diff options
| author | Eric Paris <eparis@redhat.com> | 2007-12-04 23:45:31 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-12-05 09:21:21 -0800 |
| commit | ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5 (patch) | |
| tree | cefce88c3d253992f939c2f8a1b66b8932272cbb | |
| parent | 294a80a8ed004b383ab214837e1c05ca4098a717 (diff) | |
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 virtual 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 <eparis@redhat.com>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/mmap.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index facc1a75bd4..acfc13f23ca 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1934,6 +1934,10 @@ 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); |