From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: [PATCH] TTY: isdn: Replace strncpy with memcpy Date: Sun, 1 Jul 2018 13:57:38 -0700 Message-ID: <1530478658-23070-1-git-send-email-linux@roeck-us.net> Cc: Kees Cook , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Guenter Roeck To: Karsten Keil Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org gcc 8.1.0 complains: drivers/isdn/i4l/isdn_tty.c: In function 'isdn_tty_suspend.isra.1': drivers/isdn/i4l/isdn_tty.c:790:3: warning: 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length drivers/isdn/i4l/isdn_tty.c:778:6: note: length computed here drivers/isdn/i4l/isdn_tty.c: In function 'isdn_tty_resume': drivers/isdn/i4l/isdn_tty.c:880:3: warning: 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length drivers/isdn/i4l/isdn_tty.c:817:6: note: length computed here Using strncpy() is indeed less than perfect since the length of data to be copied has already been determined with strlen(). Replace strncpy() with memcpy() to address the warning and optimize the code a little. Signed-off-by: Guenter Roeck --- drivers/isdn/i4l/isdn_tty.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c index 960f26348bb5..b730037a0e2d 100644 --- a/drivers/isdn/i4l/isdn_tty.c +++ b/drivers/isdn/i4l/isdn_tty.c @@ -787,7 +787,7 @@ isdn_tty_suspend(char *id, modem_info *info, atemu *m) cmd.parm.cmsg.para[3] = 4; /* 16 bit 0x0004 Suspend */ cmd.parm.cmsg.para[4] = 0; cmd.parm.cmsg.para[5] = l; - strncpy(&cmd.parm.cmsg.para[6], id, l); + memcpy(&cmd.parm.cmsg.para[6], id, l); cmd.command = CAPI_PUT_MESSAGE; cmd.driver = info->isdn_driver; cmd.arg = info->isdn_channel; @@ -877,7 +877,7 @@ isdn_tty_resume(char *id, modem_info *info, atemu *m) cmd.parm.cmsg.para[3] = 5; /* 16 bit 0x0005 Resume */ cmd.parm.cmsg.para[4] = 0; cmd.parm.cmsg.para[5] = l; - strncpy(&cmd.parm.cmsg.para[6], id, l); + memcpy(&cmd.parm.cmsg.para[6], id, l); cmd.command = CAPI_PUT_MESSAGE; info->dialing = 1; // strcpy(dev->num[i], n); -- 2.7.4