From c20ecf7bb6153149b81a9277eda23398957656f2 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 6 Apr 2023 11:55:31 +0300 Subject: [PATCH] iommu/sva: Fix signedness bug in iommu_sva_alloc_pasid() The ida_alloc_range() function returns negative error codes on error. On success it returns values in the min to max range (inclusive). It never returns more then INT_MAX even if "max" is higher. It never returns values in the 0 to (min - 1) range. The bug is that "min" is an unsigned int so negative error codes will be promoted to high positive values errors treated as success. Fixes: 1a14bf0fc7ed ("iommu/sva: Use GFP_KERNEL for pasid allocation") Signed-off-by: Dan Carpenter Reviewed-by: Lu Baolu Link: https://lore.kernel.org/r/6b32095d-7491-4ebb-a850-12e96209eaaf@kili.mountain Signed-off-by: Joerg Roedel --- drivers/iommu/iommu-sva.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index 3ebd4b6586b3..05c0fb2acbc4 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -34,8 +34,9 @@ static int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t ma } ret = ida_alloc_range(&iommu_global_pasid_ida, min, max, GFP_KERNEL); - if (ret < min) + if (ret < 0) goto out; + mm->pasid = ret; ret = 0; out: