git: fa26f46dc29f - main - vn_lock_pair(): allow lkflags1/lkflags2 to be 0 if vp1/vp2 is NULL

The branch main has been updated by jah:

URL: https://cgit.FreeBSD.org/src/commit/?id=fa26f46dc29f5ee1ac8e7b10fc12aa1f93cce702

commit fa26f46dc29f5ee1ac8e7b10fc12aa1f93cce702
Author:     Jason A. Harmening <jah@FreeBSD.org>
AuthorDate: 2024-02-23 17:31:08 +0000
Commit:     Jason A. Harmening <jah@FreeBSD.org>
CommitDate: 2024-03-10 01:41:45 +0000

    vn_lock_pair(): allow lkflags1/lkflags2 to be 0 if vp1/vp2 is NULL
    
    It's a bit strange to require the caller to pass contrived lock flags
    if the corresponding vnode is NULL, simply to appease the assertion
    that exactly one of LK_SHARED or LK_EXCLUSIVE must be set.  On the
    other hand, we still want to catch cases in which completely bogus
    or corrupt flags are passed even if the corresponding vnode is NULL.
    Therefore, specifically allow empty flags for lkflags1/lkflags2 iff
    the respective vp1/vp2 param is NULL.
    
    Reviewed by:            kib, olce
    MFC after:              2 weeks
    Differential Revision:  https://reviews.freebsd.org/D44046
---
 sys/kern/vfs_vnops.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index 77e4dd21f276..fd78b692b088 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -4101,9 +4101,11 @@ vn_lock_pair(struct vnode *vp1, bool vp1_locked, int lkflags1,
 {
 	int error, locked1;
 
-	MPASS(((lkflags1 & LK_SHARED) != 0) ^ ((lkflags1 & LK_EXCLUSIVE) != 0));
+	MPASS((((lkflags1 & LK_SHARED) != 0) ^ ((lkflags1 & LK_EXCLUSIVE) != 0)) ||
+	    (vp1 == NULL && lkflags1 == 0));
 	MPASS((lkflags1 & ~(LK_SHARED | LK_EXCLUSIVE | LK_NODDLKTREAT)) == 0);
-	MPASS(((lkflags2 & LK_SHARED) != 0) ^ ((lkflags2 & LK_EXCLUSIVE) != 0));
+	MPASS((((lkflags2 & LK_SHARED) != 0) ^ ((lkflags2 & LK_EXCLUSIVE) != 0)) ||
+	    (vp2 == NULL && lkflags2 == 0));
 	MPASS((lkflags2 & ~(LK_SHARED | LK_EXCLUSIVE | LK_NODDLKTREAT)) == 0);
 
 	if (vp1 == NULL && vp2 == NULL)