From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Mon, 19 Oct 2015 11:19:01 +0000 Subject: [patch 2/2 v2] misc: mic/scif: fix wrap around tests Message-Id: <20151019111901.GA29692@mwanda> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Ashutosh Dixit , Sudeep Dutt Cc: Nikhil Rao , linux-kernel@vger.kernel.org, Greg Kroah-Hartman , kernel-janitors@vger.kernel.org Signed integer overflow is undefined. Also I added a check for "(offset < 0)" in scif_unregister() because that makes it match the other conditions and because I didn't want to subtract a negative. Fixes: ba612aa8b487 ('misc: mic: SCIF memory registration and unregistration') Signed-off-by: Dan Carpenter --- I reversed a condition in the first version of this patch. diff --git a/drivers/misc/mic/scif/scif_rma.c b/drivers/misc/mic/scif/scif_rma.c index bc2dccb..245ea9b 100644 --- a/drivers/misc/mic/scif/scif_rma.c +++ b/drivers/misc/mic/scif/scif_rma.c @@ -1510,7 +1510,7 @@ off_t scif_register_pinned_pages(scif_epd_t epd, if ((map_flags & SCIF_MAP_FIXED) && ((ALIGN(offset, PAGE_SIZE) != offset) || (offset < 0) || - (offset + (off_t)len < offset))) + (len > LONG_MAX - offset))) return -EINVAL; might_sleep(); @@ -1613,7 +1613,7 @@ off_t scif_register(scif_epd_t epd, void *addr, size_t len, off_t offset, if ((map_flags & SCIF_MAP_FIXED) && ((ALIGN(offset, PAGE_SIZE) != offset) || (offset < 0) || - (offset + (off_t)len < offset))) + (len > LONG_MAX - offset))) return -EINVAL; /* Unsupported protection requested */ @@ -1731,7 +1731,8 @@ scif_unregister(scif_epd_t epd, off_t offset, size_t len) /* Offset is not page aligned or offset+len wraps around */ if ((ALIGN(offset, PAGE_SIZE) != offset) || - (offset + (off_t)len < offset)) + (offset < 0) || + (len > LONG_MAX - offset)) return -EINVAL; err = scif_verify_epd(ep);