From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50094) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dZi5i-0008Fz-7w for qemu-devel@nongnu.org; Mon, 24 Jul 2017 14:28:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dZi5f-0004kF-JC for qemu-devel@nongnu.org; Mon, 24 Jul 2017 14:28:26 -0400 Received: from mail-qk0-x241.google.com ([2607:f8b0:400d:c09::241]:37786) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1dZi5f-0004kB-F0 for qemu-devel@nongnu.org; Mon, 24 Jul 2017 14:28:23 -0400 Received: by mail-qk0-x241.google.com with SMTP id q130so10663079qka.4 for ; Mon, 24 Jul 2017 11:28:23 -0700 (PDT) Sender: =?UTF-8?Q?Philippe_Mathieu=2DDaud=C3=A9?= From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Mon, 24 Jul 2017 15:27:20 -0300 Message-Id: <20170724182751.18261-5-f4bug@amsat.org> In-Reply-To: <20170724182751.18261-1-f4bug@amsat.org> References: <20170724182751.18261-1-f4bug@amsat.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH for 2.10 04/35] ivshmem: fix incorrect error handling in ivshmem_recv_msg() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Paolo Bonzini , Markus Armbruster Cc: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , qemu-devel@nongnu.org If qemu_chr_fe_read_all() returns -EINTR the do {} statement continues and the n accumulator used to complete reads upto sizeof(msg) is decremented by 4 (the value of EINTR on Linux). To avoid that, use simpler if() statements and continue if EINTR occured. hw/misc/ivshmem.c:650:14: warning: Loss of sign in implicit conversion } while (n < sizeof(msg)); ^ Reported-by: Clang Static Analyzer Signed-off-by: Philippe Mathieu-Daudé --- get_maintainer.pl: No maintainers found! hw/misc/ivshmem.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index a58f9ee579..47a015f072 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -642,7 +642,10 @@ static int64_t ivshmem_recv_msg(IVShmemState *s, int *pfd, Error **errp) do { ret = qemu_chr_fe_read_all(&s->server_chr, (uint8_t *)&msg + n, sizeof(msg) - n); - if (ret < 0 && ret != -EINTR) { + if (ret < 0) { + if (ret == -EINTR) { + continue; + } error_setg_errno(errp, -ret, "read from server failed"); return INT64_MIN; } -- 2.13.3