The local variable 'pos' comes from userspace. If a large number was passed, there would be an integer overflow in the following line: pos += n; Signed-off-by: Wenliang Fan <fanwlexca@xxxxxxxxx> --- fs/nilfs2/ioctl.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c index b44bdb2..b2bac9a 100644 --- a/fs/nilfs2/ioctl.c +++ b/fs/nilfs2/ioctl.c @@ -90,8 +90,13 @@ static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs, total += nr; if ((size_t)nr < n) break; - if (pos == ppos) + if (pos == ppos) { + if (pos > ULONG_MAX - n) { + ret = -EINVAL; + break; + } pos += n; + } } argv->v_nmembs = total; -- 1.8.5.rc1.28.g7061504 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html