From: Richard Yao <richard.yao@alumni.stonybrook.edu>
Date: Mon, 5 Dec 2022 18:16:50 +0000 (-0500)
Subject: FreeBSD: zfs_register_callbacks() must implement error check correctly
X-Git-Tag: zfs-2.1.8~22
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=572114d8465bb928dec51b7668e6627df255b1d1;p=mirror_zfs.git

FreeBSD: zfs_register_callbacks() must implement error check correctly

I read the following article and noticed a couple of ZFS bugs mentioned:

https://pvs-studio.com/en/blog/posts/cpp/0377/

I decided to search for them in the modern OpenZFS codebase and then
found one that matched the description of the first one:

V593 Consider reviewing the expression of the 'A = B != C' kind. The
expression is calculated as following: 'A = (B != C)'. zfs_vfsops.c 498

The consequence of this is that the error value is replaced with `1`
when there is an error. When there is no error, 0 is correctly passed.
This is a very minor issue that is unlikely to cause any real problems.

The incorrect error code would either be returned to the mount command
on a failure or any of `zfs receive`, `zfs recv`, `zfs rollback` or `zfs
upgrade`.

The second one has already been fixed.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14261
---

diff --git a/module/os/freebsd/zfs/zfs_vfsops.c b/module/os/freebsd/zfs/zfs_vfsops.c
index 05d41d4e3..248b2d924 100644
--- a/module/os/freebsd/zfs/zfs_vfsops.c
+++ b/module/os/freebsd/zfs/zfs_vfsops.c
@@ -720,7 +720,7 @@ zfs_register_callbacks(vfs_t *vfsp)
 		nbmand = B_FALSE;
 	} else if (vfs_optionisset(vfsp, MNTOPT_NBMAND, NULL)) {
 		nbmand = B_TRUE;
-	} else if ((error = dsl_prop_get_int_ds(ds, "nbmand", &nbmand) != 0)) {
+	} else if ((error = dsl_prop_get_int_ds(ds, "nbmand", &nbmand)) != 0) {
 		dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
 		return (error);
 	}