From: kevans@FreeBSD.org
To: wireguard@lists.zx2c4.com
Cc: Kyle Evans <kevans@FreeBSD.org>
Subject: [PATCH 2/2] ipc: freebsd: NULL out some freed memory in kernel_set_device()
Date: Thu, 3 Nov 2022 13:38:21 -0500 [thread overview]
Message-ID: <20221103183821.48563-2-kevans@FreeBSD.org> (raw)
In-Reply-To: <20221103183821.48563-1-kevans@FreeBSD.org>
From: Kyle Evans <kevans@FreeBSD.org>
The `err` path in kernel_set_device() will attempt to free() allocated
nvl_peers, but these two cases meant we could end up attempting a use
after free or a double free, as we rely on nvlist_destroy(NULL) being
a NOP as well as free(NULL).
FreeBSD-Coverity: 1500421
Signed-off-by: Kyle Evans <kevans@FreeBSD.org>
---
src/ipc-freebsd.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/src/ipc-freebsd.h b/src/ipc-freebsd.h
index 78064e9..f9d3550 100644
--- a/src/ipc-freebsd.h
+++ b/src/ipc-freebsd.h
@@ -333,6 +333,7 @@ static int kernel_set_device(struct wgdevice *dev)
nvlist_destroy(nvl_aips[j]);
free(nvl_aips);
nvlist_destroy(nvl_peers[i]);
+ nvl_peers[i] = NULL;
goto err;
}
if (i) {
@@ -340,9 +341,11 @@ static int kernel_set_device(struct wgdevice *dev)
for (i = 0; i < peer_count; ++i)
nvlist_destroy(nvl_peers[i]);
free(nvl_peers);
+ nvl_peers = NULL;
}
wgd.wgd_data = nvlist_pack(nvl_device, &wgd.wgd_size);
nvlist_destroy(nvl_device);
+ nvl_device = NULL;
if (!wgd.wgd_data)
goto err;
s = get_dgram_socket();
--
2.36.1
prev parent reply other threads:[~2022-11-04 17:01 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-03 18:38 [PATCH 1/2] ipc: freebsd: avoid leaking memory in kernel_get_device() kevans
2022-11-03 18:38 ` kevans [this message]
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