Fix 32-bit app crashing in 64-bit Android (v2)

Seemingly the 64-bit int is always aligned to 8 in LP64.
But this is not hold in LP32.

Consequently sizeof(gralloc_drm_handle_t) are different
between LP64 (which is 18 ints) and LP32 (which is 16 ints).
As a result, 32-bit apps will crash in 64-bit OS since the
checking handle->base.numInts != GRALLOC_GBM_HANDLE_NUM_INTS
is true.

Fix it by always aligning 64-bit int to 8. Besides, to avoid
additional padding, just exchange the order of data_owner
and modifier. It aligns modifier to 8 natually.
This makes gralloc_drm_handle_t fit in 16 ints perfectly.

(v2) gralloc_drm_handle.h patch now applied in gralloc_handle.h
     and GRALLOC_HANDLE_VERSION updated to 4

Reported-by: Mauro Rossi <issor.oruam@gmail.com>
Signed-off-by: Chih-Wei Huang <cwhuang@linux.org.tw>

diff --git a/android/gralloc_handle.h b/android/gralloc_handle.h
index bcf753d..d3d975e 100644 (file)
--- a/android/gralloc_handle.h
+++ b/android/gralloc_handle.h
@@ -60,16 +60,16 @@ struct gralloc_handle_t {
        uint32_t usage; /* android libhardware usage flags */
 
        uint32_t stride; /* the stride in bytes */
-       uint64_t modifier; /* buffer modifiers */
-
        int data_owner; /* owner of data (for validation) */
+       uint64_t modifier __attribute__((aligned(8))); /* buffer modifiers */
+
        union {
                void *data; /* pointer to struct gralloc_gbm_bo_t */
                uint64_t reserved;
        } __attribute__((aligned(8)));
 };
 
-#define GRALLOC_HANDLE_VERSION 3
+#define GRALLOC_HANDLE_VERSION 4
 #define GRALLOC_HANDLE_MAGIC 0x60585350
 #define GRALLOC_HANDLE_NUM_FDS 1
 #define GRALLOC_HANDLE_NUM_INTS (      \