Cygwin: ps: fix compiler warning in ttynam

The helper function ttynam creates a tty name by using sprintf wrongly
on a pretty short buffer.  The foramt string only specifies a minimum
field length, not a maximum field length, so gcc-9.2.0 complains:

  ps.cc:101:23: warning: 'sprintf' may write a terminating nul past the
  end of the destination [-Wformat-overflow=]

Fix this thoroughly by specifying a maximum field width as well as by
using snprintf with a fixed buffer length.  Also, drop using a static
buffer in favor of using a buffer in the caller.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This commit is contained in:
Corinna Vinschen 2020-02-26 21:08:51 +01:00
parent 0a37e9f0bc
commit 09981903e6
1 changed files with 10 additions and 9 deletions

View File

@ -88,17 +88,17 @@ to_time_t (FILETIME *ptr)
}
static const char *
ttynam (int ntty)
ttynam (int ntty, char buf[9])
{
static char buf[9];
char buf0[9];
if (ntty < 0)
strcpy (buf0, "?");
else if (ntty & 0xffff0000)
sprintf (buf0, "cons%d", ntty & 0xff);
snprintf (buf0, 9, "cons%d", ntty & 0xff);
else
sprintf (buf0, "pty%d", ntty);
sprintf (buf, " %-7s", buf0);
snprintf (buf0, 9, "pty%d", ntty);
snprintf (buf, 9, " %-7.7s", buf0);
return buf;
}
@ -358,6 +358,7 @@ main (int argc, char *argv[])
}
char uname[128];
char ttyname[9];
if (fflag)
{
@ -373,13 +374,13 @@ main (int argc, char *argv[])
}
if (sflag)
printf (dfmt, p->pid, ttynam (p->ctty), start_time (p), pname);
printf (dfmt, p->pid, ttynam (p->ctty, ttyname), start_time (p), pname);
else if (fflag)
printf (ffmt, uname, p->pid, p->ppid, ttynam (p->ctty), start_time (p),
pname);
printf (ffmt, uname, p->pid, p->ppid, ttynam (p->ctty, ttyname),
start_time (p), pname);
else if (lflag)
printf (lfmt, status, p->pid, p->ppid, p->pgid,
p->dwProcessId, ttynam (p->ctty),
p->dwProcessId, ttynam (p->ctty, ttyname),
p->version >= EXTERNAL_PINFO_VERSION_32_BIT ? p->uid32 : p->uid,
start_time (p), pname);