EDAC, amd64_edac: Shift wrapping issue in f1x_get_norm_dct_addr()

dct_sel_base_off is declared as a u64 but we're only using the lower 32
bits because of a shift wrapping bug. This can possibly truncate the
upper 16 bits of DctSelBaseOffset[47:26], causing us to misdecode the CS
row.

Fixes: c8e518d5673d ('amd64_edac: Sanitize f10_get_base_addr_offset')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20160120095451.GB19898@mwanda
Signed-off-by: Borislav Petkov <bp@suse.de>

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 9eee13ef83a560fd0c54153c61bc01a77cd3eb7f..d87a47547ba59933d719d39cf1fe1460df2eeb55 100644 (file)
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -1452,7 +1452,7 @@ static u64 f1x_get_norm_dct_addr(struct amd64_pvt *pvt, u8 range,
        u64 chan_off;
        u64 dram_base           = get_dram_base(pvt, range);
        u64 hole_off            = f10_dhar_offset(pvt);
-       u64 dct_sel_base_off    = (pvt->dct_sel_hi & 0xFFFFFC00) << 16;
+       u64 dct_sel_base_off    = (u64)(pvt->dct_sel_hi & 0xFFFFFC00) << 16;
 
        if (hi_rng) {
                /*