From 37c5b64e0e6966afe66d62ad9c700d27f3065e4e Mon Sep 17 00:00:00 2001

From: Dmitry Safonov <dima@arista.com>

Date: Thu, 10 May 2018 19:14:43 +0100

Subject: [PATCH 3/8] aio: Allow expressions in NR_IOEVENTS_IN_PAGES macro

The macro is used only in aio_estimate_nr_reqs():

unsigned int k_max_reqs = NR_IOEVENTS_IN_NPAGES(size/PAGE_SIZE);

Which compiler may evaluate as (((PAGE_SIZE*size)/PAGE_SIZE) - ...)

It works as long as PAGE_SIZE is long.

The patches set converts PAGE_SIZE to use sysconf() returning

(unsigned), non-long type and making the aio macro overflowing.

I do not see any value making PAGE_SIZE (unsigned long) typed.

Cc: Kirill Tkhai <ktkhai@virtuozzo.com>

Signed-off-by: Dmitry Safonov <dima@arista.com>

Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

---

 criu/aio.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/criu/aio.c b/criu/aio.c

index 27c251df5..45651f2d3 100644

--- a/criu/aio.c

+++ b/criu/aio.c

@@ -13,7 +13,7 @@

 #include "images/mm.pb-c.h"

 #include <compel/compel.h>

-#define NR_IOEVENTS_IN_NPAGES(npages) ((PAGE_SIZE * npages - sizeof(struct aio_ring)) / sizeof(struct io_event))

+#define NR_IOEVENTS_IN_NPAGES(npages) ((PAGE_SIZE * (npages) - sizeof(struct aio_ring)) / sizeof(struct io_event))

 int dump_aio_ring(MmEntry *mme, struct vma_area *vma)

 {

-- 

2.17.0