| Message ID | 20230517113619.82808-1-frank@lichtenheld.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [Openvpn-devel,1/2,v4] buffer: use memcpy in buf_catrunc | expand |
Acked-by: Gert Doering <gert@greenie.muc.de> Change looks good (less +/-1, so easier for my old brain), and our nice and shiny new unit test confirms that things still work. Your patch has been applied to the master branch. commit c89a97e449baaf60924a362555d35184f188a646 Author: Frank Lichtenheld Date: Wed May 17 13:36:19 2023 +0200 buffer: use memcpy in buf_catrunc Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com> Acked-by: Gert Doering <gert@greenie.muc.de> Message-Id: <20230517113619.82808-1-frank@lichtenheld.com> URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg26683.html Signed-off-by: Gert Doering <gert@greenie.muc.de> -- kind regards, Gert Doering
diff --git a/src/openvpn/buffer.c b/src/openvpn/buffer.c index d099795b..7725438e 100644 --- a/src/openvpn/buffer.c +++ b/src/openvpn/buffer.c @@ -316,10 +316,10 @@ buf_catrunc(struct buffer *buf, const char *str) { if (buf_forward_capacity(buf) <= 1) { - int len = (int) strlen(str) + 1; + size_t len = strlen(str) + 1; if (len < buf_forward_capacity_total(buf)) { - strncpynt((char *)(buf->data + buf->capacity - len), str, len); + memcpy(buf->data + buf->capacity - len, str, len); } } }
Since we use strlen() to determine the length and then check it ourselves, there is really no point in using strncpy. But the compiler might complain that we use the output of strlen() for the length of strncpy which is usually a sign for bugs: error: ‘strncpy’ specified bound depends on the length of the source argument [-Werror=stringop-overflow=] Warning was at least triggered for mingw-gcc version 10-win32 20220113. Also change the type of len to size_t which avoids potential problems with signed overflow. v2: - make len size_t and change code to avoid any theoretical overflows - remove useless casts v3: - fix off-by-one introduced by v2 %) v4: - ignore unsigned overflow to simplify code Change-Id: If4a67adac4d2e870fd719b58075d39efcd67c671 Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com> --- src/openvpn/buffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)