4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Oscar Salvador <[email protected]>

commit 24962af7e1041b7e50c1bc71d8d10dc678c556b5 upstream.

The current code does not make sure to page align bss before calling
vm_brk(), and this can lead to a VM_BUG_ON() in __mm_populate() due to
the requested lenght not being correctly aligned.

Let us make sure to align it properly.

Kees: only applicable to CONFIG_USELIB kernels: 32-bit and configured
for libc5.

Link: 
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Oscar Salvador <[email protected]>
Reported-by: [email protected]
Tested-by: Tetsuo Handa <[email protected]>
Acked-by: Kees Cook <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Nicolas Pitre <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/binfmt_elf.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1235,9 +1235,8 @@ static int load_elf_library(struct file
                goto out_free_ph;
        }
 
-       len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
-                           ELF_MIN_ALIGN - 1);
-       bss = eppnt->p_memsz + eppnt->p_vaddr;
+       len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr);
+       bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr);
        if (bss > len) {
                error = vm_brk(len, bss - len);
                if (error)


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