From ee3e84df78424d26fc6c90862fbe0fa92a686b0d Mon Sep 17 00:00:00 2001 From: Felix Abecassis Date: Tue, 21 Nov 2017 22:27:19 -0800 Subject: [PATCH] confile_utils: fix overlapping strncpy In the case of "lxc.net.0.type", the pointers passed to strncpy were only 2 elements apart, resulting in undefined behavior. Signed-off-by: Felix Abecassis --- src/lxc/confile_utils.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/src/lxc/confile_utils.c b/src/lxc/confile_utils.c index d86a2d88e..50f42ef8c 100644 --- a/src/lxc/confile_utils.c +++ b/src/lxc/confile_utils.c @@ -567,7 +567,8 @@ bool lxc_config_net_hwaddr(const char *line) return false; } /* strlen("hwaddr") = 6 */ - strncpy(copy + 8, p + 1, 6); + if (strlen(p + 1) >= 6) + memmove(copy + 8, p + 1, 6); copy[8 + 6] = '\0'; } if (strncmp(copy, "lxc.net.hwaddr", 14) == 0) { @@ -591,7 +592,8 @@ bool lxc_config_net_hwaddr(const char *line) return false; } /* strlen("hwaddr") = 6 */ - strncpy(copy + 12, p + 1, 6); + if (strlen(p + 1) >= 6) + memmove(copy + 12, p + 1, 6); copy[12 + 6] = '\0'; } if (strncmp(copy, "lxc.network.hwaddr", 18) == 0) { -- 2.47.2