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

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>
Acked-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Fixes: 358bdf892f ("clk: stm32: Add clock driver for STM32F4[23]xxx devices")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This commit is contained in:
Daniel Thompson 2015-06-28 10:55:32 +01:00 committed by Stephen Boyd
parent 69916d9609
commit 15ab38273d

View File

@ -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;