[PATCH] cxgb4: Fix unintentional sign extension issues

From: Colin King
Date: Fri Apr 09 2021 - 07:09:08 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

The shifting of the u8 integers f->fs.nat_lip[] by 24 bits to
the left will be promoted to a 32 bit signed int and then
sign-extended to a u64. In the event that the top bit of the u8
is set then all then all the upper 32 bits of the u64 end up as
also being set because of the sign-extension. Fix this by
casting the u8 values to a u64 before the 24 bit left shift.

Addresses-Coverity: ("Unintended sign extension")
Fixes: 12b276fbf6e0 ("cxgb4: add support to create hash filters")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
.../net/ethernet/chelsio/cxgb4/cxgb4_filter.c | 22 +++++++++----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
index b1cae5a19839..2f70f02207b2 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
@@ -174,31 +174,31 @@ static void set_nat_params(struct adapter *adap, struct filter_entry *f,
WORD_MASK, f->fs.nat_lip[15] |
f->fs.nat_lip[14] << 8 |
f->fs.nat_lip[13] << 16 |
- f->fs.nat_lip[12] << 24, 1);
+ (u64)f->fs.nat_lip[12] << 24, 1);

set_tcb_field(adap, f, tid, TCB_SND_UNA_RAW_W + 1,
WORD_MASK, f->fs.nat_lip[11] |
f->fs.nat_lip[10] << 8 |
f->fs.nat_lip[9] << 16 |
- f->fs.nat_lip[8] << 24, 1);
+ (u64)f->fs.nat_lip[8] << 24, 1);

set_tcb_field(adap, f, tid, TCB_SND_UNA_RAW_W + 2,
WORD_MASK, f->fs.nat_lip[7] |
f->fs.nat_lip[6] << 8 |
f->fs.nat_lip[5] << 16 |
- f->fs.nat_lip[4] << 24, 1);
+ (u64)f->fs.nat_lip[4] << 24, 1);

set_tcb_field(adap, f, tid, TCB_SND_UNA_RAW_W + 3,
WORD_MASK, f->fs.nat_lip[3] |
f->fs.nat_lip[2] << 8 |
f->fs.nat_lip[1] << 16 |
- f->fs.nat_lip[0] << 24, 1);
+ (u64)f->fs.nat_lip[0] << 24, 1);
} else {
set_tcb_field(adap, f, tid, TCB_RX_FRAG3_LEN_RAW_W,
WORD_MASK, f->fs.nat_lip[3] |
f->fs.nat_lip[2] << 8 |
f->fs.nat_lip[1] << 16 |
- f->fs.nat_lip[0] << 24, 1);
+ (u64)f->fs.nat_lip[0] << 25, 1);
}
}

@@ -208,25 +208,25 @@ static void set_nat_params(struct adapter *adap, struct filter_entry *f,
WORD_MASK, f->fs.nat_fip[15] |
f->fs.nat_fip[14] << 8 |
f->fs.nat_fip[13] << 16 |
- f->fs.nat_fip[12] << 24, 1);
+ (u64)f->fs.nat_fip[12] << 24, 1);

set_tcb_field(adap, f, tid, TCB_RX_FRAG2_PTR_RAW_W + 1,
WORD_MASK, f->fs.nat_fip[11] |
f->fs.nat_fip[10] << 8 |
f->fs.nat_fip[9] << 16 |
- f->fs.nat_fip[8] << 24, 1);
+ (u64)f->fs.nat_fip[8] << 24, 1);

set_tcb_field(adap, f, tid, TCB_RX_FRAG2_PTR_RAW_W + 2,
WORD_MASK, f->fs.nat_fip[7] |
f->fs.nat_fip[6] << 8 |
f->fs.nat_fip[5] << 16 |
- f->fs.nat_fip[4] << 24, 1);
+ (u64)f->fs.nat_fip[4] << 24, 1);

set_tcb_field(adap, f, tid, TCB_RX_FRAG2_PTR_RAW_W + 3,
WORD_MASK, f->fs.nat_fip[3] |
f->fs.nat_fip[2] << 8 |
f->fs.nat_fip[1] << 16 |
- f->fs.nat_fip[0] << 24, 1);
+ (u64)f->fs.nat_fip[0] << 24, 1);

} else {
set_tcb_field(adap, f, tid,
@@ -234,13 +234,13 @@ static void set_nat_params(struct adapter *adap, struct filter_entry *f,
WORD_MASK, f->fs.nat_fip[3] |
f->fs.nat_fip[2] << 8 |
f->fs.nat_fip[1] << 16 |
- f->fs.nat_fip[0] << 24, 1);
+ (u64)f->fs.nat_fip[0] << 24, 1);
}
}

set_tcb_field(adap, f, tid, TCB_PDU_HDR_LEN_W, WORD_MASK,
(dp ? (nat_lp[1] | nat_lp[0] << 8) : 0) |
- (sp ? (nat_fp[1] << 16 | nat_fp[0] << 24) : 0),
+ (sp ? (nat_fp[1] << 16 | (u64)nat_fp[0] << 24) : 0),
1);
}

--
2.30.2