From 2c80929c4c4d54e568b07ab85877d5fd38f4b02f Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 24 Sep 2014 17:09:11 +0200 Subject: fuse: honour max_read and max_write in direct_io mode The third argument of fuse_get_user_pages() "nbytesp" refers to the number of bytes a caller asked to pack into fuse request. This value may be lesser than capacity of fuse request or iov_iter. So fuse_get_user_pages() must ensure that *nbytesp won't grow. Now, when helper iov_iter_get_pages() performs all hard work of extracting pages from iov_iter, it can be done by passing properly calculated "maxsize" to the helper. The other caller of iov_iter_get_pages() (dio_refill_pages()) doesn't need this capability, so pass LONG_MAX as the maxsize argument here. Fixes: c9c37e2e6378 ("fuse: switch to iov_iter_get_pages()") Reported-by: Werner Baumann Tested-by: Maxim Patlasov Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro --- fs/direct-io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/direct-io.c') diff --git a/fs/direct-io.c b/fs/direct-io.c index c311640..e181b6b 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -158,7 +158,7 @@ static inline int dio_refill_pages(struct dio *dio, struct dio_submit *sdio) { ssize_t ret; - ret = iov_iter_get_pages(sdio->iter, dio->pages, DIO_PAGES, + ret = iov_iter_get_pages(sdio->iter, dio->pages, LONG_MAX, DIO_PAGES, &sdio->from); if (ret < 0 && sdio->blocks_available && (dio->rw & WRITE)) { -- cgit v1.1