Add user poison functions (#494)

Author: b-sumner

amd/device-libs/asanrtl/src/shadow_mapping.cl

@@ -8,6 +8,7 @@
 #include "shadow_mapping.h"
 
 static const __constant u8 kAsanHeapLeftRedzoneMagic = (u8)0xfa;
+static const __constant u8 kAsanUserPoisonedMemoryMagic = (u8)0xf7;
 
 NO_SANITIZE_ADDR
 static uptr
@@ -69,3 +70,84 @@ __asan_poison_region(ulong beg, ulong size)
       __builtin_memset(shadow_ptr, kAsanHeapLeftRedzoneMagic, shadow_size);
     }
 }
+
+USED NO_SANITIZE_ADDR
+void
+__asan_poison_memory_region(const void *addr, uptr size)
+{
+    if (size == 0)
+        return;
+
+    uptr beg_addr = (uptr)addr;
+    uptr end_addr = beg_addr + size;
+
+    __global s8 *beg_sp = (__global s8 *)MEM_TO_SHADOW(beg_addr);
+    s8 beg_off = (s8)(beg_addr & (SHADOW_GRANULARITY - 1));
+    s8 beg_val = *beg_sp;
+
+    __global s8 *end_sp = (__global s8 *)MEM_TO_SHADOW(end_addr);
+    s8 end_off = (s8)(end_addr & (SHADOW_GRANULARITY - 1));
+    s8 end_val = *end_sp;
+
+    if (beg_sp == end_sp) {
+        s8 val = beg_val;
+        if (val > 0 && val <= end_off) {
+            if (beg_off > 0)
+                *beg_sp = (val < beg_off) ? val : beg_off;
+            else
+                *beg_sp = (s8)kAsanUserPoisonedMemoryMagic;
+        }
+        return;
+    }
+
+    if (beg_off > 0) {
+        if (beg_val == 0)
+            *beg_sp = beg_off;
+        else
+            *beg_sp = (beg_val < beg_off) ? beg_val : beg_off;
+        beg_sp++;
+    }
+
+    __builtin_memset(beg_sp, kAsanUserPoisonedMemoryMagic, end_sp - beg_sp);
+
+    if (end_val > 0 && end_val <= end_off)
+        *end_sp = (s8)kAsanUserPoisonedMemoryMagic;
+}
+
+USED NO_SANITIZE_ADDR
+void
+__asan_unpoison_memory_region(const void *addr, uptr size)
+{
+    if (size == 0)
+        return;
+
+    uptr beg_addr = (uptr)addr;
+    uptr end_addr = beg_addr + size;
+
+    __global s8 *beg_sp = (__global s8 *)MEM_TO_SHADOW(beg_addr);
+    s8 beg_off = (s8)(beg_addr & (SHADOW_GRANULARITY - 1));
+    s8 beg_val = *beg_sp;
+
+    __global s8 *end_sp = (__global s8 *)MEM_TO_SHADOW(end_addr);
+    s8 end_off = (s8)(end_addr & (SHADOW_GRANULARITY - 1));
+    s8 end_val = *end_sp;
+
+    if (beg_sp == end_sp) {
+        s8 val = beg_val;
+        if (val != 0)
+            *beg_sp = (val > end_off) ? val : end_off;
+        return;
+    }
+
+    __builtin_memset(beg_sp, 0, end_sp - beg_sp);
+
+    if (end_off > 0 && end_val != 0)
+        *end_sp = (end_val > end_off) ? end_val : end_off;
+}
+
+USED NO_SANITIZE_ADDR
+int
+__asan_address_is_poisoned(const void *addr)
+{
+    return is_address_poisoned((uptr)addr);
+}