[Valgrind-developers] [valgrind] FreeBSD client stack: add an assert to check the stringtable doesn't get overwritten

[Paul F. <pa...@so...>]

https://sourceware.org/cgit/valgrind/commit/?id=c48791a0db7ee5e69fd061c696608c121bb5b190

commit c48791a0db7ee5e69fd061c696608c121bb5b190
Author: Paul Floyd <pj...@wa...>
Date:   Sat Dec 6 10:50:38 2025 +0100

    FreeBSD client stack: add an assert to check the stringtable doesn't get overwritten
    
    There's already an assert that the stringsize calculated matches the
    stringsize writte. This adds a check that the pointer table area
    does not overwrite the stringtable (that is, that the NULL pointer after the
    last auxv entry pointer does not overwrite the first string [either the
    interpreter or argv[0])

Diff:
---
 coregrind/m_initimg/initimg-freebsd.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/coregrind/m_initimg/initimg-freebsd.c b/coregrind/m_initimg/initimg-freebsd.c
index cd127736ce..40f74168c9 100644
--- a/coregrind/m_initimg/initimg-freebsd.c
+++ b/coregrind/m_initimg/initimg-freebsd.c
@@ -841,6 +841,8 @@ static Addr setup_client_stack(const void*  init_sp,
 
    vg_assert((strtab-stringbase) == stringsize);
 
+   vg_assert((HChar*)auxv < stringbase);
+
    /* client_SP is pointing at client's argc/argv */
 
    if (0) {