1 files changed, 35 insertions, 16 deletions

diff --git a/linux-user/aarch64/signal.c b/linux-user/aarch64/signal.c
index 9ff79da4be..22d0b8b4ec 100644
--- a/linux-user/aarch64/signal.c
+++ b/linux-user/aarch64/signal.c
@@ -250,12 +250,36 @@ static void target_restore_fpsimd_record(CPUARMState *env,
     }
 }
 
-static void target_restore_sve_record(CPUARMState *env,
-                                      struct target_sve_context *sve, int vq)
+static bool target_restore_sve_record(CPUARMState *env,
+                                      struct target_sve_context *sve,
+                                      int size)
 {
-    int i, j;
+    int i, j, vl, vq;
 
-    /* Note that SVE regs are stored as a byte stream, with each byte element
+    if (!cpu_isar_feature(aa64_sve, env_archcpu(env))) {
+        return false;
+    }
+
+    __get_user(vl, &sve->vl);
+    vq = sve_vq(env);
+
+    /* Reject mismatched VL. */
+    if (vl != vq * TARGET_SVE_VQ_BYTES) {
+        return false;
+    }
+
+    /* Accept empty record -- used to clear PSTATE.SM. */
+    if (size <= sizeof(*sve)) {
+        return true;
+    }
+
+    /* Reject non-empty but incomplete record. */
+    if (size < TARGET_SVE_SIG_CONTEXT_SIZE(vq)) {
+        return false;
+    }
+
+    /*
+     * Note that SVE regs are stored as a byte stream, with each byte element
      * at a subsequent address.  This corresponds to a little-endian load
      * of our 64-bit hunks.
      */
@@ -277,6 +301,7 @@ static void target_restore_sve_record(CPUARMState *env,
             }
         }
     }
+    return true;
 }
 
 static int target_restore_sigframe(CPUARMState *env,
@@ -287,7 +312,7 @@ static int target_restore_sigframe(CPUARMState *env,
     struct target_sve_context *sve = NULL;
     uint64_t extra_datap = 0;
     bool used_extra = false;
-    int vq = 0, sve_size = 0;
+    int sve_size = 0;
 
     target_restore_general_frame(env, sf);
 
@@ -321,15 +346,9 @@ static int target_restore_sigframe(CPUARMState *env,
             if (sve || size < sizeof(struct target_sve_context)) {
                 goto err;
             }
-            if (cpu_isar_feature(aa64_sve, env_archcpu(env))) {
-                vq = sve_vq(env);
-                sve_size = QEMU_ALIGN_UP(TARGET_SVE_SIG_CONTEXT_SIZE(vq), 16);
-                if (size == sve_size) {
-                    sve = (struct target_sve_context *)ctx;
-                    break;
-                }
-            }
-            goto err;
+            sve = (struct target_sve_context *)ctx;
+            sve_size = size;
+            break;
 
         case TARGET_EXTRA_MAGIC:
             if (extra || size != sizeof(struct target_extra_context)) {
@@ -362,8 +381,8 @@ static int target_restore_sigframe(CPUARMState *env,
     }
 
     /* SVE data, if present, overwrites FPSIMD data.  */
-    if (sve) {
-        target_restore_sve_record(env, sve, vq);
+    if (sve && !target_restore_sve_record(env, sve, sve_size)) {
+        goto err;
     }
     unlock_user(extra, extra_datap, 0);
     return 0;