diff mbox series

nvmem: meson-mx-efuse: allow reading data smaller than word_size

Message ID 20190727191958.27240-1-martin.blumenstingl@googlemail.com (mailing list archive)
State New, archived
Headers show
Series nvmem: meson-mx-efuse: allow reading data smaller than word_size | expand

Commit Message

Martin Blumenstingl July 27, 2019, 7:19 p.m. UTC 
Some Amlogic boards store the Ethernet MAC address inside the eFuse. The
Ethernet MAC address uses 6 bytes. The existing logic in
meson_mx_efuse_read() would write beyond the end of the data buffer when
trying to read data with a size that is not aligned to word_size (4
bytes on Meson8, Meson8b and Meson8m2).

Calculate the remaining data to copy inside meson_mx_efuse_read() so
reading 6 bytes doesn't write beyond the end of the data buffer.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
 drivers/nvmem/meson-mx-efuse.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/nvmem/meson-mx-efuse.c b/drivers/nvmem/meson-mx-efuse.c
index 2976aef87c82..d5ccde1abd8e 100644
--- a/drivers/nvmem/meson-mx-efuse.c
+++ b/drivers/nvmem/meson-mx-efuse.c
@@ -155,7 +155,7 @@  static int meson_mx_efuse_read(void *context, unsigned int offset,
 		if (err)
 			break;
 
-		memcpy(buf + i, &tmp, efuse->config.word_size);
+		memcpy(buf + i, &tmp, min(bytes - i, efuse->config.word_size));
 	}
 
 	meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1,