From: Mark Wielaard <mark@klomp.org>
Date: Fri, 11 Jul 2025 17:58:53 +0000 (+0200)
Subject: linux mseal PRE wrapper should First check for overflow
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;p=thirdparty%2Fvalgrind.git

linux mseal PRE wrapper should First check for overflow

According to https://docs.kernel.org/next/userspace-api/mseal.html
mseal returns -EINVAL when Address range (addr + len) overflow. The
LTP test mseal02 checks this. So do this check first before checking
for valid_client_addr (which returns -ENOMEM).
---

diff --git a/coregrind/m_syswrap/syswrap-linux.c b/coregrind/m_syswrap/syswrap-linux.c
index 51a47a16f..306c3a2f8 100644
--- a/coregrind/m_syswrap/syswrap-linux.c
+++ b/coregrind/m_syswrap/syswrap-linux.c
@@ -4315,7 +4315,10 @@ PRE(sys_mseal)
     /* int mseal(void *addr, size_t len, unsigned long flags) */
     PRINT("sys_mseal ( %#" FMT_REGWORD "x, %" FMT_REGWORD "u, %#" FMT_REGWORD "x, )", ARG1, ARG2, ARG3);
     PRE_REG_READ3(int, "mseal", void *, addr,  vki_size_t, len, int, flags);
-    if (!ML_(valid_client_addr)(ARG1, ARG2, tid, "mseal"))
+    /* First check for overflow which produces EINVAL.  */
+    if ((Addr)ARG1 > ((SizeT)(-1) - (SizeT)ARG2)) {
+       SET_STATUS_Failure(VKI_EINVAL);
+    } else if (!ML_(valid_client_addr)(ARG1, ARG2, tid, "mseal"))
        SET_STATUS_Failure(VKI_ENOMEM);
 }