Hi!
As mentioned in the PR, strncat does something different from what the
code expects (the last argument is the maximum number of characters
to be copied, rather than maximum number of characters in the destination
buffer). As for the (highly unlikely, because d->d_name really should be
the pid numbers plus a couple of extra dirnames) case of truncated name
trying to open such truncated filename wouldn't work anyway, this
patch just skips it altogether if there would be overflow.
GCC strlen pass should be able to optimize all the 3 calls into memcpy,
using strlen value from the earlier strlen call.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2017-02-01 Jakub Jelinek <ja...@redhat.com>
PR ada/79309
* adaint.c (__gnat_killprocesstree): Don't clear statfile
before overwriting it. If d->d_name is too long, skip trying
to construct the filename and open it. Use strcpy/strcat
instead of strncpy/strncat.
--- gcc/ada/adaint.c.jj 2017-01-12 22:28:59.293871830 +0100
+++ gcc/ada/adaint.c 2017-02-01 09:18:47.027598963 +0100
@@ -3396,14 +3396,16 @@ void __gnat_killprocesstree (int pid, in
{
if ((d->d_type & DT_DIR) == DT_DIR)
{
- char statfile[64] = { 0 };
+ char statfile[64];
int _pid, _ppid;
/* read /proc/<PID>/stat */
- strncpy (statfile, "/proc/", sizeof(statfile));
- strncat (statfile, d->d_name, sizeof(statfile));
- strncat (statfile, "/stat", sizeof(statfile));
+ if (strlen (d->d_name) > sizeof (statfile) - sizeof ("/proc//stat"))
+ continue;
+ strcpy (statfile, "/proc/");
+ strcat (statfile, d->d_name);
+ strcat (statfile, "/stat");
FILE *fd = fopen (statfile, "r");
Jakub
