From 1a2742552372585e3c865ce6837624f320985ef6 Mon Sep 17 00:00:00 2001 From: Chao Gao Date: Fri, 19 Aug 2022 16:45:37 +0800 Subject: [PATCH] swiotlb: avoid potential left shift overflow [ Upstream commit 3f0461613ebcdc8c4073e235053d06d5aa58750f ] The second operand passed to slot_addr() is declared as int or unsigned int in all call sites. The left-shift to get the offset of a slot can overflow if swiotlb size is larger than 4G. Convert the macro to an inline function and declare the second argument as phys_addr_t to avoid the potential overflow. Fixes: 26a7e094783d ("swiotlb: refactor swiotlb_tbl_map_single") Signed-off-by: Chao Gao Reviewed-by: Dongli Zhang Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- kernel/dma/swiotlb.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 274587a57717..4a9831d01f0e 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -452,7 +452,10 @@ static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, } } -#define slot_addr(start, idx) ((start) + ((idx) << IO_TLB_SHIFT)) +static inline phys_addr_t slot_addr(phys_addr_t start, phys_addr_t idx) +{ + return start + (idx << IO_TLB_SHIFT); +} /* * Return the offset into a iotlb slot required to keep the device happy.