From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Date: Wed, 26 Sep 2012 21:17:49 +0000 Subject: Re: [next:akpm 26/413] kernel/sys.c:1868:14: sparse: incorrect type in argument 1 (different base ty Message-Id: <20120926141749.e28247c8.akpm@linux-foundation.org> List-Id: References: <20120926155910.GA14447@localhost> In-Reply-To: <20120926155910.GA14447@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kernel-janitors@vger.kernel.org On Thu, 27 Sep 2012 00:06:38 +0300 Dan Carpenter wrote: > On Thu, Sep 27, 2012 at 12:19:34AM +0400, Cyrill Gorcunov wrote: > > On Wed, Sep 26, 2012 at 01:05:58PM -0700, Andrew Morton wrote: > > > > - if (!access_ok(VERIFY_READ, addr, sizeof(addr)) || addr < mmap_min_addr) > > > > + if (!access_ok(VERIFY_READ, (void *)addr, sizeof(addr)) || addr < mmap_min_addr) > > > > return -EINVAL; > > > > > > > > error = -EINVAL; > > > > > > It should have the __user tag as well, methinks? > > > > > > --- a/kernel/sys.c~prctl-use-access_ok-instead-of-task_size-in-prctl_set_mm-fix-fix > > > +++ a/kernel/sys.c > > > @@ -1865,7 +1865,8 @@ static int prctl_set_mm(int opt, unsigne > > > if (opt = PR_SET_MM_EXE_FILE) > > > return prctl_set_mm_exe_file(mm, (unsigned int)addr); > > > > > > - if (!access_ok(VERIFY_READ, (void *)addr, sizeof(addr)) || addr < mmap_min_addr) > > > + if (!access_ok(VERIFY_READ, (void __user *)addr, sizeof(addr)) || > > I would have expected sizeof(*addr) except addr is unsigned long. > To me sizeof(unsigned long) would be clearer. Well, we're setting a boundary here so what *is* the correct size? zero? maximum possible vm space? I think I'll drop the patch, pending some clear thinking ;)