[PATCH 63/71] linux-user/aarch64: Do not allow duplicate or short sve records

[Richard Henderson <richard.henderson@linaro.org>]

In parse_user_sigframe, the kernel rejects duplicate sve records,
or records that are smaller than the header.  We were silently
allowing these cases to pass, dropping the record.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/aarch64/signal.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/linux-user/aarch64/signal.c b/linux-user/aarch64/signal.c
index e9ff280d2a..590f2258b2 100644
--- a/linux-user/aarch64/signal.c
+++ b/linux-user/aarch64/signal.c
@@ -318,10 +318,13 @@ static int target_restore_sigframe(CPUARMState *env,
             break;
 
         case TARGET_SVE_MAGIC:
+            if (sve || size < sizeof(struct target_sve_context)) {
+                goto err;
+            }
             if (cpu_isar_feature(aa64_sve, env_archcpu(env))) {
                 vq = sve_vq_cached(env);
                 sve_size = QEMU_ALIGN_UP(TARGET_SVE_SIG_CONTEXT_SIZE(vq), 16);
-                if (!sve && size == sve_size) {
+                if (size == sve_size) {
                     sve = (struct target_sve_context *)ctx;
                     break;
                 }
-- 
2.34.1