of: fix of_device_get_modalias returned length when truncating buffers

[ Upstream commit bcf54d5385abaea9c8026aae6f4eeb348671a52d ]

If the length of the modalias is greater than the buffer size, then the
modalias is truncated. However the untruncated length is returned which
will cause an error. Fix this to return the truncated length. If an error
in the case was desired, then then we should just return -ENOMEM.

The reality is no device will ever have 4KB of compatible strings to hit
this case.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/of/device.c b/drivers/of/device.c
index 97a280d50d6d8d1a56135a3481c98220e8ecbd0e..7c509bff92959b6803d5f110166f90d92c8d011d 100644 (file)
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -223,7 +223,7 @@ ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
                        str[i] = '_';
        }
 
-       return tsize;
+       return repend;
 }
 EXPORT_SYMBOL_GPL(of_device_get_modalias);