unofficial mirror of libc-alpha@sourceware.org
 help / color / mirror / Atom feed
From: Lukasz Majewski <lukma@denx.de>
To: Joseph Myers <joseph@codesourcery.com>, Paul Eggert <eggert@cs.ucla.edu>
Cc: Alistair Francis <alistair23@gmail.com>,
	Alistair Francis <alistair.francis@wdc.com>,
	GNU C Library <libc-alpha@sourceware.org>,
	Adhemerval Zanella <adhemerval.zanella@linaro.org>,
	Florian Weimer <fweimer@redhat.com>,
	Florian Weimer <fw@deneb.enyo.de>,
	Zack Weinberg <zackw@panix.com>,
	Carlos O'Donell <carlos@redhat.com>,
	Lukasz Majewski <lukma@denx.de>
Subject: [PATCH 2/2] linux: clock_settime: Return proper value when passing NULL pointer
Date: Fri,  8 Nov 2019 16:33:44 +0100	[thread overview]
Message-ID: <20191108153344.10949-2-lukma@denx.de> (raw)
In-Reply-To: <20191108153344.10949-1-lukma@denx.de>

When in __clock_settime function (__TIMESIZE != 64) the const struct
timespec's *tp pointer is NULL, the Linux kernel syscall returns
-EFAULT.
Without this patch the glibc crashes (when dereferencing NULL pointer)
as the Linux kernel syscall is not reached at all.

There is no need for such check in the __clock_settime64, as this
pointer either goes directly to Linux kernel or the pointer to local
copy is used (ts64).
---
 sysdeps/unix/sysv/linux/clock_settime.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/sysdeps/unix/sysv/linux/clock_settime.c b/sysdeps/unix/sysv/linux/clock_settime.c
index 6706dbb31f..e358a18998 100644
--- a/sysdeps/unix/sysv/linux/clock_settime.c
+++ b/sysdeps/unix/sysv/linux/clock_settime.c
@@ -51,7 +51,14 @@ __clock_settime64 (clockid_t clock_id, const struct __timespec64 *tp)
 int
 __clock_settime (clockid_t clock_id, const struct timespec *tp)
 {
-  struct __timespec64 ts64 = valid_timespec_to_timespec64 (*tp);
+  struct __timespec64 ts64;
+
+  if (tp == NULL)
+    {
+      __set_errno (EFAULT);
+      return -1;
+    }
+  ts64 = valid_timespec_to_timespec64 (*tp);
 
   return __clock_settime64 (clock_id, &ts64);
 }
-- 
2.20.1


  reply	other threads:[~2019-11-08 15:34 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-08 15:33 [PATCH 1/2] linux: clock_settime: Remove check for nanoseconds validity Lukasz Majewski
2019-11-08 15:33 ` Lukasz Majewski [this message]
2019-11-08 16:56   ` [PATCH 2/2] linux: clock_settime: Return proper value when passing NULL pointer Alistair Francis
2019-11-08 17:00     ` Joseph Myers
2019-11-08 16:20 ` [PATCH 1/2] linux: clock_settime: Remove check for nanoseconds validity Alistair Francis
2019-11-11 15:45 ` Lukasz Majewski
2019-11-27 17:04   ` Lukasz Majewski
2019-11-27 19:27     ` Paul Eggert

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.gnu.org/software/libc/involved.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191108153344.10949-2-lukma@denx.de \
    --to=lukma@denx.de \
    --cc=adhemerval.zanella@linaro.org \
    --cc=alistair.francis@wdc.com \
    --cc=alistair23@gmail.com \
    --cc=carlos@redhat.com \
    --cc=eggert@cs.ucla.edu \
    --cc=fw@deneb.enyo.de \
    --cc=fweimer@redhat.com \
    --cc=joseph@codesourcery.com \
    --cc=libc-alpha@sourceware.org \
    --cc=zackw@panix.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).