ceph: strengthen rsize/wsize/readdir_max_bytes validation

The check (intval < PAGE_SIZE) will involve type cast, so even when
specifying negative value to rsize/wsize/readdir_max_bytes, it will
pass the validation check successfully.

Signed-off-by: Chengguang Xu <[email protected]>
Reviewed-by: Ilya Dryomov <[email protected]>
Signed-off-by: Ilya Dryomov <[email protected]>

diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index b4ff1392e33399d7904ddc1f52e1f2ecfe707a18..cec1d3343742d3725cd12c49f29810f0555bcb9b 100644 (file)
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -259,12 +259,12 @@ static int parse_fsopt_token(char *c, void *private)
                break;
                /* misc */
        case Opt_wsize:
-               if (intval < PAGE_SIZE || intval > CEPH_MAX_WRITE_SIZE)
+               if (intval < (int)PAGE_SIZE || intval > CEPH_MAX_WRITE_SIZE)
                        return -EINVAL;
                fsopt->wsize = ALIGN(intval, PAGE_SIZE);
                break;
        case Opt_rsize:
-               if (intval < PAGE_SIZE || intval > CEPH_MAX_READ_SIZE)
+               if (intval < (int)PAGE_SIZE || intval > CEPH_MAX_READ_SIZE)
                        return -EINVAL;
                fsopt->rsize = ALIGN(intval, PAGE_SIZE);
                break;
@@ -289,7 +289,7 @@ static int parse_fsopt_token(char *c, void *private)
                fsopt->max_readdir = intval;
                break;
        case Opt_readdir_max_bytes:
-               if (intval < PAGE_SIZE && intval != 0)
+               if (intval < (int)PAGE_SIZE && intval != 0)
                        return -EINVAL;
                fsopt->max_readdir_bytes = intval;
                break;