Re: [PATCH] VM/Security: add security hook to do_brk
On Tue, 4 Dec 2007, Alan Cox wrote: > On Tue, Dec 04, 2007 at 11:06:55AM -0500, Eric Paris wrote: > > Given a specifically crafted binary do_brk() can be used to get low > > pages available in userspace virtually memory and can thus be used to > > circumvent the mmap_min_addr low memory protection. Add security checks > > in do_brk(). > > > > Signed-off-by: Eric Paris <[EMAIL PROTECTED]> > > ACK Applied to git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6.git#for-akpm -- James Morris <[EMAIL PROTECTED]> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] VM/Security: add security hook to do_brk
On Tue, Dec 04, 2007 at 11:06:55AM -0500, Eric Paris wrote: > Given a specifically crafted binary do_brk() can be used to get low > pages available in userspace virtually memory and can thus be used to > circumvent the mmap_min_addr low memory protection. Add security checks > in do_brk(). > > Signed-off-by: Eric Paris <[EMAIL PROTECTED]> ACK -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH] VM/Security: add security hook to do_brk
Given a specifically crafted binary do_brk() can be used to get low pages available in userspace virtually memory and can thus be used to circumvent the mmap_min_addr low memory protection. Add security checks in do_brk(). Signed-off-by: Eric Paris <[EMAIL PROTECTED]> --- mm/mmap.c |4 1 file changed, 4 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index f4cfc6a..15678aa 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1941,6 +1941,10 @@ unsigned long do_brk(unsigned long addr, unsigned long len) if (is_hugepage_only_range(mm, addr, len)) return -EINVAL; + error = security_file_mmap(0, 0, 0, 0, addr, 1); + if (error) + return error; + flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags; error = arch_mmap_check(addr, len, flags); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
