 0 || fd >= FD_SETSIZE) {
+			/* read timeout */
+			return ERROR_DNS_SOCKET_ERROR;
+		}
+
 		FD_ZERO( &rfds );
 		FD_SET( fd, &rfds );
 
diff --git a/source3/libsmb/nmblib.c b/source3/libsmb/nmblib.c
index cf7023a..c82d4dd 100644
--- a/source3/libsmb/nmblib.c
+++ b/source3/libsmb/nmblib.c
@@ -1094,6 +1094,11 @@ struct packet_struct *receive_packet(int fd,enum packet_type type,int t)
 	struct timeval timeout;
 	int ret;
 
+	if (fd < 0 || fd >= FD_SETSIZE) {
+		errno = EBADF;
+		return NULL;
+	}
+
 	FD_ZERO(&fds);
 	FD_SET(fd,&fds);
 	timeout.tv_sec = t/1000;
diff --git a/source3/nmbd/nmbd_packets.c b/source3/nmbd/nmbd_packets.c
index a753b28..0eafb2c 100644
--- a/source3/nmbd/nmbd_packets.c
+++ b/source3/nmbd/nmbd_packets.c
@@ -1696,7 +1696,7 @@ static bool create_listen_fdset(fd_set **ppset, int **psock_array, int *listen_n
 	/* each interface gets 4 sockets */
 	count *= 4;
 
-	if(count > FD_SETSIZE) {
+	if(count >= FD_SETSIZE) {
 		DEBUG(0,("create_listen_fdset: Too many file descriptors needed (%d). We can \
 only use %d.\n", count, FD_SETSIZE));
 		SAFE_FREE(pset);
@@ -1712,6 +1712,12 @@ only use %d.\n", count, FD_SETSIZE));
 	FD_ZERO(pset);
 
 	/* Add in the lp_socket_address() interface on 137. */
+	if (ClientNMB < 0 || ClientNMB >= FD_SETSIZE) {
+		errno = EBADF;
+		SAFE_FREE(pset);
+		return True;
+	}
+
 	FD_SET(ClientNMB,pset);
 	sock_array[num++] = ClientNMB;
 	*maxfd = MAX( *maxfd, ClientNMB);
@@ -1721,18 +1727,29 @@ only use %d.\n", count, FD_SETSIZE));
 
 	/* Add in the 137 sockets on all the interfaces. */
 	for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec)) {
+		if (subrec->nmb_sock < 0 || subrec->nmb_sock >= FD_SETSIZE) {
+			/* We have to ignore sockets outside FD_SETSIZE. */
+			continue;
+		}
 		FD_SET(subrec->nmb_sock,pset);
 		sock_array[num++] = subrec->nmb_sock;
 		*maxfd = MAX( *maxfd, subrec->nmb_sock);
 
-		sock_array[num++] = subrec->nmb_bcast;
-		if (subrec->nmb_bcast != -1) {
-			FD_SET(subrec->nmb_bcast,pset);
-			*maxfd = MAX( *maxfd, subrec->nmb_bcast);
+		if (subrec->nmb_bcast < 0 || subrec->nmb_bcast >= FD_SETSIZE) {
+			/* We have to ignore sockets outside FD_SETSIZE. */
+			continue;
 		}
+		sock_array[num++] = subrec->nmb_bcast;
+		FD_SET(subrec->nmb_bcast,pset);
+		*maxfd = MAX( *maxfd, subrec->nmb_bcast);
 	}
 
 	/* Add in the lp_socket_address() interface on 138. */
+	if (ClientDGRAM < 0 || ClientDGRAM >= FD_SETSIZE) {
+		errno = EBADF;
+		SAFE_FREE(pset);
+		return True;
+	}
 	FD_SET(ClientDGRAM,pset);
 	sock_array[num++] = ClientDGRAM;
 	*maxfd = MAX( *maxfd, ClientDGRAM);
@@ -1742,10 +1759,18 @@ only use %d.\n", count, FD_SETSIZE));
 
 	/* Add in the 138 sockets on all the interfaces. */
 	for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec)) {
+		if (subrec->dgram_sock < 0 || subrec->dgram_sock >= FD_SETSIZE) {
+			/* We have to ignore sockets outside FD_SETSIZE. */
+			continue;
+		}
 		FD_SET(subrec->dgram_sock,pset);
 		sock_array[num++] = subrec->dgram_sock;
 		*maxfd = MAX( *maxfd, subrec->dgram_sock);
 
+		if (subrec->dgram_bcast < 0 || subrec->dgram_bcast >= FD_SETSIZE) {
+			/* We have to ignore sockets outside FD_SETSIZE. */
+			continue;
+		}
 		sock_array[num++] = subrec->dgram_bcast;
 		if (subrec->dgram_bcast != -1) {
 			FD_SET(subrec->dgram_bcast,pset);
@@ -1876,7 +1901,7 @@ bool listen_for_packets(bool run_election)
 
 #ifndef SYNC_DNS
 	dns_fd = asyncdns_fd();
-	if (dns_fd != -1) {
+	if (dns_fd >= 0 && dns_fd < FD_SETSIZE) {
 		FD_SET(dns_fd, &r_fds);
 		maxfd = MAX( maxfd, dns_fd);
 	}
diff --git a/source3/utils/smbfilter.c b/source3/utils/smbfilter.c
index 65d8461..e7abf52 100644
--- a/source3/utils/smbfilter.c
+++ b/source3/utils/smbfilter.c
@@ -193,8 +193,8 @@ static void filter_child(int c, struct sockaddr_storage *dest_ss)
 		int num;
 		
 		FD_ZERO(&fds);
-		if (s != -1) FD_SET(s, &fds);
-		if (c != -1) FD_SET(c, &fds);
+		if (s >= 0 && s < FD_SETSIZE) FD_SET(s, &fds);
+		if (c >= 0 && c < FD_SETSIZE) FD_SET(c, &fds);
 
 		num = sys_select_intr(MAX(s+1, c+1),&fds,NULL,NULL,NULL);
 		if (num <= 0) continue;
@@ -267,6 +267,9 @@ static void start_filter(char *desthost)
 		socklen_t in_addrlen = sizeof(ss);
 		
 		FD_ZERO(&fds);
+		if (s < 0 || s >= FD_SETSIZE) {
+			break;
+		}
 		FD_SET(s, &fds);
 
 		num = sys_select_intr(s+1,&fds,NULL,NULL,NULL);
diff --git a/source3/winbindd/winbindd_dual.c b/source3/winbindd/winbindd_dual.c
index 44e8552..117d55d 100644
--- a/source3/winbindd/winbindd_dual.c
+++ b/source3/winbindd/winbindd_dual.c
@@ -1460,6 +1460,13 @@ static bool fork_domain_child(struct winbindd_child *child)
 
 		FD_ZERO(&r_fds);
 		FD_ZERO(&w_fds);
+
+		if (state.sock < 0 || state.sock >= FD_SETSIZE) {
+			TALLOC_FREE(frame);
+			perror("EBADF");
+			_exit(1);
+		}
+
 		FD_SET(state.sock, &r_fds);
 		maxfd = state.sock;
 


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