From: Evgeny Novikov Date: Fri, 3 Sep 2021 08:26:53 +0000 (+0300) Subject: mtd: rawnand: intel: Fix potential buffer overflow in probe X-Git-Tag: v5.14.19~196 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b33831877a0e8520968dba8dfbb399e0890f3d51;p=thirdparty%2Fkernel%2Fstable.git mtd: rawnand: intel: Fix potential buffer overflow in probe [ Upstream commit 46a0dc10fb32bec3e765e51bf71fbc070dc77ca3 ] ebu_nand_probe() read the value of u32 variable "cs" from the device firmware description and used it as the index for array ebu_host->cs that can contain MAX_CS (2) elements at most. That could result in a buffer overflow and various bad consequences later. Fix the potential buffer overflow by restricting values of "cs" with MAX_CS in probe. Found by Linux Driver Verification project (linuxtesting.org). Fixes: 0b1039f016e8 ("mtd: rawnand: Add NAND controller support on Intel LGM SoC") Signed-off-by: Evgeny Novikov Co-developed-by: Kirill Shilimanov Signed-off-by: Kirill Shilimanov Co-developed-by: Anton Vasilyev Signed-off-by: Anton Vasilyev Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/20210903082653.16441-1-novikov@ispras.ru Signed-off-by: Sasha Levin --- diff --git a/drivers/mtd/nand/raw/intel-nand-controller.c b/drivers/mtd/nand/raw/intel-nand-controller.c index 29e8a546dcd60..e8476cd5147fe 100644 --- a/drivers/mtd/nand/raw/intel-nand-controller.c +++ b/drivers/mtd/nand/raw/intel-nand-controller.c @@ -609,6 +609,11 @@ static int ebu_nand_probe(struct platform_device *pdev) dev_err(dev, "failed to get chip select: %d\n", ret); return ret; } + if (cs >= MAX_CS) { + dev_err(dev, "got invalid chip select: %d\n", cs); + return -EINVAL; + } + ebu_host->cs_num = cs; resname = devm_kasprintf(dev, GFP_KERNEL, "nand_cs%d", cs);