mm/mprotect: fix do_mprotect_pkey() limit check

The return of do_mprotect_pkey() can still be incorrectly returned as
success if there is a gap that spans to or beyond the end address passed
in.  Update the check to ensure that the end address has indeed been seen.

Link: https://lore.kernel.org/all/CABi2SkXjN+5iFoBhxk71t3cmunTk-s=rB4T7qo0UQRh17s49PQ@mail.gmail.com/
Link: https://lkml.kernel.org/r/20230606182912.586576-1-Liam.Howlett@oracle.com
Fixes: 82f951340f25 ("mm/mprotect: fix do_mprotect_pkey() return on error")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Jeff Xu <jeffxu@chromium.org>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 92d3d3ca390a09de5f883d0b620608c3b4593aed..c59e7561698c8415ae783c100b3602c9fd03ac0f 100644 (file)
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -867,7 +867,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
        }
        tlb_finish_mmu(&tlb);
 
-       if (!error && vma_iter_end(&vmi) < end)
+       if (!error && tmp < end)
                error = -ENOMEM;
 
 out: