[PATCH] spufs: Fix oops when spufs module is not loaded

try_module_get returns true when NULL arguments, so
we first need to check if there is a module loaded before
getting the reference count.

Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/arch/powerpc/platforms/cell/spu_syscalls.c b/arch/powerpc/platforms/cell/spu_syscalls.c
index 43e0b187ffde..91d564df944e 100644
--- a/arch/powerpc/platforms/cell/spu_syscalls.c
+++ b/arch/powerpc/platforms/cell/spu_syscalls.c
@@ -37,11 +37,12 @@ asmlinkage long sys_spu_create(const char __user *name,
                 unsigned int flags, mode_t mode)
 {
         long ret;
+        struct module *owner = spufs_calls.owner;
 
         ret = -ENOSYS;
-        if (try_module_get(spufs_calls.owner)) {
+        if (owner && try_module_get(spufs_calls.owner)) {
                 ret = spufs_calls.create_thread(name, flags, mode);
-                module_put(spufs_calls.owner);
+                module_put(owner);
         }
         return ret;
 }
@@ -51,16 +52,17 @@ asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
         long ret;
         struct file *filp;
         int fput_needed;
+        struct module *owner = spufs_calls.owner;
 
         ret = -ENOSYS;
-        if (try_module_get(spufs_calls.owner)) {
+        if (owner && try_module_get(owner)) {
                 ret = -EBADF;
                 filp = fget_light(fd, &fput_needed);
                 if (filp) {
                         ret = spufs_calls.spu_run(filp, unpc, ustatus);
                         fput_light(filp, fput_needed);
                 }
-                module_put(spufs_calls.owner);
+                module_put(owner);
         }
         return ret;
 }