From e529bfe8dee4bfde3ac74927b5b7b8df65cf3bb0 Mon Sep 17 00:00:00 2001
From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Wed, 7 May 2025 11:17:29 -0300
Subject: [PATCH] elf: Fix UB on _dl_map_object_from_fd

On 32-bit architecture ubsan triggers:

UBSAN: Undefined behaviour in dl-load.c:1345:54 pointer index expression with base 0x00612508 overflowed  to 0xf7c3a508

Use explicit uintptr_t operation instead.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
---
 elf/dl-load.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/elf/dl-load.c b/elf/dl-load.c
index bf29ec725d..6e26ef0583 100644
@@ -1359,7 +1359,7 @@ cannot enable executable stack as shared object requires");
 
   /* Adjust the address of the TLS initialization image.  */
   if (l->l_tls_initimage != NULL)
-    l->l_tls_initimage = (char *) l->l_tls_initimage + l->l_addr;
+    l->l_tls_initimage = (void*)((uintptr_t)l->l_tls_initimage + l->l_addr);
 
   /* Process program headers again after load segments are mapped in
      case processing requires accessing those segments.  Scan program
-- 
2.43.7