lockd: Don't expose the process pid to the NLM server

Instead we use the nlm_lockowner->pid.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

6 files changed, 34 insertions, 15 deletions

diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c
index da6354baa0b8..8ae79ae4b998 100644
--- a/fs/lockd/clntlock.c
+++ b/fs/lockd/clntlock.c
@@ -125,7 +125,15 @@ u32 nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *lock)
         list_for_each_entry(block, &nlm_blocked, b_list) {
                 struct file_lock *fl_blocked = block->b_lock;
 
-                if (!nlm_compare_locks(fl_blocked, fl))
+                if (fl_blocked->fl_start != fl->fl_start)
+                        continue;
+                if (fl_blocked->fl_end != fl->fl_end)
+                        continue;
+                /*
+                 * Careful! The NLM server will return the 32-bit "pid" that
+                 * we put on the wire: in this case the lockowner "pid".
+                 */
+                if (fl_blocked->fl_u.nfs_fl.owner->pid != lock->svid)
                         continue;
                 if (!nlm_cmp_addr(&block->b_host->h_addr, addr))
                         continue;
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 615a988a92a7..acc3eb13a02b 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -132,8 +132,10 @@ static void nlmclnt_setlockargs(struct nlm_rqst *req, struct file_lock *fl)
         memcpy(&lock->fh, NFS_FH(fl->fl_file->f_dentry->d_inode), sizeof(struct nfs_fh));
         lock->caller  = system_utsname.nodename;
         lock->oh.data = req->a_owner;
-        lock->oh.len  = sprintf(req->a_owner, "%d@%s",
-                                current->pid, system_utsname.nodename);
+        lock->oh.len  = snprintf(req->a_owner, sizeof(req->a_owner), "%u@%s",
+                                (unsigned int)fl->fl_u.nfs_fl.owner->pid,
+                                system_utsname.nodename);
+        lock->svid = fl->fl_u.nfs_fl.owner->pid;
         locks_copy_lock(&lock->fl, fl);
 }
 
@@ -159,6 +161,7 @@ nlmclnt_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock)
 
         /* set default data area */
         call->a_args.lock.oh.data = call->a_owner;
+        call->a_args.lock.svid = lock->fl.fl_pid;
 
         if (lock->oh.len > NLMCLNT_OHSIZE) {
                 void *data = kmalloc(lock->oh.len, GFP_KERNEL);
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 9cfced65d4a2..a525a141dd3b 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -397,6 +397,7 @@ nlmsvc_testlock(struct nlm_file *file, struct nlm_lock *lock,
                                 (long long)fl->fl_end);
                 conflock->caller = "somehost";  /* FIXME */
                 conflock->oh.len = 0;           /* don't return OH info */
+                conflock->svid = fl->fl_pid;
                 conflock->fl = *fl;
                 return nlm_lck_denied;
         }
diff --git a/fs/lockd/xdr.c b/fs/lockd/xdr.c
index 200fbda2c6d1..1e984ab14d3f 100644
--- a/fs/lockd/xdr.c
+++ b/fs/lockd/xdr.c
@@ -131,10 +131,11 @@ nlm_decode_lock(u32 *p, struct nlm_lock *lock)
          || !(p = nlm_decode_fh(p, &lock->fh))
          || !(p = nlm_decode_oh(p, &lock->oh)))
                 return NULL;
+        lock->svid  = ntohl(*p++);
 
         locks_init_lock(fl);
         fl->fl_owner = current->files;
-        fl->fl_pid   = ntohl(*p++);
+        fl->fl_pid   = (pid_t)lock->svid;
         fl->fl_flags = FL_POSIX;
         fl->fl_type  = F_RDLCK;         /* as good as anything else */
         start = ntohl(*p++);
@@ -174,7 +175,7 @@ nlm_encode_lock(u32 *p, struct nlm_lock *lock)
         else
                 len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
 
-        *p++ = htonl(fl->fl_pid);
+        *p++ = htonl(lock->svid);
         *p++ = htonl(start);
         *p++ = htonl(len);
 
@@ -197,7 +198,7 @@ nlm_encode_testres(u32 *p, struct nlm_res *resp)
                 struct file_lock        *fl = &resp->lock.fl;
 
                 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
-                *p++ = htonl(fl->fl_pid);
+                *p++ = htonl(resp->lock.svid);
 
                 /* Encode owner handle. */
                 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
@@ -298,7 +299,8 @@ nlmsvc_decode_shareargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
 
         memset(lock, 0, sizeof(*lock));
         locks_init_lock(&lock->fl);
-        lock->fl.fl_pid = ~(u32) 0;
+        lock->svid = ~(u32) 0;
+        lock->fl.fl_pid = (pid_t)lock->svid;
 
         if (!(p = nlm_decode_cookie(p, &argp->cookie))
          || !(p = xdr_decode_string_inplace(p, &lock->caller,
@@ -415,7 +417,8 @@ nlmclt_decode_testres(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
                 memset(&resp->lock, 0, sizeof(resp->lock));
                 locks_init_lock(fl);
                 excl = ntohl(*p++);
-                fl->fl_pid = ntohl(*p++);
+                resp->lock.svid = ntohl(*p++);
+                fl->fl_pid = (pid_t)resp->lock.svid;
                 if (!(p = nlm_decode_oh(p, &resp->lock.oh)))
                         return -EIO;
 
diff --git a/fs/lockd/xdr4.c b/fs/lockd/xdr4.c
index fdcf105a5303..906ddc203186 100644
--- a/fs/lockd/xdr4.c
+++ b/fs/lockd/xdr4.c
@@ -130,10 +130,11 @@ nlm4_decode_lock(u32 *p, struct nlm_lock *lock)
          || !(p = nlm4_decode_fh(p, &lock->fh))
          || !(p = nlm4_decode_oh(p, &lock->oh)))
                 return NULL;
+        lock->svid  = ntohl(*p++);
 
         locks_init_lock(fl);
         fl->fl_owner = current->files;
-        fl->fl_pid   = ntohl(*p++);
+        fl->fl_pid   = (pid_t)lock->svid;
         fl->fl_flags = FL_POSIX;
         fl->fl_type  = F_RDLCK;         /* as good as anything else */
         p = xdr_decode_hyper(p, &start);
@@ -167,7 +168,7 @@ nlm4_encode_lock(u32 *p, struct nlm_lock *lock)
          || (fl->fl_end > NLM4_OFFSET_MAX && fl->fl_end != OFFSET_MAX))
                 return NULL;
 
-        *p++ = htonl(fl->fl_pid);
+        *p++ = htonl(lock->svid);
 
         start = loff_t_to_s64(fl->fl_start);
         if (fl->fl_end == OFFSET_MAX)
@@ -198,7 +199,7 @@ nlm4_encode_testres(u32 *p, struct nlm_res *resp)
                 struct file_lock        *fl = &resp->lock.fl;
 
                 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
-                *p++ = htonl(fl->fl_pid);
+                *p++ = htonl(resp->lock.svid);
 
                 /* Encode owner handle. */
                 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
@@ -212,8 +213,8 @@ nlm4_encode_testres(u32 *p, struct nlm_res *resp)
                 
                 p = xdr_encode_hyper(p, start);
                 p = xdr_encode_hyper(p, len);
-                dprintk("xdr: encode_testres (status %d pid %d type %d start %Ld end %Ld)\n",
-                        resp->status, fl->fl_pid, fl->fl_type,
+                dprintk("xdr: encode_testres (status %u pid %d type %d start %Ld end %Ld)\n",
+                        resp->status, (int)resp->lock.svid, fl->fl_type,
                         (long long)fl->fl_start,  (long long)fl->fl_end);
         }
 
@@ -303,7 +304,8 @@ nlm4svc_decode_shareargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
 
         memset(lock, 0, sizeof(*lock));
         locks_init_lock(&lock->fl);
-        lock->fl.fl_pid = ~(u32) 0;
+        lock->svid = ~(u32) 0;
+        lock->fl.fl_pid = (pid_t)lock->svid;
 
         if (!(p = nlm4_decode_cookie(p, &argp->cookie))
          || !(p = xdr_decode_string_inplace(p, &lock->caller,
@@ -420,7 +422,8 @@ nlm4clt_decode_testres(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
                 memset(&resp->lock, 0, sizeof(resp->lock));
                 locks_init_lock(fl);
                 excl = ntohl(*p++);
-                fl->fl_pid = ntohl(*p++);
+                resp->lock.svid = ntohl(*p++);
+                fl->fl_pid = (pid_t)resp->lock.svid;
                 if (!(p = nlm4_decode_oh(p, &resp->lock.oh)))
                         return -EIO;
 
diff --git a/include/linux/lockd/xdr.h b/include/linux/lockd/xdr.h
index d7a5cc4cfa97..bb0a0f1caa91 100644
--- a/include/linux/lockd/xdr.h
+++ b/include/linux/lockd/xdr.h
@@ -28,6 +28,7 @@ struct nlm_lock {
         int                     len;    /* length of "caller" */
         struct nfs_fh           fh;
         struct xdr_netobj       oh;
+        u32                     svid;
         struct file_lock        fl;
 };