From: Al Viro viro@zeniv.linux.org.uk
[ Upstream commit 7392ed1734c319150b5ddec3f192a6405728e8d0 ]
All callers can and should handle iov_iter_get_pages() returning fewer pages than requested. All in-kernel ones do. And it makes the arithmetical overflow analysis much simpler...
Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Sasha Levin sashal@kernel.org --- lib/iov_iter.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 6cf2d66fb839..ce24835abe55 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -1522,6 +1522,8 @@ ssize_t iov_iter_get_pages(struct iov_iter *i, maxsize = i->count; if (!maxsize) return 0; + if (maxsize > MAX_RW_COUNT) + maxsize = MAX_RW_COUNT;
if (likely(iter_is_iovec(i))) { unsigned int gup_flags = 0; @@ -1642,6 +1644,8 @@ ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, maxsize = i->count; if (!maxsize) return 0; + if (maxsize > MAX_RW_COUNT) + maxsize = MAX_RW_COUNT;
if (likely(iter_is_iovec(i))) { unsigned int gup_flags = 0;