diff mbox

[1/4] nvmem: core: return error for non word aligned access

Message ID 1450086158-18756-1-git-send-email-srinivas.kandagatla@linaro.org
State Accepted
Commit 2f9ba5b2f8420e0e5712080dafc773f7dd47c3df
Headers show

Commit Message

Srinivas Kandagatla Dec. 14, 2015, 9:42 a.m. UTC
nvmem providers have restrictions on register strides, so return error
when users attempt to read/write buffers with sizes which are less
than word size.

Without this patch the userspace would continue to try as it does not
get any error from the nvmem core, resulting in a hang or endless loop
in userspace.

Reported-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

---
 drivers/nvmem/core.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
1.9.1

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diff mbox

Patch

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 6fd4e5a..9d11d98 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -70,6 +70,9 @@  static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj,
 	if (pos >= nvmem->size)
 		return 0;
 
+	if (count < nvmem->word_size)
+		return -EINVAL;
+
 	if (pos + count > nvmem->size)
 		count = nvmem->size - pos;
 
@@ -95,6 +98,9 @@  static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
 	if (pos >= nvmem->size)
 		return 0;
 
+	if (count < nvmem->word_size)
+		return -EINVAL;
+
 	if (pos + count > nvmem->size)
 		count = nvmem->size - pos;