[PATCH v2] i2c: cpm: Fix i2c_ram structure

nico.vince at gmail.com nico.vince at gmail.com
Thu Sep 24 00:08:40 AEST 2020


From: Nicolas VINCENT <nicolas.vincent at vossloh.com>

the i2c_ram structure is missing the sdmatmp field mentionned in
datasheet for MPC8272 at paragraph 36.5. With this field missing, the
hardware would write past the allocated memory done through
cpm_muram_alloc for the i2c_ram structure and land in memory allocated
for the buffers descriptors corrupting the cbd_bufaddr field. Since this
field is only set during setup(), the first i2c transaction would work
and the following would send data read from an arbitrary memory
location.

Signed-off-by: Nicolas VINCENT <nicolas.vincent at vossloh.com>
---
 drivers/i2c/busses/i2c-cpm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c
index 1213e1932ccb..24d584a1c9a7 100644
--- a/drivers/i2c/busses/i2c-cpm.c
+++ b/drivers/i2c/busses/i2c-cpm.c
@@ -65,6 +65,9 @@ struct i2c_ram {
 	char    res1[4];	/* Reserved */
 	ushort  rpbase;		/* Relocation pointer */
 	char    res2[2];	/* Reserved */
+	/* The following elements are only for CPM2 */
+	char    res3[4];	/* Reserved */
+	uint    sdmatmp;	/* Internal */
 };
 
 #define I2COM_START	0x80
-- 
2.17.1



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