From 5788929e05e18ed5f76dc8ade4210f022c9ba5a1 Mon Sep 17 00:00:00 2001 From: Ethan Milon Date: Tue, 17 Jun 2025 15:04:27 +0000 Subject: [PATCH] amd_iommu: Fix truncation of oldval in amdvi_writeq The variable `oldval` was incorrectly declared as a 32-bit `uint32_t`. This could lead to truncation and incorrect behavior where the upper read-only 32 bits are significant. Fix the type of `oldval` to match the return type of `ldq_le_p()`. Cc: qemu-stable@nongnu.org Fixes: d29a09ca6842 ("hw/i386: Introduce AMD IOMMU") Signed-off-by: Ethan Milon Message-Id: <20250617150427.20585-9-alejandro.j.jimenez@oracle.com> Reviewed-by: Vasant Hegde Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/amd_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c index 92f94dc788..5a24c17548 100644 --- a/hw/i386/amd_iommu.c +++ b/hw/i386/amd_iommu.c @@ -140,7 +140,7 @@ static void amdvi_writeq(AMDVIState *s, hwaddr addr, uint64_t val) { uint64_t romask = ldq_le_p(&s->romask[addr]); uint64_t w1cmask = ldq_le_p(&s->w1cmask[addr]); - uint32_t oldval = ldq_le_p(&s->mmior[addr]); + uint64_t oldval = ldq_le_p(&s->mmior[addr]); stq_le_p(&s->mmior[addr], ((oldval & romask) | (val & ~romask)) & ~(val & w1cmask)); } -- 2.47.2