sockbuf: Add KMSAN checks to sbappend*()

Otherwise KMSAN only detects uninitialized memory when the contents of
the buffer are copied out to userspace or transmitted to a network
interface.  At that point the KMSAN violation will be far removed from
its origin, so let's try to make debugging such problems a bit easier.

Reviewed by:	glebius
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D38101
This commit is contained in:
Mark Johnston 2023-04-27 12:58:56 -04:00
parent 83fd35b3f3
commit ec45f952a2

View File

@ -44,6 +44,7 @@ __FBSDID("$FreeBSD$");
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/msan.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/protosw.h>
@ -908,6 +909,7 @@ sbappend_locked(struct sockbuf *sb, struct mbuf *m, int flags)
if (m == NULL)
return;
kmsan_check_mbuf(m, "sbappend");
sbm_clrprotoflags(m, flags);
SBLASTRECORDCHK(sb);
n = sb->sb_mb;
@ -1022,6 +1024,8 @@ sbappendstream_locked(struct sockbuf *sb, struct mbuf *m, int flags)
KASSERT(m->m_nextpkt == NULL,("sbappendstream 0"));
kmsan_check_mbuf(m, "sbappend");
#ifdef KERN_TLS
/*
* Decrypted TLS records are appended as records via
@ -1170,7 +1174,10 @@ sbappendrecord_locked(struct sockbuf *sb, struct mbuf *m0)
if (m0 == NULL)
return;
kmsan_check_mbuf(m0, "sbappend");
m_clrprotoflags(m0);
/*
* Put the first mbuf on the queue. Note this permits zero length
* records.
@ -1207,6 +1214,12 @@ sbappendaddr_locked_internal(struct sockbuf *sb, const struct sockaddr *asa,
struct mbuf *m0, struct mbuf *control, struct mbuf *ctrl_last)
{
struct mbuf *m, *n, *nlast;
if (m0 != NULL)
kmsan_check_mbuf(m0, "sbappend");
if (control != NULL)
kmsan_check_mbuf(control, "sbappend");
#if MSIZE <= 256
if (asa->sa_len > MLEN)
return (0);
@ -1317,6 +1330,9 @@ sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0,
{
struct mbuf *m, *mlast;
kmsan_check_mbuf(m0, "sbappend");
kmsan_check_mbuf(control, "sbappend");
sbm_clrprotoflags(m0, flags);
m_last(control)->m_next = m0;