The branch stable/13 has been updated by brooks:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=9fcbd4c0d19cdbfa1fb4711c00c9c9cf84dbefb0

commit 9fcbd4c0d19cdbfa1fb4711c00c9c9cf84dbefb0
Author:     Brooks Davis <[email protected]>
AuthorDate: 2023-10-26 20:38:41 +0000
Commit:     Brooks Davis <[email protected]>
CommitDate: 2023-10-26 20:38:41 +0000

    libprocstat: simplify auxv value conversion
    
    Avoid a weird dance through the union and treat all 32-bit values as
    unsigned integers.  This avoids sign extension of flags and userspace
    pointers.
    
    Reviewed by:    markj
    Sponsored by:   DARPA
    Differential Revision:  https://reviews.freebsd.org/D42198
    
    (cherry picked from commit 9735cc0e41825bb9e95d16433d381ffe4c190f38)
---
 lib/libprocstat/libprocstat.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/lib/libprocstat/libprocstat.c b/lib/libprocstat/libprocstat.c
index d27c9f773151..0d7a0bcc2649 100644
--- a/lib/libprocstat/libprocstat.c
+++ b/lib/libprocstat/libprocstat.c
@@ -2417,7 +2417,6 @@ procstat_getauxv32_sysctl(pid_t pid, unsigned int *cntp)
 {
        Elf_Auxinfo *auxv;
        Elf32_Auxinfo *auxv32;
-       void *ptr;
        size_t len;
        unsigned int i, count;
        int name[4];
@@ -2451,8 +2450,17 @@ procstat_getauxv32_sysctl(pid_t pid, unsigned int *cntp)
                 * necessarily true.
                 */
                auxv[i].a_type = auxv32[i].a_type;
-               ptr = &auxv32[i].a_un;
-               auxv[i].a_un.a_val = *((uint32_t *)ptr);
+               /*
+                * Don't sign extend values.  Existing entries are positive
+                * integers or pointers.  Under freebsd32, programs typically
+                * have a full [0, 2^32) address space (perhaps minus the last
+                * page) and treating this as a signed integer would be
+                * confusing since these are not kernel pointers.
+                *
+                * XXX: A more complete translation would be ABI and
+                * type-aware.
+                */
+               auxv[i].a_un.a_val = (uint32_t)auxv32[i].a_un.a_val;
        }
        *cntp = count;
 out:

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