From: Evgeny Novikov novikov@ispras.ru
[ 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 novikov@ispras.ru Co-developed-by: Kirill Shilimanov kirill.shilimanov@huawei.com Signed-off-by: Kirill Shilimanov kirill.shilimanov@huawei.com Co-developed-by: Anton Vasilyev vasilyev@ispras.ru Signed-off-by: Anton Vasilyev vasilyev@ispras.ru Signed-off-by: Miquel Raynal miquel.raynal@bootlin.com Link: https://lore.kernel.org/linux-mtd/20210903082653.16441-1-novikov@ispras.ru Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mtd/nand/raw/intel-nand-controller.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/mtd/nand/raw/intel-nand-controller.c b/drivers/mtd/nand/raw/intel-nand-controller.c index b9784f3da7a11..7c1c80dae826a 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);