lockd: set file_lock start and end when decoding nlm4 testargs

Commit 6930bcbfb6ce dropped the setting of the file_lock range when
decoding a nlm_lock off the wire. This causes the client side grant
callback to miss matching blocks and reject the lock, only to rerequest
it 30s later.

Add a helper function to set the file_lock range from the start and end
values that the protocol uses, and have the nlm_lock decoder call that to
set up the file_lock args properly.

Fixes: 6930bcbfb6ce ("lockd: detect and reject lock arguments that overflow")
Reported-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Amir Goldstein <amir73il@gmail.com>
Cc: stable@vger.kernel.org #6.0
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/lockd/clnt4xdr.c b/fs/lockd/clnt4xdr.c
index 7df6324ccb8ab33ac9e04de7cbcfb11bb4eb1413..8161667c976f8c487de84ba9fcba189ae29072d9 100644 (file)
--- a/fs/lockd/clnt4xdr.c
+++ b/fs/lockd/clnt4xdr.c
@@ -261,7 +261,6 @@ static int decode_nlm4_holder(struct xdr_stream *xdr, struct nlm_res *result)
        u32 exclusive;
        int error;
        __be32 *p;
-       s32 end;
 
        memset(lock, 0, sizeof(*lock));
        locks_init_lock(fl);
@@ -285,13 +284,7 @@ static int decode_nlm4_holder(struct xdr_stream *xdr, struct nlm_res *result)
        fl->fl_type  = exclusive != 0 ? F_WRLCK : F_RDLCK;
        p = xdr_decode_hyper(p, &l_offset);
        xdr_decode_hyper(p, &l_len);
-       end = l_offset + l_len - 1;
-
-       fl->fl_start = (loff_t)l_offset;
-       if (l_len == 0 || end < 0)
-               fl->fl_end = OFFSET_MAX;
-       else
-               fl->fl_end = (loff_t)end;
+       nlm4svc_set_file_lock_range(fl, l_offset, l_len);
        error = 0;
 out:
        return error;

diff --git a/fs/lockd/xdr4.c b/fs/lockd/xdr4.c
index 712fdfeb8ef063bd1ad12f80c3c2ddf30f75101e..5fcbf30cd275928d1d364cf63e4f39fb61cb2a5a 100644 (file)
--- a/fs/lockd/xdr4.c
+++ b/fs/lockd/xdr4.c
@@ -33,6 +33,17 @@ loff_t_to_s64(loff_t offset)
        return res;
 }
 
+void nlm4svc_set_file_lock_range(struct file_lock *fl, u64 off, u64 len)
+{
+       s64 end = off + len - 1;
+
+       fl->fl_start = off;
+       if (len == 0 || end < 0)
+               fl->fl_end = OFFSET_MAX;
+       else
+               fl->fl_end = end;
+}
+
 /*
  * NLM file handles are defined by specification to be a variable-length
  * XDR opaque no longer than 1024 bytes. However, this implementation
@@ -80,7 +91,7 @@ svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock)
        locks_init_lock(fl);
        fl->fl_flags = FL_POSIX;
        fl->fl_type  = F_RDLCK;
-
+       nlm4svc_set_file_lock_range(fl, lock->lock_start, lock->lock_len);
        return true;
 }
 

diff --git a/include/linux/lockd/xdr4.h b/include/linux/lockd/xdr4.h
index 9a6b55da8fd6442c895267128a02ee02682971ed..72831e35dca32d7412d2705fd38b00ac029d5927 100644 (file)
--- a/include/linux/lockd/xdr4.h
+++ b/include/linux/lockd/xdr4.h
@@ -22,6 +22,7 @@
 #define        nlm4_fbig               cpu_to_be32(NLM_FBIG)
 #define        nlm4_failed             cpu_to_be32(NLM_FAILED)
 
+void   nlm4svc_set_file_lock_range(struct file_lock *fl, u64 off, u64 len);
 bool   nlm4svc_decode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr);
 bool   nlm4svc_decode_testargs(struct svc_rqst *rqstp, struct xdr_stream *xdr);
 bool   nlm4svc_decode_lockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr);