[lxc-devel] [lxd/master] seccomp: check the return value of pwrite()

[brauner on Github]

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From 77544a6133846fe5e7da54e8f7ef89201c75cbb1 Mon Sep 17 00:00:00 2001
From: Christian Brauner <christian.brauner at ubuntu.com>
Date: Sun, 9 Aug 2020 08:55:57 +0200
Subject: [PATCH] seccomp: check the return value of pwrite()

Link: https://launchpadlibrarian.net/492514639/buildlog_snap_ubuntu_bionic_amd64_lxd-latest-edge_BUILDING.txt.gz
Signed-off-by: Christian Brauner <christian.brauner at ubuntu.com>
---
 lxd/seccomp/seccomp.go | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lxd/seccomp/seccomp.go b/lxd/seccomp/seccomp.go
index 7c87c07e94..459728cd05 100644
--- a/lxd/seccomp/seccomp.go
+++ b/lxd/seccomp/seccomp.go
@@ -361,9 +361,8 @@ static int handle_bpf_syscall(int notify_fd, int mem_fd, struct seccomp_notify_p
 		bpf_prog_fd = bpf(cmd, &new_attr, sizeof(new_attr));
 		if (bpf_prog_fd < 0) {
 			int saved_errno = errno;
-			if (log_buf)
-				pwrite(mem_fd, log_buf, attr.log_size, attr.log_buf);
-			errno = saved_errno;
+			if (log_buf && pwrite(mem_fd, log_buf, attr.log_size, attr.log_buf) < 0)
+				errno = saved_errno;
 			return -errno;
 		}