Re: [PATCH] powerpc/nvram: use memdup_user
From: Kees Cook <hidden>
Date: 2017-06-28 00:08:07
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On Fri, Apr 28, 2017 at 6:45 PM, Geliang Tang [off-list ref] wrote:
Use memdup_user() helper instead of open-coding to simplify the code. Signed-off-by: Geliang Tang <redacted>
Thanks! Applied for -next. -Kees
quoted hunk ↗ jump to hunk
--- arch/powerpc/kernel/nvram_64.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-)diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c index eae61b0..496d639 100644 --- a/arch/powerpc/kernel/nvram_64.c +++ b/arch/powerpc/kernel/nvram_64.c@@ -792,21 +792,17 @@ static ssize_t dev_nvram_write(struct file *file, const char __user *buf, count = min_t(size_t, count, size - *ppos); count = min(count, PAGE_SIZE); - ret = -ENOMEM; - tmp = kmalloc(count, GFP_KERNEL); - if (!tmp) - goto out; - - ret = -EFAULT; - if (copy_from_user(tmp, buf, count)) + tmp = memdup_user(buf, count); + if (IS_ERR(tmp)) { + ret = PTR_ERR(tmp); goto out; + } ret = ppc_md.nvram_write(tmp, count, ppos); -out: kfree(tmp); +out: return ret; - } static long dev_nvram_ioctl(struct file *file, unsigned int cmd, --2.9.3
-- Kees Cook Pixel Security