From: Andrew Rybchenko Date: Fri, 26 Aug 2016 10:19:34 +0000 (+0100) Subject: sfc: fix potential stack corruption from running past stat bitmask X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e70c70c38d7a5ced76fc8b1c4a7ccee76e9c2911;p=linux-beck.git sfc: fix potential stack corruption from running past stat bitmask On 32-bit systems, mask is only an array of 3 longs, not 4, so don't try to write to mask[3]. Also include build-time checks in case the size of the bitmask changes. Fixes: 3c36a2aded8c ("sfc: display vadaptor statistics for all interfaces") Signed-off-by: Edward Cree Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c index f658fee74f18..e00a669e9e09 100644 --- a/drivers/net/ethernet/sfc/ef10.c +++ b/drivers/net/ethernet/sfc/ef10.c @@ -1517,13 +1517,14 @@ static void efx_ef10_get_stat_mask(struct efx_nic *efx, unsigned long *mask) } #if BITS_PER_LONG == 64 + BUILD_BUG_ON(BITS_TO_LONGS(EF10_STAT_COUNT) != 2); mask[0] = raw_mask[0]; mask[1] = raw_mask[1]; #else + BUILD_BUG_ON(BITS_TO_LONGS(EF10_STAT_COUNT) != 3); mask[0] = raw_mask[0] & 0xffffffff; mask[1] = raw_mask[0] >> 32; mask[2] = raw_mask[1] & 0xffffffff; - mask[3] = raw_mask[1] >> 32; #endif }