Remove pid check in register/unregister
The register/unregister gralloc calls were avoiding
mmapping/munmapping the shared memory region if the buffer was created
by the current process. This is left over from the pmem-based
implementation, where trying to map the same region twice in the same
process would fail, or would reuse a single mapping without
refcounting.
This causes problems if a buffer is
- allocated in process A,
- transferred from A to process B and registered there
- unregistered/freed in A
- transferred back from B to A and re-registered
Process A then has a new handle to the buffer, but since it originally
created the buffer it will not be mmapped, so trying to read or write
the buffer will crash.
With ashmem, mmaping a region twice in the same process creates two
distinct mappings which can be used and munmapped independently. So
we no longer need to avoid mmapping again in the allocating process.
Bug: 8468756
Change-Id: I167bec5ca07e5534c5e2115630fe8386e481388e
diff --git a/modules/gralloc/gralloc_priv.h b/modules/gralloc/gralloc_priv.h
index e1c502a..9d14fe0 100644
--- a/modules/gralloc/gralloc_priv.h
+++ b/modules/gralloc/gralloc_priv.h
@@ -74,18 +74,16 @@
int size;
int offset;
- // FIXME: the attributes below should be out-of-line
+ // FIXME: this should be out-of-line
int base;
- int pid;
#ifdef __cplusplus
- static const int sNumInts = 6;
+ static const int sNumInts = 5;
static const int sNumFds = 1;
static const int sMagic = 0x3141592;
private_handle_t(int fd, int size, int flags) :
- fd(fd), magic(sMagic), flags(flags), size(size), offset(0),
- base(0), pid(getpid())
+ fd(fd), magic(sMagic), flags(flags), size(size), offset(0), base(0)
{
version = sizeof(native_handle);
numInts = sNumInts;