git: 5c18bf9d5fd7 - main - ktrace: Zero request structures when populating the pool

[Mark Johnston]

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=5c18bf9d5fd7684024e0a55da1e8537d4cfaf0bf

commit 5c18bf9d5fd7684024e0a55da1e8537d4cfaf0bf
Author:     Mark Johnston <markj at FreeBSD.org>
AuthorDate: 2021-07-23 14:29:53 +0000
Commit:     Mark Johnston <markj at FreeBSD.org>
CommitDate: 2021-07-23 14:29:53 +0000

    ktrace: Zero request structures when populating the pool
    
    Otherwise uninitialized pad bytes may be copied into the ktrace log
    file.
    
    Reported by:    KMSAN
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
---
 sys/kern/kern_ktrace.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sys/kern/kern_ktrace.c b/sys/kern/kern_ktrace.c
index 87cea3f269d5..be0ccfd344fa 100644
--- a/sys/kern/kern_ktrace.c
+++ b/sys/kern/kern_ktrace.c
@@ -219,7 +219,8 @@ ktrace_init(void *dummy)
 	sx_init(&ktrace_sx, "ktrace_sx");
 	STAILQ_INIT(&ktr_free);
 	for (i = 0; i < ktr_requestpool; i++) {
-		req = malloc(sizeof(struct ktr_request), M_KTRACE, M_WAITOK);
+		req = malloc(sizeof(struct ktr_request), M_KTRACE, M_WAITOK |
+		    M_ZERO);
 		STAILQ_INSERT_HEAD(&ktr_free, req, ktr_list);
 	}
 }
@@ -285,7 +286,7 @@ ktrace_resize_pool(u_int oldsize, u_int newsize)
 		STAILQ_INIT(&ktr_new);
 		while (bound-- > 0) {
 			req = malloc(sizeof(struct ktr_request), M_KTRACE,
-			    M_WAITOK);
+			    M_WAITOK | M_ZERO);
 			STAILQ_INSERT_HEAD(&ktr_new, req, ktr_list);
 		}
 		mtx_lock(&ktrace_mtx);