From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kefeng Wang Subject: [PATCH 3/3] i2c: i801: avoid panic if ioreamp fails Date: Fri, 10 May 2019 11:03:20 +0800 Message-ID: <20190510030320.109154-3-wangkefeng.wang@huawei.com> References: <20190510030320.109154-1-wangkefeng.wang@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <20190510030320.109154-1-wangkefeng.wang@huawei.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org Cc: Kefeng Wang , Jean Delvare , Wolfram Sang , linux-i2c@vger.kernel.org, Hulk Robot List-Id: linux-i2c@vger.kernel.org If ioremap fails, NULL pointer dereference will happen and leading to a kernel panic when access the virtual address in check_signature(). Fix it by check the return value of ioremap. Cc: Jean Delvare Cc: Wolfram Sang Cc: linux-i2c@vger.kernel.org Reported-by: Hulk Robot Signed-off-by: Kefeng Wang --- drivers/i2c/busses/i2c-i801.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 679c6c41f64b..fc6ccb8aba17 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -1068,7 +1068,10 @@ static void __init input_apanel_init(void) void __iomem *bios; const void __iomem *p; - bios = ioremap(0xF0000, 0x10000); /* Can't fail */ + bios = ioremap(0xF0000, 0x10000); + if (!base) + return -ENOMEM; + p = bios_signature(bios); if (p) { /* just use the first address */ -- 2.20.1