From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oren Laadan Subject: Re: [PATCH 7/9] cr: checkpoint saved_auxv as u64s Date: Tue, 09 Feb 2010 15:43:18 -0500 Message-ID: <4B71C8E6.2010009@cs.columbia.edu> References: <1265680806-13295-1-git-send-email-serue@us.ibm.com> <1265680806-13295-8-git-send-email-serue@us.ibm.com> <4B71994E.10105@cs.columbia.edu> <20100209202035.GC29094@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100209202035.GC29094-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Serge E. Hallyn" Cc: containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org List-Id: containers.vger.kernel.org Serge E. Hallyn wrote: > Quoting Oren Laadan (orenl-eQaUEPhvms7ENvBUuze7eA@public.gmane.org): >> >> serue-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org wrote: >>> From: Serge E. Hallyn >>> >>> unsigned longs are not a good value to checkpoint between >>> x86-32 and x86-64 32-bit tasks :) >>> >>> Signed-off-by: Serge E. Hallyn >>> --- >>> checkpoint/checkpoint.c | 5 +-- >>> checkpoint/memory.c | 53 +++++++++++++++++++++++++++++++++++++-- >>> checkpoint/restart.c | 6 ++-- >>> include/linux/checkpoint_hdr.h | 2 +- >>> 4 files changed, 56 insertions(+), 10 deletions(-) >> [...] >> >> Sketch for a sanity check: >> >>> +static int ckpt_read_auxv(struct ckpt_ctx *ctx, struct mm_struct *mm) >>> +{ >>> + int i, ret; >>> + u64 *buf = kmalloc(CKPT_AT_SZ, GFP_KERNEL); >>> + >>> + if (!buf) >>> + return -ENOMEM; >>> + ret = _ckpt_read_buffer(ctx, buf, CKPT_AT_SZ); >>> + if (ret < 0) { >>> + kfree(buf); >>> + return ret; >>> + } >>> + >> ret = -E2BIG; >>> + for (i=0; i>> + if (buf[i] > (u64) ULONG_MAX) >> goto out; >> >> ret = -EINVAL; >> for (i=0; i> if (mm->saved_auxv[i] == AT_NULL) >> ret = 0; >> if (ret < 0) >> goto out; > > Yup, that would work. > > Alternatively, do you think it would be safe to just > always set the last entry to AT_NULL? A bit hacky, but should work. ... so I'll do just that :) Oren. > >>> + >>> + for (i=0; i>> + mm->saved_auxv[i] = buf[i]; >>> + >> out: >>> + kfree(buf); >>> + return 0; >> ret; >> >> [...] >> >> Oren. >