rocr: fix nullptr dereference (#262)

* rocr: fix nullptr dereference

Return early in the case that malloc fails to avoid dereferencing of a
null pointer on eventDescrp.

Signed-off-by: Sunday Clement <Sunday.Clement@amd.com>

* rocr: Fix potential nullptr dereference

returns early if sym->section() fails to properly acquire the object.

Signed-off-by: Sunday Clement <Sunday.Clement@amd.com>

---------

Signed-off-by: Sunday Clement <Sunday.Clement@amd.com>
Co-authored-by: Sunday Clement <Sunday.Clement@amd.com>

projects/rocr-runtime/runtime/hsa-runtime/core/util/lnx/os_linux.cpp

@@ -540,6 +540,8 @@ EventHandle CreateOsEvent(bool auto_reset, bool init_state) {
   EventDescriptor* eventDescrp;
   eventDescrp = (EventDescriptor*)malloc(sizeof(EventDescriptor));
   
+  if(!eventDescrp) { return nullptr; }
+
   pthread_mutex_init(&eventDescrp->mutex, NULL);
   pthread_cond_init(&eventDescrp->event, NULL);
   eventDescrp->auto_reset = auto_reset;

projects/rocr-runtime/runtime/hsa-runtime/loader/executable.cpp

@@ -1614,6 +1614,8 @@ uint64_t ExecutableImpl::SymbolAddress(hsa_agent_t agent, code::Symbol* sym)
 uint64_t ExecutableImpl::SymbolAddress(hsa_agent_t agent, elf::Symbol* sym)
 {
   elf::Section* sec = sym->section();
+  if(!sec) { return NULL; }
+  
   Segment* seg = SectionSegment(agent, sec);
   uint64_t vaddr = sec->addr() + sym->value();
   return nullptr == seg ? 0 : (uint64_t) (uintptr_t) seg->Address(vaddr);