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    SubjectRe: [PATCH 5.10 424/530] cxgb4: Fix unintentional sign extension issues
    Hi!

    > From: Colin Ian King <colin.king@canonical.com>

    > 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.

    Should we really use -stable series for beta-testing patches going to
    -rc1? Because that's what Sasha is effectively doing.

    > Addresses-Coverity: ("Unintended sign extension")
    > Fixes: 12b276fbf6e0 ("cxgb4: add support to create hash filters")
    > Signed-off-by: Colin Ian King <colin.king@canonical.com>
    > Signed-off-by: David S. Miller <davem@davemloft.net>
    > Signed-off-by: Sasha Levin <sashal@kernel.org>

    > 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);
    > }
    > }


    This one is wrong.

    Best regards,
    Pavel
    --
    http://www.livejournal.com/~pavelmachek
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