summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorSimon Howard2015-02-22 00:28:23 -0500
committerSimon Howard2015-02-22 00:28:23 -0500
commit01a743cd351d146e9b9ea7f7ca5b1c05e01da68e (patch)
tree122dbb74806badb164f6bd780334780bbc7b0595
parentb39121c6a682eb8ae5efd29a875bd7c098185f04 (diff)
downloadchocolate-doom-01a743cd351d146e9b9ea7f7ca5b1c05e01da68e.tar.gz
chocolate-doom-01a743cd351d146e9b9ea7f7ca5b1c05e01da68e.tar.bz2
chocolate-doom-01a743cd351d146e9b9ea7f7ca5b1c05e01da68e.zip
Fix mistaken uses of memcpy() on overlapping memory.
The source and destination arguments to memcpy() cannot be overlapping as this is undefined behavior. In these situations memmove() must be used instead, and OpenBSD actually throws an error if this is done. Thanks to ryan-sg for reporting this. This fixes #510.
-rw-r--r--src/net_client.c4
-rw-r--r--src/net_server.c3
-rw-r--r--src/net_structrw.c2
-rw-r--r--textscreen/txt_io.c4
4 files changed, 7 insertions, 6 deletions
diff --git a/src/net_client.c b/src/net_client.c
index e0037e3e..ac81e367 100644
--- a/src/net_client.c
+++ b/src/net_client.c
@@ -279,8 +279,8 @@ static void NET_CL_AdvanceWindow(void)
// Advance the window
- memcpy(recvwindow, recvwindow + 1,
- sizeof(net_server_recv_t) * (BACKUPTICS - 1));
+ memmove(recvwindow, recvwindow + 1,
+ sizeof(net_server_recv_t) * (BACKUPTICS - 1));
memset(&recvwindow[BACKUPTICS-1], 0, sizeof(net_server_recv_t));
++recvwindow_start;
diff --git a/src/net_server.c b/src/net_server.c
index b4496bb5..b3ec1693 100644
--- a/src/net_server.c
+++ b/src/net_server.c
@@ -514,7 +514,8 @@ static void NET_SV_AdvanceWindow(void)
// Advance the window
- memcpy(recvwindow, recvwindow + 1, sizeof(*recvwindow) * (BACKUPTICS - 1));
+ memmove(recvwindow, recvwindow + 1,
+ sizeof(*recvwindow) * (BACKUPTICS - 1));
memset(&recvwindow[BACKUPTICS-1], 0, sizeof(*recvwindow));
++recvwindow_start;
diff --git a/src/net_structrw.c b/src/net_structrw.c
index 60316dc7..a820df5f 100644
--- a/src/net_structrw.c
+++ b/src/net_structrw.c
@@ -316,7 +316,7 @@ void NET_TiccmdDiff(ticcmd_t *tic1, ticcmd_t *tic2, net_ticdiff_t *diff)
void NET_TiccmdPatch(ticcmd_t *src, net_ticdiff_t *diff, ticcmd_t *dest)
{
- memcpy(dest, src, sizeof(ticcmd_t));
+ memmove(dest, src, sizeof(ticcmd_t));
// Apply the diff
diff --git a/textscreen/txt_io.c b/textscreen/txt_io.c
index ed25503c..0c5e274f 100644
--- a/textscreen/txt_io.c
+++ b/textscreen/txt_io.c
@@ -39,8 +39,8 @@ static void NewLine(unsigned char *screendata)
cur_y = TXT_SCREEN_H - 1;
- memcpy(screendata, screendata + TXT_SCREEN_W * 2,
- TXT_SCREEN_W * 2 * (TXT_SCREEN_H -1));
+ memmove(screendata, screendata + TXT_SCREEN_W * 2,
+ TXT_SCREEN_W * 2 * (TXT_SCREEN_H -1));
// Clear the bottom line