diff mbox

clk: stm32: Fix out-by-one error path in the index lookup

Message ID 1435485332-14951-1-git-send-email-daniel.thompson@linaro.org
State Accepted
Commit 15ab38273d21a45487116ad4c428593427954848
Headers show

Commit Message

Daniel Thompson June 28, 2015, 9:55 a.m. UTC
If stm32f4_rcc_lookup() is called with primary == 0 and secondary == 192
then it will read beyond the end of the table array due to an out-by-one
error in the range check.

In addition to the fixing the inequality we also modify the r.h.s. to
make it even more explicit that we are comparing against the size of
table in bits.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 drivers/clk/clk-stm32f4.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--
2.4.3
diff mbox

Patch

diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c
index c825bbd..148c151 100644
--- a/drivers/clk/clk-stm32f4.c
+++ b/drivers/clk/clk-stm32f4.c
@@ -268,7 +268,7 @@  static int stm32f4_rcc_lookup_clk_idx(u8 primary, u8 secondary)
 	memcpy(table, stm32f42xx_gate_map, sizeof(table));

 	/* only bits set in table can be used as indices */
-	if (WARN_ON(secondary > 8 * sizeof(table) ||
+	if (WARN_ON(secondary >= BITS_PER_BYTE * sizeof(table) ||
 		    0 == (table[BIT_ULL_WORD(secondary)] &
 			  BIT_ULL_MASK(secondary))))
 		return -EINVAL;