From eb0ef4118693caa7ac11c68aeb78d7a4570100bb Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Tue, 19 Mar 2024 11:15:08 -0700 Subject: [PATCH] cxl/core/regs: Fix usage of map->reg_type in cxl_decode_regblock() before assigned [ Upstream commit 5c88a9ccd4c431d58b532e4158b6999a8350062c ] In the error path, map->reg_type is being used for kernel warning before its value is setup. Found by code inspection. Exposure to user is wrong reg_type being emitted via kernel log. Use a local var for reg_type and retrieve value for usage. Fixes: 6c7f4f1e51c2 ("cxl/core/regs: Make cxl_map_{component, device}_regs() device generic") Reviewed-by: Dan Williams Reviewed-by: Davidlohr Bueso Signed-off-by: Dave Jiang Signed-off-by: Sasha Levin --- drivers/cxl/core/regs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c index e0fbe964f6f0a..bab4592db647f 100644 --- a/drivers/cxl/core/regs.c +++ b/drivers/cxl/core/regs.c @@ -271,6 +271,7 @@ EXPORT_SYMBOL_NS_GPL(cxl_map_device_regs, CXL); static bool cxl_decode_regblock(struct pci_dev *pdev, u32 reg_lo, u32 reg_hi, struct cxl_register_map *map) { + u8 reg_type = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BLOCK_ID_MASK, reg_lo); int bar = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BIR_MASK, reg_lo); u64 offset = ((u64)reg_hi << 32) | (reg_lo & CXL_DVSEC_REG_LOCATOR_BLOCK_OFF_LOW_MASK); @@ -278,11 +279,11 @@ static bool cxl_decode_regblock(struct pci_dev *pdev, u32 reg_lo, u32 reg_hi, if (offset > pci_resource_len(pdev, bar)) { dev_warn(&pdev->dev, "BAR%d: %pr: too small (offset: %pa, type: %d)\n", bar, - &pdev->resource[bar], &offset, map->reg_type); + &pdev->resource[bar], &offset, reg_type); return false; } - map->reg_type = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BLOCK_ID_MASK, reg_lo); + map->reg_type = reg_type; map->resource = pci_resource_start(pdev, bar) + offset; map->max_size = pci_resource_len(pdev, bar) - offset; return true;