diff options
| -rw-r--r-- | fs/nfs/direct.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 04ab2fc360e..4e9b3a1b36c 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -57,6 +57,7 @@ #define NFSDBG_FACILITY NFSDBG_VFS #define MAX_DIRECTIO_SIZE (4096UL << PAGE_SHIFT) +static void nfs_free_user_pages(struct page **pages, int npages, int do_dirty); static kmem_cache_t *nfs_direct_cachep; /* @@ -107,6 +108,15 @@ nfs_get_user_pages(int rw, unsigned long user_addr, size_t size, page_count, (rw == READ), 0, *pages, NULL); up_read(¤t->mm->mmap_sem); + /* + * If we got fewer pages than expected from get_user_pages(), + * the user buffer runs off the end of a mapping; return EFAULT. + */ + if (result >= 0 && result < page_count) { + nfs_free_user_pages(*pages, result, 0); + *pages = NULL; + result = -EFAULT; + } } return result; } |