From: Bhupinder Thakur Date: Fri, 29 Sep 2017 05:59:46 +0000 (+0530) Subject: xen/arm: Fix the issue in cmp_mmio_handler used in find_mmio_handler X-Git-Tag: 4.10.0-rc1~201 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=b7ed331353a14f43f53eaf6a3a543ec8385193a3;p=people%2Fdariof%2Fxen.git xen/arm: Fix the issue in cmp_mmio_handler used in find_mmio_handler This patch fixes the wrong range check done in cmp_mmio_handler(). This function returns -1 , 0 or 1 based on whether the key value is below the range, in the range or above the range where the range is (start, start+size). However, it should check against (start, start+size-1) because start+size falls outside the range. This resulted in returning a wrong mmio_handler for a given mmio address which happened to be start+size. This bug was introduced when the mmio region search switched from linear search to binary search in the following commit: 8047e09 "xen/arm: io: Use binary search for mmio handler lookup". Signed-off-by: Bhupinder Thakur Signed-off-by: Stefano Stabellini Reviewed-by: Stefano Stabellini --- diff --git a/xen/arch/arm/io.c b/xen/arch/arm/io.c index e2161289a3..c748d8f5bf 100644 --- a/xen/arch/arm/io.c +++ b/xen/arch/arm/io.c @@ -79,7 +79,7 @@ static int cmp_mmio_handler(const void *key, const void *elem) if ( handler0->addr < handler1->addr ) return -1; - if ( handler0->addr > (handler1->addr + handler1->size) ) + if ( handler0->addr >= (handler1->addr + handler1->size) ) return 1; return 0;