[PATCH 3.19 025/175] ASoC: Intel: sst: Fix firmware name size handling

Greg Kroah-Hartman
2015-03-04T07:06:16Z

From: Christian Engelmayer <cengelma@gmx.at>

commit 279e17ae81c17b40ae7a6c9e10f386a7aac7aa55 upstream.

Function sst_acpi_probe() uses plain strcpy for setting member firmware_name
of a struct intel_sst_drv from member firmware of a struct sst_machines.
Thereby the destination array has got a length of 20 byte while the source may
hold 32 byte. Since eg. commit 64b9c90b8600 ("ASoC: Intel: Fix BYTCR firmware
name") increased strings from "fw_sst_0f28.bin" to "intel/fw_sst_0f28.bin"
there is an actual possibility that the 20 byte array at the end of struct
intel_sst_drv is overrun.

Thus increase the size of the destination and use the same define for both
structs. Detected by Coverity CID 1260087.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/soc/intel/sst/sst.h | 3 ++-
sound/soc/intel/sst/sst_acpi.c | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)

--- a/sound/soc/intel/sst/sst.h
+++ b/sound/soc/intel/sst/sst.h
@@ -58,6 +58,7 @@ enum sst_algo_ops {
#define SST_BLOCK_TIMEOUT 1000

#define FW_SIGNATURE_SIZE 4
+#define FW_NAME_SIZE 32

/* stream states */
enum sst_stream_states {
@@ -426,7 +427,7 @@ struct intel_sst_drv {
* Holder for firmware name. Due to async call it needs to be
* persistent till worker thread gets called
*/
- char firmware_name[20];
+ char firmware_name[FW_NAME_SIZE];
};

/* misc definitions */
--- a/sound/soc/intel/sst/sst_acpi.c
+++ b/sound/soc/intel/sst/sst_acpi.c
@@ -47,7 +47,7 @@ struct sst_machines {
char board[32];
char machine[32];
void (*machine_quirk)(void);
- char firmware[32];
+ char firmware[FW_NAME_SIZE];
struct sst_platform_info *pdata;

};