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locking.c: Added fix for race condition in slow share mode code.

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lsaparse.c: #ifdef'ed out code so this will compile - LUKE PLEASE CHECK THIS.
pipes.c: #ifdef'ed out code so this will compile - LUKE PLEASE CHECK THIS.
server.c: Fixed last known oplock race condition.
smb.h: Re-removed USE_OPLOCK defines - someone checked in an old version.
smbparse.c: #ifdef'ed out code so this will compile - LUKE PLEASE CHECK THIS.
Jeremy (jallison@whistle.com)
This commit is contained in:
Jeremy Allison -
parent bef12478d2
commit 1e1366ddc5
6 changed files with 93 additions and 30 deletions
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15
source/include/smb.h
View File

@ -1042,10 +1042,8 @@ typedef struct
{
smb_shm_offset_t next_share_mode_entry;
int pid;
#ifdef USE_OPLOCKS
uint16 op_port;
uint16 op_type;
#endif /* USE_OPLOCKS */
int share_mode;
struct timeval time;
} share_mode_entry;
@ -1054,10 +1052,8 @@ typedef struct
typedef struct
{
int pid;
#ifdef USE_OPLOCKS
uint16 op_port;
uint16 op_type;
#endif /* USE_OPLOCKS */
int share_mode;
struct timeval time;
} min_share_mode_entry;
@ -1083,11 +1079,7 @@ struct connect_record
};
#ifndef LOCKING_VERSION
#ifdef USE_OPLOCKS
#define LOCKING_VERSION 4
#else /* USE_OPLOCKS */
#define LOCKING_VERSION 3
#endif /* USE_OPLOCKS */
#endif /* LOCKING_VERSION */
#if !defined(FAST_SHARE_MODES)
@ -1103,11 +1095,7 @@ struct connect_record
#define SMF_FILENAME_LEN_OFFSET 8
#define SMF_HEADER_LENGTH 10
#ifdef USE_OPLOCKS
#define SMF_ENTRY_LENGTH 20
#else /* USE_OPLOCKS */
#define SMF_ENTRY_LENGTH 16
#endif /* USE_OPLOCKS */
/*
* Share mode record offsets.
@ -1117,11 +1105,8 @@ struct connect_record
#define SME_USEC_OFFSET 4
#define SME_SHAREMODE_OFFSET 8
#define SME_PID_OFFSET 12
#ifdef USE_OPLOCKS
#define SME_PORT_OFFSET 16
#define SME_OPLOCK_TYPE_OFFSET 18
#endif /* USE_OPLOCKS */
#endif /* FAST_SHARE_MODES */

71
source/locking/locking.c
View File

@ -25,6 +25,10 @@
May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
locking to deal with multiple share modes per open file.
September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
support.
*/
#include "includes.h"
@ -726,13 +730,60 @@ BOOL lock_share_entry(int cnum, uint32 dev, uint32 inode, share_lock_token *ptok
{
int old_umask;
BOOL gotlock = False;
unbecome_user();
old_umask = umask(0);
/*
* There was a race condition in the original slow share mode code.
* A smbd could open a share mode file, and before getting
* the lock, another smbd could delete the last entry for
* the share mode file and delete the file entry from the
* directory. Thus this smbd would be left with a locked
* share mode fd attached to a file that no longer had a
* directory entry. Thus another smbd would think that
* there were no outstanding opens on the file. To fix
* this we now check we can do a stat() call on the filename
* before allowing the lock to proceed, and back out completely
* and try the open again if we cannot.
* Jeremy Allison (jallison@whistle.com).
*/
do
{
struct stat dummy_stat;
#ifdef SECURE_SHARE_MODES
fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0600);
fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0600);
#else /* SECURE_SHARE_MODES */
fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0666);
fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0666);
#endif /* SECURE_SHARE_MODES */
/* At this point we have an open fd to the share mode file.
Lock the first byte exclusively to signify a lock. */
if(fcntl_lock(fd, F_SETLKW, 0, 1, F_WRLCK) == False)
{
DEBUG(0,("ERROR lock_share_entry: fcntl_lock on file %s failed with %s\n",
fname, strerror(errno)));
close(fd);
return False;
}
/*
* If we cannot stat the filename, the file was deleted between
* the open and the lock call. Back out and try again.
*/
if(stat(fname, &dummy_stat)!=0)
{
DEBUG(2,("lock_share_entry: Re-issuing open on %s to fix race. Error was %s\n",
fname, strerror(errno)));
close(fd);
}
else
gotlock = True;
} while(!gotlock);
umask(old_umask);
if(!become_user(cnum,Connections[cnum].vuid))
{
@ -750,18 +801,8 @@ BOOL lock_share_entry(int cnum, uint32 dev, uint32 inode, share_lock_token *ptok
}
}
/* At this point we have an open fd to the share mode file.
Lock the first byte exclusively to signify a lock. */
if(fcntl_lock(fd, F_SETLKW, 0, 1, F_WRLCK) == False)
{
DEBUG(0,("ERROR lock_share_entry: fcntl_lock failed with %s\n",
strerror(errno)));
close(fd);
return False;
}
*ptok = (share_lock_token)fd;
return True;
*ptok = (share_lock_token)fd;
return True;
}
/*******************************************************************
@ -781,7 +822,7 @@ BOOL unlock_share_entry(int cnum, uint32 dev, uint32 inode, share_lock_token tok
ret = False;
}
close((int)token);
close(fd);
return ret;
}

2
source/lsaparse.c
View File

@ -24,6 +24,7 @@
extern int DEBUGLEVEL;
#if 0 /* NEED TO DO THIS TO GET A COMPILE - LUKE PLEASE CHECK THIS !!! */
/*******************************************************************
reads or writes an LSA_R_OPEN_POL structure.
********************************************************************/
@ -446,6 +447,7 @@ char* lsa_io_r_sam_logoff(BOOL io, LSA_R_SAM_LOGOFF *r_l, char *q, char *base, i
return q;
}
#endif /* 0 LUKE PLEASE CHECK !! */
#if 0
/*******************************************************************
reads or writes a structure.

4
source/smbd/pipes.c
View File

@ -364,6 +364,8 @@ BOOL api_LsarpcTNP(int cnum,int uid, char *param,char *data,
return(True);
}
#if 0 /* HAVING TO DO THIS TO GET THINGS TO COMPILE - LUKE PLEASE CHECK THIS !!! */
/*
PAXX: Someone fix above.
The above API is indexing RPC calls based on RPC flags and
@ -757,3 +759,5 @@ static int lsa_reply_sam_logoff(LSA_Q_SAM_LOGOFF *q_s, char *q, char *base,
/* return length of SMB data stored */
return q - start;
}
#endif /* LUKE PLEASE CHECK THIS !! */

29
source/smbd/server.c
View File

@ -2455,6 +2455,9 @@ address %x. Error was %s\n", htonl(INADDR_LOOPBACK), strerror(errno)));
}
oplock_port = ntohs(sock_name.sin_port);
DEBUG(3,("open_oplock ipc: pid = %d, oplock_port = %u\n",
getpid(), oplock_port));
return True;
}
@ -2545,6 +2548,31 @@ pid %d, port %d, for file dev = %x, inode = %x\n", remotepid,
}
break;
/*
* Keep this as a debug case - eventually we can remove it.
*/
case 0x8001:
DEBUG(0,("process_local_message: Received unsolicited break \
reply - dumping info.\n"));
if(msg_len != OPLOCK_BREAK_MSG_LEN)
{
DEBUG(0,("process_local_message: ubr: incorrect length for reply \
(was %d, should be %d).\n", msg_len, OPLOCK_BREAK_MSG_LEN));
return False;
}
{
uint32 remotepid = IVAL(msg_start,OPLOCK_BREAK_PID_OFFSET);
uint32 dev = IVAL(msg_start,OPLOCK_BREAK_DEV_OFFSET);
uint32 inode = IVAL(msg_start, OPLOCK_BREAK_INODE_OFFSET);
DEBUG(0,("process_local_message: unsolicited oplock break reply from \
pid %d, port %d, dev = %x, inode = %x\n", remotepid, from_port, dev, inode));
}
return False;
default:
DEBUG(0,("process_local_message: unknown UDP message command code (%x) - ignoring.\n",
(unsigned int)SVAL(msg_start,0)));
@ -2860,6 +2888,7 @@ oplock break response from pid %d on port %d for dev = %x, inode = %x.\n",
share_entry->pid, share_entry->op_port, dev, inode));
if(push_local_message(op_break_reply, sizeof(op_break_reply)) == False)
return False;
continue;
}
break;

2
source/smbparse.c
View File

@ -456,7 +456,9 @@ char* smb_io_dom_query(BOOL io, DOM_QUERY *d_q, char *q, char *base, int align)
if (d_q->buffer_dom_name != 0)
{
#if 0 /* REMOVED AS WON'T COMPILE AS IS - LUKE PLEASE CHECK !!!!! */
q = smb_io_unistr(io, &(d_q->uni_domain_name), q, base, align); /* domain name (unicode string) */
#endif
}
if (d_q->buffer_dom_sid != 0)
{