[RFC PATCH] hw/s390x/sclp: Do not ignore address_space_read/write() errors

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

If address_space_read() fails, return PGM_ADDRESSING. In the
unlikely case address_space_write() fails (we already checked
the address is readable), return PGM_PROTECTION.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
Based-on: <20251007014958.19086-1-philmd@linaro.org>
---
 hw/s390x/sclp.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index d7cb99482b2..8604cd305e5 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -305,6 +305,7 @@ int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code)
     SCCBHeader header;
     g_autofree SCCB *work_sccb = NULL;
     AddressSpace *as = CPU(cpu)->as;
+    MemTxResult ret;
 
     /* first some basic checks on program checks */
     if (env->psw.mask & PSW_MASK_PSTATE) {
@@ -319,8 +320,11 @@ int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code)
     }
 
     /* the header contains the actual length of the sccb */
-    address_space_read(as, sccb, MEMTXATTRS_UNSPECIFIED,
-                       &header, sizeof(SCCBHeader));
+    ret = address_space_read(as, sccb, MEMTXATTRS_UNSPECIFIED,
+                             &header, sizeof(SCCBHeader));
+    if (ret != MEMTX_OK) {
+        return -PGM_ADDRESSING;
+    }
 
     /* Valid sccb sizes */
     if (be16_to_cpu(header.length) < sizeof(SCCBHeader)) {
@@ -333,8 +337,11 @@ int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code)
      * the host has checked the values
      */
     work_sccb = g_malloc0(be16_to_cpu(header.length));
-    address_space_read(as, sccb, MEMTXATTRS_UNSPECIFIED,
-                       work_sccb, be16_to_cpu(header.length));
+    ret = address_space_read(as, sccb, MEMTXATTRS_UNSPECIFIED,
+                             work_sccb, be16_to_cpu(header.length));
+    if (ret != MEMTX_OK) {
+        return -PGM_ADDRESSING;
+    }
 
     if (!sclp_command_code_valid(code)) {
         work_sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND);
@@ -348,8 +355,11 @@ int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code)
 
     sclp_c->execute(sclp, work_sccb, code);
 out_write:
-    address_space_write(as, sccb, MEMTXATTRS_UNSPECIFIED,
-                        work_sccb, be16_to_cpu(header.length));
+    ret = address_space_write(as, sccb, MEMTXATTRS_UNSPECIFIED,
+                              work_sccb, be16_to_cpu(header.length));
+    if (ret != MEMTX_OK) {
+        return -PGM_PROTECTION;
+    }
 
     sclp_c->service_interrupt(sclp, sccb);
 
-- 
2.51.0