[PATCH] libdwfl: linux-pid-attach.c: Report actual PID (Tgid) to dwfl_attach_state.
Mark Wielaard
mjw at redhat.com
Thu Jan 2 22:15:03 UTC 2014
On Thu, Jan 02, 2014 at 04:24:04PM +0100, Jan Kratochvil wrote:
> On Wed, 25 Dec 2013 23:10:50 +0100, Mark Wielaard wrote:
> > It would be zero in the very unlikely case atoi doesn't see any digits.
>
> If you want to check /proc files validity there should be strtol and not
> atoi.
> "Tgid: 42foo\n" still gets parsed as 42 by the code above.
OK, it is somewhat unlikely that the /proc file would be that garbled,
but with strtol we can at least detect it.
Thanks,
Mark
-------------- next part --------------
>From 68de442d13f7b3192d0b81634c0f2136002c4552 Mon Sep 17 00:00:00 2001
From: Mark Wielaard <mjw at redhat.com>
Date: Thu, 2 Jan 2014 21:17:18 +0100
Subject: [PATCH] libdwfl: linux-pid-attach.c (dwfl_linux_proc_attach): Use and
check strtol
Signed-off-by: Mark Wielaard <mjw at redhat.com>
---
libdwfl/ChangeLog | 4 ++++
libdwfl/linux-pid-attach.c | 11 +++++++++--
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index 2190899..766fb18 100644
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,7 @@
+2014-01-02 Mark Wielaard <mjw at redhat.com>
+
+ * linux-pid-attach.c (dwfl_linux_proc_attach): Use strtol, not atoi.
+
2013-12-30 Mark Wielaard <mjw at redhat.com>
* argp-std.c (parse_opt): Call dwfl_linux_proc_attach and
diff --git a/libdwfl/linux-pid-attach.c b/libdwfl/linux-pid-attach.c
index 21ff4b9..58d6942 100644
--- a/libdwfl/linux-pid-attach.c
+++ b/libdwfl/linux-pid-attach.c
@@ -306,8 +306,15 @@ dwfl_linux_proc_attach (Dwfl *dwfl, pid_t pid, bool assume_ptrace_stopped)
while (getline (&line, &linelen, procfile) >= 0)
if (strncmp (line, "Tgid:", 5) == 0)
{
- pid = atoi (&line[5]);
- break;
+ errno = 0;
+ char *endptr;
+ long val = strtol (&line[5], &endptr, 10);
+ if ((errno == ERANGE && val == LONG_MAX)
+ || *endptr != '\n' || val < 0 || val != (pid_t) val)
+ pid = 0;
+ else
+ pid = (pid_t) val;
+ break;
}
free (line);
fclose (procfile);
--
1.8.4.2
More information about the elfutils-devel
mailing list