This is a note to let you know that I've just added the patch titled PCI: rcar-ep: Fix incorrect variable used when calling devm_request_mem_region() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pci-rcar-ep-fix-incorrect-variable-used-when-calling.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit cd5d7716e645bc9b38c201508f78187f288a0083 Author: King Dix <kingdix10@xxxxxx> Date: Thu Jan 9 08:50:18 2025 +0800 PCI: rcar-ep: Fix incorrect variable used when calling devm_request_mem_region() [ Upstream commit 2d2da5a4c1b4509f6f7e5a8db015cd420144beb4 ] The rcar_pcie_parse_outbound_ranges() uses the devm_request_mem_region() macro to request a needed resource. A string variable that lives on the stack is then used to store a dynamically computed resource name, which is then passed on as one of the macro arguments. This can lead to undefined behavior. Depending on the current contents of the memory, the manifestations of errors may vary. One possible output may be as follows: $ cat /proc/iomem 30000000-37ffffff : 38000000-3fffffff : Sometimes, garbage may appear after the colon. In very rare cases, if no NULL-terminator is found in memory, the system might crash because the string iterator will overrun which can lead to access of unmapped memory above the stack. Thus, fix this by replacing outbound_name with the name of the previously requested resource. With the changes applied, the output will be as follows: $ cat /proc/iomem 30000000-37ffffff : memory2 38000000-3fffffff : memory3 Fixes: 2a6d0d63d999 ("PCI: rcar: Add endpoint mode support") Link: https://lore.kernel.org/r/tencent_DBDCC19D60F361119E76919ADAB25EC13C06@xxxxxx Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> Signed-off-by: King Dix <kingdix10@xxxxxx> [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński <kwilczynski@xxxxxxxxxx> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/pci/controller/pcie-rcar-ep.c b/drivers/pci/controller/pcie-rcar-ep.c index c91d85b151290..fc85263797e91 100644 --- a/drivers/pci/controller/pcie-rcar-ep.c +++ b/drivers/pci/controller/pcie-rcar-ep.c @@ -110,7 +110,7 @@ static int rcar_pcie_parse_outbound_ranges(struct rcar_pcie_endpoint *ep, } if (!devm_request_mem_region(&pdev->dev, res->start, resource_size(res), - outbound_name)) { + res->name)) { dev_err(pcie->dev, "Cannot request memory region %s.\n", outbound_name); return -EIO;