commit 7e191387d64de2c965fc2c999bc7d1ccf4aae010 Author: Gerald W. Carter Date: Wed May 28 07:30:19 2008 -0500 Security: Patche for CVE-2008-1105. -- Summary -- Specifically crafted SMB responses can result in a heap overflow in the Samba client code. Because the server process, smbd, can itself act as a client during operations such as printer notification and domain authentication, this issue affects both Samba client and server installations. Ensure that we specify the buffer size used to store incoming SMB packets. This bug was originally introduced in Samba 2.2.4. Patch from Jeremy Allison. diff --git a/source/client/client.c b/source/client/client.c index 3f96f63..e87623a 100644 --- a/source/client/client.c +++ b/source/client/client.c @@ -3626,7 +3626,7 @@ static void readline_callback(void) session keepalives and then drop them here. */ if (FD_ISSET(cli->fd,&fds)) { - if (!receive_smb(cli->fd,cli->inbuf,0)) { + if (!receive_smb(cli->fd,cli->inbuf,cli->bufsize,0)) { DEBUG(0, ("Read from server failed, maybe it closed the " "connection\n")); return; diff --git a/source/client/smbctool.c b/source/client/smbctool.c index 2063418..a18505b 100644 --- a/source/client/smbctool.c +++ b/source/client/smbctool.c @@ -3304,7 +3304,7 @@ static void readline_callback(void) session keepalives and then drop them here. */ if (FD_ISSET(cli->fd,&fds)) { - receive_smb(cli->fd,cli->inbuf,0); + receive_smb(cli->fd,cli->inbuf,cli->bufsize,0); goto again; } diff --git a/source/lib/util_sock.c b/source/lib/util_sock.c index 94c5e82..4715ca7 100644 --- a/source/lib/util_sock.c +++ b/source/lib/util_sock.c @@ -654,14 +654,13 @@ ssize_t read_smb_length(int fd, char *inbuf, unsigned int timeout) } /**************************************************************************** - Read an smb from a fd. Note that the buffer *MUST* be of size - BUFFER_SIZE+SAFETY_MARGIN. + Read an smb from a fd. The timeout is in milliseconds. This function will return on receipt of a session keepalive packet. Doesn't check the MAC on signed packets. ****************************************************************************/ -BOOL receive_smb_raw(int fd, char *buffer, unsigned int timeout) +BOOL receive_smb_raw(int fd, char *buffer, size_t buflen, unsigned int timeout) { ssize_t len,ret; @@ -682,25 +681,18 @@ BOOL receive_smb_raw(int fd, char *buffer, unsigned int timeout) return False; } - /* - * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes - * of header. Don't print the error if this fits.... JRA. - */ - - if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) { + if (len > buflen) { DEBUG(0,("Invalid packet length! (%lu bytes).\n",(unsigned long)len)); - if (len > BUFFER_SIZE + (SAFETY_MARGIN/2)) { - /* - * Correct fix. smb_read_error may have already been - * set. Only set it here if not already set. Global - * variables still suck :-). JRA. - */ + /* + * smb_read_error may have already been + * set. Only set it here if not already set. Global + * variables still suck :-). JRA. + */ - if (smb_read_error == 0) - smb_read_error = READ_ERROR; - return False; - } + if (smb_read_error == 0) + smb_read_error = READ_ERROR; + return False; } if(len > 0) { @@ -730,9 +722,9 @@ BOOL receive_smb_raw(int fd, char *buffer, unsigned int timeout) Checks the MAC on signed packets. ****************************************************************************/ -BOOL receive_smb(int fd, char *buffer, unsigned int timeout) +BOOL receive_smb(int fd, char *buffer, size_t buflen, unsigned int timeout) { - if (!receive_smb_raw(fd, buffer, timeout)) { + if (!receive_smb_raw(fd, buffer, buflen, timeout)) { return False; } diff --git a/source/libsmb/clientgen.c b/source/libsmb/clientgen.c index c6cef08..7d7ab9e 100644 --- a/source/libsmb/clientgen.c +++ b/source/libsmb/clientgen.c @@ -44,8 +44,7 @@ int cli_set_port(struct cli_state *cli, int port) } /**************************************************************************** - Read an smb from a fd ignoring all keepalive packets. Note that the buffer - *MUST* be of size BUFFER_SIZE+SAFETY_MARGIN. + Read an smb from a fd ignoring all keepalive packets. The timeout is in milliseconds This is exactly the same as receive_smb except that it never returns @@ -54,12 +53,12 @@ int cli_set_port(struct cli_state *cli, int port) should never go into a blocking read. ****************************************************************************/ -static BOOL client_receive_smb(int fd,char *buffer, unsigned int timeout) +static BOOL client_receive_smb(int fd,char *buffer, size_t bufsize, unsigned int timeout) { BOOL ret; for(;;) { - ret = receive_smb_raw(fd, buffer, timeout); + ret = receive_smb_raw(fd, buffer, bufsize, timeout); if (!ret) { DEBUG(10,("client_receive_smb failed\n")); @@ -88,7 +87,7 @@ BOOL cli_receive_smb(struct cli_state *cli) return False; again: - ret = client_receive_smb(cli->fd,cli->inbuf,cli->timeout); + ret = client_receive_smb(cli->fd,cli->inbuf, cli->bufsize, cli->timeout); if (ret) { /* it might be an oplock break request */ diff --git a/source/smbd/process.c b/source/smbd/process.c index 8dec719..3d31c29 100644 --- a/source/smbd/process.c +++ b/source/smbd/process.c @@ -521,7 +521,8 @@ static BOOL receive_message_or_smb(char *buffer, int buffer_len, int timeout) goto again; } - return receive_smb(smbd_server_fd(), buffer, 0); + return receive_smb(smbd_server_fd(), buffer, + BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE, 0); } /* diff --git a/source/utils/smbfilter.c b/source/utils/smbfilter.c index 97d2223..2152e53 100644 --- a/source/utils/smbfilter.c +++ b/source/utils/smbfilter.c @@ -140,7 +140,7 @@ static void filter_child(int c, struct in_addr dest_ip) if (num <= 0) continue; if (c != -1 && FD_ISSET(c, &fds)) { - if (!receive_smb(c, packet, 0)) { + if (!receive_smb(c, packet, BUFFER_SIZE, 0)) { d_printf("client closed connection\n"); exit(0); } @@ -151,7 +151,7 @@ static void filter_child(int c, struct in_addr dest_ip) } } if (s != -1 && FD_ISSET(s, &fds)) { - if (!receive_smb(s, packet, 0)) { + if (!receive_smb(s, packet, BUFFER_SIZE, 0)) { d_printf("server closed connection\n"); exit(0); }