diff options
author | Paul Mackerras <paulus@ozlabs.org> | 2016-11-03 16:10:55 +1100 |
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committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-01-25 13:34:18 +1100 |
commit | b492f7e4e07a28e706db26cf4943bb0911435426 (patch) | |
tree | 2e5ce673c7553a9faccc17100785235cc8df9d0d /arch/powerpc/lib | |
parent | 14a41d6b7572026cf8fc88ee72e81b6b40db2ec0 (diff) |
powerpc/64: Fix checksum folding in csum_tcpudp_nofold and ip_fast_csum_nofold
These functions compute an IP checksum by computing a 64-bit sum and
folding it to 32 bits (the "nofold" in their names refers to folding
down to 16 bits). However, doing (u32) (s + (s >> 32)) is not
sufficient to fold a 64-bit sum to 32 bits correctly. The addition
can produce a carry out from bit 31, which needs to be added in to
the sum to produce the correct result.
To fix this, we copy the from64to32() function from lib/checksum.c
and use that.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/lib')
0 files changed, 0 insertions, 0 deletions