drivers/staging/intel_sst/intel_sst_app_interface.c: introduce missing kfree

Stream_bufs is initialized at the beginning of the function, and then the
#ifdef code declares a new variable with the same name and initializes
that.  If the if in the ifdef is taken, the then branch returns, implying
that the first stream_bufs is never used and is leaked.  The first
initialization is thus moved down after the ifdef.

The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/intel_sst/intel_sst_app_interface.c b/drivers/staging/intel_sst/intel_sst_app_interface.c
index 1d06212..d7454e2 100644 (file)
--- a/drivers/staging/intel_sst/intel_sst_app_interface.c
+++ b/drivers/staging/intel_sst/intel_sst_app_interface.c
@@ -418,10 +418,6 @@ static int snd_sst_fill_kernel_list(struct stream_info *stream,
        static int sent_offset;
        static unsigned long sent_index;
 
-       stream_bufs = kzalloc(sizeof(*stream_bufs), GFP_KERNEL);
-       if (!stream_bufs)
-               return -ENOMEM;
-       stream_bufs->addr = sst_drv_ctx->mmap_mem;
 #ifdef CONFIG_MRST_RAR_HANDLER
        if (stream->ops == STREAM_OPS_PLAYBACK_DRM) {
                for (index = stream->sg_index; index < nr_segs; index++) {
@@ -448,6 +444,10 @@ static int snd_sst_fill_kernel_list(struct stream_info *stream,
                return retval;
        }
 #endif
+       stream_bufs = kzalloc(sizeof(*stream_bufs), GFP_KERNEL);
+       if (!stream_bufs)
+               return -ENOMEM;
+       stream_bufs->addr = sst_drv_ctx->mmap_mem;
        mmap_len = sst_drv_ctx->mmap_len;
        stream_bufs->addr = sst_drv_ctx->mmap_mem;
        bufp = stream->cur_ptr;