From 118213c059501d384be9a6dcaf02d13a681bedc3 Mon Sep 17 00:00:00 2001 From: Jeremy Allison Date: Thu, 22 Jan 1998 09:25:05 +0000 Subject: printing.c: Bug fix for lpng reporting. server.c: Large fix for oplock deadlock bug. util.c: Fix for oplock deadlock bug. Jeremy. (This used to be commit 4cae830ab3a942b2f2868173a492d02f6332651d) --- source3/smbd/server.c | 106 +++++++++++++++++++++++++++++++------------------- 1 file changed, 67 insertions(+), 39 deletions(-) (limited to 'source3/smbd') diff --git a/source3/smbd/server.c b/source3/smbd/server.c index 751039070f..b5408a2903 100644 --- a/source3/smbd/server.c +++ b/source3/smbd/server.c @@ -2963,6 +2963,16 @@ inode = %x).\n", timestring(), fsp->name, fnum, dev, inode)); shutdown_server = True; break; } + + /* + * There are certain SMB requests that we shouldn't allow + * to recurse. opens, renames and deletes are the obvious + * ones. This is handled in the switch_message() function. + * If global_oplock_break is set they will push the packet onto + * the pending smb queue and return -1 (no reply). + * JRA. + */ + process_smb(inbuf, outbuf); /* @@ -3036,6 +3046,8 @@ BOOL request_oplock_break(share_mode_entry *share_entry, char op_break_msg[OPLOCK_BREAK_MSG_LEN]; struct sockaddr_in addr_out; int pid = getpid(); + time_t start_time; + int time_left; if(pid == share_entry->pid) { @@ -3089,7 +3101,10 @@ to pid %d on port %d for dev = %x, inode = %x. Error was %s\n", * While we get messages that aren't ours, loop. */ - while(1) + start_time = time(NULL); + time_left = OPLOCK_BREAK_TIMEOUT+OPLOCK_BREAK_TIMEOUT_FUDGEFACTOR; + + while(time_left >= 0) { char op_break_reply[UDP_CMD_HEADER_LEN+OPLOCK_BREAK_MSG_LEN]; int32 reply_msg_len; @@ -3097,7 +3112,7 @@ to pid %d on port %d for dev = %x, inode = %x. Error was %s\n", char *reply_msg_start; if(receive_local_message(oplock_sock, op_break_reply, sizeof(op_break_reply), - (OPLOCK_BREAK_TIMEOUT+OPLOCK_BREAK_TIMEOUT_FUDGEFACTOR) * 1000) == False) + time_left ? time_left * 1000 : 1) == False) { if(smb_read_error == READ_TIMEOUT) { @@ -3120,23 +3135,6 @@ pid %d on port %d for dev = %x, inode = %x. Error was (%s).\n", timestring, shar return False; } - /* - * If the response we got was not an answer to our message, but - * was a completely different request, push it onto the pending - * udp message stack so that we can deal with it in the main loop. - * It may be another oplock break request to us. - */ - - /* - * Local note from JRA. There exists the possibility of a denial - * of service attack here by allowing non-root processes running - * on a local machine sending many of these pending messages to - * a smbd port. Currently I'm not sure how to restrict the messages - * I will queue (although I could add a limit to the queue) to - * those received by root processes only. There should be a - * way to make this bulletproof.... - */ - reply_msg_len = IVAL(op_break_reply,UDP_CMD_LEN_OFFSET); reply_from_port = SVAL(op_break_reply,UDP_CMD_PORT_OFFSET); @@ -3150,21 +3148,37 @@ pid %d on port %d for dev = %x, inode = %x. Error was (%s).\n", timestring, shar continue; } - if(((SVAL(reply_msg_start,UDP_MESSAGE_CMD_OFFSET) & CMD_REPLY) == 0) || - (reply_from_port != share_entry->op_port) || + /* + * Test to see if this is the reply we are awaiting. + */ + + if((SVAL(reply_msg_start,UDP_MESSAGE_CMD_OFFSET) & CMD_REPLY) && + (reply_from_port == share_entry->op_port) && (memcmp(&reply_msg_start[OPLOCK_BREAK_PID_OFFSET], &op_break_msg[OPLOCK_BREAK_PID_OFFSET], - OPLOCK_BREAK_MSG_LEN - OPLOCK_BREAK_PID_OFFSET) != 0)) + OPLOCK_BREAK_MSG_LEN - OPLOCK_BREAK_PID_OFFSET) == 0)) { - DEBUG(3,("%s request_oplock_break: received other message whilst awaiting \ -oplock break response from pid %d on port %d for dev = %x, inode = %x.\n", - timestring(), share_entry->pid, share_entry->op_port, dev, inode)); - if(push_local_message(op_break_reply, sizeof(op_break_reply)) == False) - return False; - continue; + /* + * This is the reply we've been waiting for. + */ + break; } + else + { + /* + * This is another message - probably a break request. + * Process it to prevent potential deadlock. + * Note that the code in switch_message() prevents + * us from recursing into here as any SMB requests + * we might process that would cause another oplock + * break request to be made will be queued. + * JRA. + */ - break; + process_local_message(oplock_sock, op_break_reply, sizeof(op_break_reply)); + } + + time_left -= (time(NULL) - start_time); } DEBUG(3,("%s request_oplock_break: broke oplock.\n", timestring())); @@ -4522,7 +4536,7 @@ force write permissions on print services. #define TIME_INIT (1<<2) #define CAN_IPC (1<<3) #define AS_GUEST (1<<5) - +#define QUEUE_IN_OPLOCK (1<<6) /* define a list of possible SMB messages and their corresponding @@ -4556,20 +4570,20 @@ struct smb_message_struct {SMBsetatr,"SMBsetatr",reply_setatr,AS_USER | NEED_WRITE}, {SMBchkpth,"SMBchkpth",reply_chkpth,AS_USER}, {SMBsearch,"SMBsearch",reply_search,AS_USER}, - {SMBopen,"SMBopen",reply_open,AS_USER}, + {SMBopen,"SMBopen",reply_open,AS_USER | QUEUE_IN_OPLOCK }, /* note that SMBmknew and SMBcreate are deliberately overloaded */ {SMBcreate,"SMBcreate",reply_mknew,AS_USER}, {SMBmknew,"SMBmknew",reply_mknew,AS_USER}, - {SMBunlink,"SMBunlink",reply_unlink,AS_USER | NEED_WRITE}, + {SMBunlink,"SMBunlink",reply_unlink,AS_USER | NEED_WRITE | QUEUE_IN_OPLOCK}, {SMBread,"SMBread",reply_read,AS_USER}, {SMBwrite,"SMBwrite",reply_write,AS_USER}, {SMBclose,"SMBclose",reply_close,AS_USER | CAN_IPC}, {SMBmkdir,"SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE}, {SMBrmdir,"SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE}, {SMBdskattr,"SMBdskattr",reply_dskattr,AS_USER}, - {SMBmv,"SMBmv",reply_mv,AS_USER | NEED_WRITE}, + {SMBmv,"SMBmv",reply_mv,AS_USER | NEED_WRITE | QUEUE_IN_OPLOCK}, /* this is a Pathworks specific call, allowing the changing of the root path */ @@ -4577,8 +4591,8 @@ struct smb_message_struct {SMBlseek,"SMBlseek",reply_lseek,AS_USER}, {SMBflush,"SMBflush",reply_flush,AS_USER}, - {SMBctemp,"SMBctemp",reply_ctemp,AS_USER}, - {SMBsplopen,"SMBsplopen",reply_printopen,AS_USER}, + {SMBctemp,"SMBctemp",reply_ctemp,AS_USER | QUEUE_IN_OPLOCK }, + {SMBsplopen,"SMBsplopen",reply_printopen,AS_USER | QUEUE_IN_OPLOCK }, {SMBsplclose,"SMBsplclose",reply_printclose,AS_USER}, {SMBsplretq,"SMBsplretq",reply_printqueue,AS_USER|AS_GUEST}, {SMBsplwr,"SMBsplwr",reply_printwrite,AS_USER}, @@ -4605,10 +4619,10 @@ struct smb_message_struct {SMBtrans,"SMBtrans",reply_trans,AS_USER | CAN_IPC}, {SMBtranss,"SMBtranss",NULL,AS_USER | CAN_IPC}, {SMBioctls,"SMBioctls",NULL,AS_USER}, - {SMBcopy,"SMBcopy",reply_copy,AS_USER | NEED_WRITE}, - {SMBmove,"SMBmove",NULL,AS_USER | NEED_WRITE}, + {SMBcopy,"SMBcopy",reply_copy,AS_USER | NEED_WRITE | QUEUE_IN_OPLOCK }, + {SMBmove,"SMBmove",NULL,AS_USER | NEED_WRITE | QUEUE_IN_OPLOCK }, - {SMBopenX,"SMBopenX",reply_open_and_X,AS_USER | CAN_IPC}, + {SMBopenX,"SMBopenX",reply_open_and_X,AS_USER | CAN_IPC | QUEUE_IN_OPLOCK }, {SMBreadX,"SMBreadX",reply_read_and_X,AS_USER}, {SMBwriteX,"SMBwriteX",reply_write_and_X,AS_USER}, {SMBlockingX,"SMBlockingX",reply_lockingX,AS_USER}, @@ -4620,7 +4634,7 @@ struct smb_message_struct /* LANMAN2.0 PROTOCOL FOLLOWS */ {SMBfindnclose, "SMBfindnclose", reply_findnclose, AS_USER}, {SMBfindclose, "SMBfindclose", reply_findclose,AS_USER}, - {SMBtrans2, "SMBtrans2", reply_trans2, AS_USER}, + {SMBtrans2, "SMBtrans2", reply_trans2, AS_USER | QUEUE_IN_OPLOCK }, {SMBtranss2, "SMBtranss2", reply_transs2, AS_USER}, /* messaging routines */ @@ -4702,6 +4716,20 @@ static int switch_message(int type,char *inbuf,char *outbuf,int size,int bufsize else { DEBUG(3,("switch message %s (pid %d)\n",smb_messages[match].name,pid)); + + if(global_oplock_break && (smb_messages[match].flags & QUEUE_IN_OPLOCK)) + { + /* + * Queue this message as we are the process of an oplock break. + */ + + DEBUG(2,("%s: switch_message: queueing message due to being in oplock break state.\n", + timestring() )); + + push_smb_message( inbuf, size); + return -1; + } + if (smb_messages[match].fn) { int cnum = SVAL(inbuf,smb_tid); -- cgit