Remove easily user-triggerable BUG from generic_setlease

This can be trivially triggered from userspace by passing in something unexpected.

    kernel BUG at fs/locks.c:1468!
    invalid opcode: 0000 [#1] SMP
    RIP: 0010:generic_setlease+0xc2/0x100
    Call Trace:
      __vfs_setlease+0x35/0x40
      fcntl_setlease+0x76/0x150
      sys_fcntl+0x1c6/0x810
      system_call_fastpath+0x1a/0x1f

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: stable@kernel.org # 3.2+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/locks.c b/fs/locks.c
index 814c51d0de4739e4b89e9091e00c17f284c0e2ba..fce6238d52c1bf742307325a588d545e169508e4 100644 (file)
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1465,7 +1465,7 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
        case F_WRLCK:
                return generic_add_lease(filp, arg, flp);
        default:
-               BUG();
+               return -EINVAL;
        }
 }
 EXPORT_SYMBOL(generic_setlease);