s3: smbd: Use identical logic to test for kernel oplocks on a share.

Due to inconsistent use of lp_kernel_oplocks() we could miss kernel
oplocks being on/off in some of our oplock handling code, and thus
use the wrong logic.

Ensure all logic around koplocks and lp_kernel_oplocks() is consistent.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13193

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
Autobuild-User(master): Volker Lendecke <vl@samba.org>
Autobuild-Date(master): Thu Jan  4 16:03:38 CET 2018 on sn-devel-144

diff --git a/source3/smbd/oplock.c b/source3/smbd/oplock.c
index 1b2a87b8d8a98ab8e1eafc3189edf9e3f31af94e..e848b5e0d862cb1ae13418ca8b07d440d77a5726 100644 (file)
--- a/source3/smbd/oplock.c
+++ b/source3/smbd/oplock.c
@@ -56,7 +56,8 @@ NTSTATUS set_file_oplock(files_struct *fsp)
 {
        struct smbd_server_connection *sconn = fsp->conn->sconn;
        struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
-       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) && koplocks;
+       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
 
        if (fsp->oplock_type == LEVEL_II_OPLOCK) {
                if (use_kernel &&
@@ -98,7 +99,8 @@ static void release_file_oplock(files_struct *fsp)
 {
        struct smbd_server_connection *sconn = fsp->conn->sconn;
        struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
-       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) && koplocks;
+       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
 
        if ((fsp->oplock_type != NO_OPLOCK) &&
            use_kernel) {
@@ -131,13 +133,15 @@ static void downgrade_file_oplock(files_struct *fsp)
 {
        struct smbd_server_connection *sconn = fsp->conn->sconn;
        struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
+       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
 
        if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
                DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
                return;
        }
 
-       if (koplocks) {
+       if (use_kernel) {
                koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
        }
        fsp->oplock_type = LEVEL_II_OPLOCK;
@@ -729,12 +733,14 @@ static void add_oplock_timeout_handler(files_struct *fsp)
 {
        struct smbd_server_connection *sconn = fsp->conn->sconn;
        struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
+       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
 
        /*
         * If kernel oplocks already notifies smbds when an oplock break times
         * out, just return.
         */
-       if (koplocks &&
+       if (use_kernel &&
            (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
                return;
        }
@@ -845,7 +851,8 @@ static void process_oplock_break_message(struct messaging_context *msg_ctx,
                break_to &= ~SMB2_LEASE_READ;
        }
 
-       use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) && koplocks;
+       use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
        if (use_kernel && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) {
                DEBUG(10, ("Kernel oplocks don't allow level2\n"));
                break_to &= ~SMB2_LEASE_READ;
@@ -1255,8 +1262,10 @@ void smbd_contend_level2_oplocks_begin(files_struct *fsp,
 {
        struct smbd_server_connection *sconn = fsp->conn->sconn;
        struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
+       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
 
-       if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
+       if (use_kernel && koplocks->ops->contend_level2_oplocks_begin) {
                koplocks->ops->contend_level2_oplocks_begin(fsp, type);
                return;
        }
@@ -1269,9 +1278,11 @@ void smbd_contend_level2_oplocks_end(files_struct *fsp,
 {
        struct smbd_server_connection *sconn = fsp->conn->sconn;
        struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
+       bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
+                       (koplocks != NULL);
 
        /* Only kernel oplocks implement this so far */
-       if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
+       if (use_kernel && koplocks->ops->contend_level2_oplocks_end) {
                koplocks->ops->contend_level2_oplocks_end(fsp, type);
        }
 }