git: 1babcad6bc40 - main - elf: Avoid dumping uninitialized bytes in PRSTATUS core dump notes

From: Mark Johnston <markj_at_FreeBSD.org>
Date: Wed, 23 Mar 2022 16:55:50 UTC
The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=1babcad6bc4093664a10c7ab98b9ebd2d64bcaaf

commit 1babcad6bc4093664a10c7ab98b9ebd2d64bcaaf
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2022-03-23 16:52:44 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2022-03-23 16:53:49 +0000

    elf: Avoid dumping uninitialized bytes in PRSTATUS core dump notes
    
    elf_prstatus_t contains pad space.
    
    Reported by:    KMSAN
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D34606
---
 sys/kern/imgact_elf.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 0f60835ce5e2..91c967c0c8de 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -2232,6 +2232,7 @@ __elfN(get_prstatus)(struct regset *rs, struct thread *td, void *buf,
 		KASSERT(*sizep == sizeof(*status), ("%s: invalid size",
 		    __func__));
 		status = buf;
+		memset(status, 0, *sizep);
 		status->pr_version = PRSTATUS_VERSION;
 		status->pr_statussz = sizeof(elf_prstatus_t);
 		status->pr_gregsetsz = sizeof(elf_gregset_t);