samba: add security fix for CVE-2011-0719

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
This commit is contained in:
Gustavo Zacarias 2011-03-04 11:22:25 -03:00 committed by Peter Korsgaard
parent 7bdbdd3c38
commit a3cd2e7671

View File

@ -0,0 +1,613 @@
From 724e44eed299c618066dec411530aa9f156119ec Mon Sep 17 00:00:00 2001
From: Karolin Seeger <kseeger@samba.org>
Date: Sun, 27 Feb 2011 18:28:29 +0100
Subject: [PATCH] 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.
---
source/client/client.c | 4 +++-
source/client/dnsbrowse.c | 12 ++++++++++++
source/lib/events.c | 13 +++++++++++++
source/lib/packet.c | 5 +++++
source/lib/readline.c | 5 +++++
source/lib/select.c | 6 ++++++
source/lib/util_sock.c | 11 +++++++++--
source/libaddns/dnssock.c | 6 +++++-
source/libsmb/nmblib.c | 5 +++++
source/nmbd/nmbd_packets.c | 24 ++++++++++++++++++++++--
source/nsswitch/wb_common.c | 22 ++++++++++++++++++++--
source/printing/printing.c | 5 +++++
source/smbd/dnsregister.c | 6 ++++++
source/smbd/oplock.c | 5 ++++-
source/smbd/oplock_irix.c | 5 +++++
source/smbd/process.c | 2 +-
source/smbd/server.c | 29 +++++++++++++++++++++--------
source/utils/smbfilter.c | 8 ++++++--
source/winbindd/winbindd.c | 12 +++++++++++-
source/winbindd/winbindd_dual.c | 7 +++++++
20 files changed, 171 insertions(+), 21 deletions(-)
diff --git a/source/client/client.c b/source/client/client.c
index 53bd9e6..a989441 100644
--- a/source/client/client.c
+++ b/source/client/client.c
@@ -4379,8 +4379,10 @@ 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/source/client/dnsbrowse.c b/source/client/dnsbrowse.c
index 5e3a4de..aa2fb22 100644
--- a/source/client/dnsbrowse.c
+++ b/source/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);
@@ -183,6 +188,13 @@ int do_smb_browse(void)
fdsetsz = howmany(mdnsfd + 1, NFDBITS) * sizeof(fd_mask);
fdset = TALLOC_ZERO(ctx, fdsetsz);
+
+ if (mdnsfd < 0 || mdnsfd >= FD_SETSIZE) {
+ errno = EBADF;
+ TALLOC_FREE(ctx);
+ return 1;
+ }
+
FD_SET(mdnsfd, fdset);
tv.tv_sec = 1;
diff --git a/source/lib/events.c b/source/lib/events.c
index cd20ceb..2ddbab7 100644
--- a/source/lib/events.c
+++ b/source/lib/events.c
@@ -140,6 +140,11 @@ struct fd_event *event_add_fd(struct event_context *event_ctx,
{
struct fd_event *fde;
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ errno = EBADF;
+ return NULL;
+ }
+
if (!(fde = TALLOC_P(mem_ctx, struct fd_event))) {
return NULL;
}
@@ -190,6 +195,14 @@ bool event_add_to_select_args(struct event_context *event_ctx,
bool ret = False;
for (fde = event_ctx->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/source/lib/packet.c b/source/lib/packet.c
index e048616..512c7f2 100644
--- a/source/lib/packet.c
+++ b/source/lib/packet.c
@@ -106,6 +106,11 @@ 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/source/lib/readline.c b/source/lib/readline.c
index 34867aa..70a82f2 100644
--- a/source/lib/readline.c
+++ b/source/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/source/lib/select.c b/source/lib/select.c
index c3da6a9..2d5f02c 100644
--- a/source/lib/select.c
+++ b/source/lib/select.c
@@ -61,6 +61,11 @@ int sys_select(int maxfd, fd_set *readfds, fd_set *writefds, fd_set *errorfds, s
if (pipe(select_pipe) == -1)
smb_panic("Could not create select pipe");
+ if (select_pipe[0] < 0 || select_pipe[0] >= FD_SETSIZE) {
+ 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
@@ -87,6 +92,7 @@ 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/source/lib/util_sock.c b/source/lib/util_sock.c
index 650bd13..8aa2c97 100644
--- a/source/lib/util_sock.c
+++ b/source/lib/util_sock.c
@@ -960,6 +960,11 @@ NTSTATUS read_socket_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);
@@ -1492,7 +1497,7 @@ 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);
}
@@ -1541,8 +1546,10 @@ 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)
diff --git a/source/libaddns/dnssock.c b/source/libaddns/dnssock.c
index 7c8bd41..f427bd5 100644
--- a/source/libaddns/dnssock.c
+++ b/source/libaddns/dnssock.c
@@ -218,7 +218,11 @@ static DNS_ERROR read_all(int fd, uint8 *data, size_t len)
while (total < len) {
ssize_t ret;
int fd_ready;
-
+
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ return ERROR_DNS_SOCKET_ERROR;
+ }
+
FD_ZERO( &rfds );
FD_SET( fd, &rfds );
diff --git a/source/libsmb/nmblib.c b/source/libsmb/nmblib.c
index bfe5e7b..768e54d 100644
--- a/source/libsmb/nmblib.c
+++ b/source/libsmb/nmblib.c
@@ -1097,6 +1097,11 @@ 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/source/nmbd/nmbd_packets.c b/source/nmbd/nmbd_packets.c
index 4b97819..03e5362 100644
--- a/source/nmbd/nmbd_packets.c
+++ b/source/nmbd/nmbd_packets.c
@@ -1683,7 +1683,7 @@ static bool create_listen_fdset(fd_set **ppset, int **psock_array, int *listen_n
for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec))
count++;
- if((count*2) + 2 > FD_SETSIZE) {
+ if((count*2) + 2 >= FD_SETSIZE) {
DEBUG(0,("create_listen_fdset: Too many file descriptors needed (%d). We can \
only use %d.\n", (count*2) + 2, FD_SETSIZE));
SAFE_FREE(pset);
@@ -1699,24 +1699,44 @@ only use %d.\n", (count*2) + 2, FD_SETSIZE));
FD_ZERO(pset);
/* Add in the broadcast socket 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);
/* 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);
}
/* Add in the broadcast socket 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);
/* 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);
@@ -1767,7 +1787,7 @@ 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/source/nsswitch/wb_common.c b/source/nsswitch/wb_common.c
index a164621..4f76bd0 100644
--- a/source/nsswitch/wb_common.c
+++ b/source/nsswitch/wb_common.c
@@ -240,6 +240,12 @@ static int winbind_named_pipe_sock(const char *dir)
switch (errno) {
case EINPROGRESS:
+
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ errno = EBADF;
+ goto error_out;
+ }
+
FD_ZERO(&w_fds);
FD_SET(fd, &w_fds);
tv.tv_sec = CONNECT_TIMEOUT - wait_time;
@@ -383,7 +389,13 @@ int winbind_write_sock(void *buffer, int count, int recursing, int need_priv)
while(nwritten < count) {
struct timeval tv;
fd_set r_fds;
-
+
+ if (winbindd_fd < 0 || winbindd_fd >= FD_SETSIZE) {
+ errno = EBADF;
+ winbind_close_sock();
+ return -1;
+ }
+
/* Catch pipe close on other end by checking if a read()
call would not block by calling select(). */
@@ -443,7 +455,13 @@ int winbind_read_sock(void *buffer, int count)
while(nread < count) {
struct timeval tv;
fd_set r_fds;
-
+
+ if (winbindd_fd < 0 || winbindd_fd >= FD_SETSIZE) {
+ errno = EBADF;
+ winbind_close_sock();
+ return -1;
+ }
+
/* Catch pipe close on other end by checking if a read()
call would not block by calling select(). */
diff --git a/source/printing/printing.c b/source/printing/printing.c
index a9272eb..c3b8c61 100644
--- a/source/printing/printing.c
+++ b/source/printing/printing.c
@@ -1407,6 +1407,11 @@ void start_background_queue(void)
exit(1);
}
+ if (pause_pipe[1] < 0 || pause_pipe[1] >= FD_SETSIZE) {
+ DEBUG(5,("start_background_queue: pipe fd out of range.\n"));
+ exit(1);
+ }
+
background_lpq_updater_pid = sys_fork();
if (background_lpq_updater_pid == -1) {
diff --git a/source/smbd/dnsregister.c b/source/smbd/dnsregister.c
index f02739e..3c689b9 100644
--- a/source/smbd/dnsregister.c
+++ b/source/smbd/dnsregister.c
@@ -125,6 +125,9 @@ void dns_register_smbd(struct dns_reg_state ** dns_state_ptr,
*/
if (dns_state->srv_ref != NULL) {
mdnsd_conn_fd = DNSServiceRefSockFD(dns_state->srv_ref);
+ if (mdnsd_conn_fd < 0 || mdnsd_conn_fd >= FD_SETSIZE) {
+ return;
+ }
FD_SET(mdnsd_conn_fd, listen_set);
return;
}
@@ -156,6 +159,9 @@ void dns_register_smbd(struct dns_reg_state ** dns_state_ptr,
}
mdnsd_conn_fd = DNSServiceRefSockFD(dns_state->srv_ref);
+ if (mdnsd_conn_fd < 0 || mdnsd_conn_fd >= FD_SETSIZE) {
+ return;
+ }
FD_SET(mdnsd_conn_fd, listen_set);
*maxfd = MAX(*maxfd, mdnsd_conn_fd);
*timeout = timeval_zero();
diff --git a/source/smbd/oplock.c b/source/smbd/oplock.c
index a07d05d..5ae3fdf 100644
--- a/source/smbd/oplock.c
+++ b/source/smbd/oplock.c
@@ -241,7 +241,10 @@ bool downgrade_oplock(files_struct *fsp)
int oplock_notify_fd(void)
{
if (koplocks) {
- return koplocks->notification_fd;
+ int fd = koplocks->notification_fd;
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ return -1;
+ }
}
return -1;
diff --git a/source/smbd/oplock_irix.c b/source/smbd/oplock_irix.c
index 8c287c9..6e86fac 100644
--- a/source/smbd/oplock_irix.c
+++ b/source/smbd/oplock_irix.c
@@ -284,6 +284,11 @@ struct kernel_oplocks *irix_init_kernel_oplocks(void)
return False;
}
+ if (pfd[0] < 0 || pfd[0] >= FD_SETSIZE) {
+ DEBUG(0,("setup_kernel_oplock_pipe: fd out of range.\n"));
+ return False;
+ }
+
oplock_pipe_read = pfd[0];
oplock_pipe_write = pfd[1];
diff --git a/source/smbd/process.c b/source/smbd/process.c
index 403c7c6..9b8f29b 100644
--- a/source/smbd/process.c
+++ b/source/smbd/process.c
@@ -698,7 +698,7 @@ static void async_processing(fd_set *pfds)
static int select_on_fd(int fd, int maxfd, fd_set *fds)
{
- if (fd != -1) {
+ if (fd != -1 && fd < FD_SETSIZE) {
FD_SET(fd, fds);
maxfd = MAX(maxfd, fd);
}
diff --git a/source/smbd/server.c b/source/smbd/server.c
index 5129484..a670334 100644
--- a/source/smbd/server.c
+++ b/source/smbd/server.c
@@ -209,7 +209,13 @@ static bool open_sockets_inetd(void)
/* Started from inetd. fd 0 is the socket. */
/* We will abort gracefully when the client or remote system
goes away */
- smbd_set_server_fd(dup(0));
+ int fd = dup(0);
+
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ return false;
+ }
+
+ smbd_set_server_fd(fd);
/* close our standard file descriptors */
close_low_fds(False); /* Don't close stderr */
@@ -436,7 +442,8 @@ static bool open_sockets_smbd(bool is_daemon, bool interactive, const char *smb_
num_sockets == 0 ? 0 : 2,
ifss,
true);
- if(s == -1) {
+ if(s < 0 || s >= FD_SETSIZE) {
+ close(s);
continue;
}
@@ -516,7 +523,7 @@ static bool open_sockets_smbd(bool is_daemon, bool interactive, const char *smb_
num_sockets == 0 ? 0 : 2,
&ss,
true);
- if (s == -1) {
+ if (s < 0 || s >= FD_SETSIZE) {
continue;
}
@@ -709,6 +716,7 @@ static bool open_sockets_smbd(bool is_daemon, bool interactive, const char *smb_
struct sockaddr addr;
socklen_t in_addrlen = sizeof(addr);
pid_t child = 0;
+ int fd;
s = -1;
for(i = 0; i < num_sockets; i++) {
@@ -721,16 +729,21 @@ static bool open_sockets_smbd(bool is_daemon, bool interactive, const char *smb_
}
}
- smbd_set_server_fd(accept(s,&addr,&in_addrlen));
-
- if (smbd_server_fd() == -1 && errno == EINTR)
+ fd = accept(s,&addr,&in_addrlen);
+ if (fd == -1 && errno == EINTR)
continue;
-
- if (smbd_server_fd() == -1) {
+ if (fd == -1) {
DEBUG(2,("open_sockets_smbd: accept: %s\n",
strerror(errno)));
continue;
}
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ DEBUG(2,("open_sockets_smbd: bad fd %d\n",
+ fd ));
+ continue;
+ }
+
+ smbd_set_server_fd(fd);
/* Ensure child is set to blocking mode */
set_blocking(smbd_server_fd(),True);
diff --git a/source/utils/smbfilter.c b/source/utils/smbfilter.c
index 1e22a40..45f9207 100644
--- a/source/utils/smbfilter.c
+++ b/source/utils/smbfilter.c
@@ -162,8 +162,8 @@ 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;
@@ -235,6 +235,10 @@ static void start_filter(char *desthost)
struct sockaddr_storage ss;
socklen_t in_addrlen = sizeof(ss);
+ if (s < 0 || s >= FD_SETSIZE) {
+ break;
+ }
+
FD_ZERO(&fds);
FD_SET(s, &fds);
diff --git a/source/winbindd/winbindd.c b/source/winbindd/winbindd.c
index 1d618e2..6b5c251 100644
--- a/source/winbindd/winbindd.c
+++ b/source/winbindd/winbindd.c
@@ -836,7 +836,8 @@ static void process_loop(void)
listen_sock = open_winbindd_socket();
listen_priv_sock = open_winbindd_priv_socket();
- if (listen_sock == -1 || listen_priv_sock == -1) {
+ if (listen_sock < 0 || listen_sock >= FD_SETSIZE ||
+ listen_priv_sock < 0 || listen_priv_sock >= FD_SETSIZE) {
perror("open_winbind_socket");
exit(1);
}
@@ -861,6 +862,9 @@ static void process_loop(void)
FD_ZERO(&r_fds);
FD_ZERO(&w_fds);
+
+ /* We check the range for listen_sock and
+ listen_priv_sock above. */
FD_SET(listen_sock, &r_fds);
FD_SET(listen_priv_sock, &r_fds);
@@ -890,6 +894,12 @@ static void process_loop(void)
}
for (ev = fd_events; ev; ev = ev->next) {
+ if (ev->fd < 0 || ev->fd >= FD_SETSIZE) {
+ /* Ignore here - event_add_to_select_args
+ should make this impossible. */
+ continue;
+ }
+
if (ev->flags & EVENT_FD_READ) {
FD_SET(ev->fd, &r_fds);
maxfd = MAX(ev->fd, maxfd);
diff --git a/source/winbindd/winbindd_dual.c b/source/winbindd/winbindd_dual.c
index ff004f2..b30ec20 100644
--- a/source/winbindd/winbindd_dual.c
+++ b/source/winbindd/winbindd_dual.c
@@ -1250,6 +1250,12 @@ static bool fork_domain_child(struct winbindd_child *child)
return False;
}
+ if (fdpair[0] < 0 || fdpair[0] >= FD_SETSIZE) {
+ DEBUG(0, ("fork_domain_child: bad fd range (%d)\n", fdpair[0]));
+ errno = EBADF;
+ return False;
+ }
+
ZERO_STRUCT(state);
state.pid = sys_getpid();
@@ -1405,6 +1411,7 @@ static bool fork_domain_child(struct winbindd_child *child)
message_dispatch(winbind_messaging_context());
FD_ZERO(&read_fds);
+ /* We check state.sock against FD_SETSIZE above. */
FD_SET(state.sock, &read_fds);
ret = sys_select(state.sock + 1, &read_fds, NULL, NULL, tp);
--
1.6.4.2