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| author | karl beldan <karl.beldan@gmail.com> | 2015-01-28 10:58:11 +0100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2015-03-06 00:39:18 +0000 |
| commit | c544b4bf9ad9f10d48ac0bd720a4c0124a9c6d41 (patch) | |
| tree | 496a36b9210786d8e4790ce1a106d5a22cb0ca9d /lib | |
| parent | 5c8edb8faee3068348fa040c22568f132e3643fa (diff) | |
| download | kernel_samsung_smdk4412-c544b4bf9ad9f10d48ac0bd720a4c0124a9c6d41.zip kernel_samsung_smdk4412-c544b4bf9ad9f10d48ac0bd720a4c0124a9c6d41.tar.gz kernel_samsung_smdk4412-c544b4bf9ad9f10d48ac0bd720a4c0124a9c6d41.tar.bz2 | |
lib/checksum.c: fix carry in csum_tcpudp_nofold
commit 150ae0e94634714b23919f0c333fee28a5b199d5 upstream.
The carry from the 64->32bits folding was dropped, e.g with:
saddr=0xFFFFFFFF daddr=0xFF0000FF len=0xFFFF proto=0 sum=1,
csum_tcpudp_nofold returned 0 instead of 1.
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/checksum.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/lib/checksum.c b/lib/checksum.c index 8df2f91..50f9abd 100644 --- a/lib/checksum.c +++ b/lib/checksum.c @@ -47,6 +47,15 @@ static inline unsigned short from32to16(unsigned int x) return x; } +static inline u32 from64to32(u64 x) +{ + /* add up 32-bit and 32-bit for 32+c bit */ + x = (x & 0xffffffff) + (x >> 32); + /* add up carry.. */ + x = (x & 0xffffffff) + (x >> 32); + return (u32)x; +} + static unsigned int do_csum(const unsigned char *buff, int len) { int odd; @@ -193,8 +202,7 @@ __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, #else s += (proto + len) << 8; #endif - s += (s >> 32); - return (__force __wsum)s; + return (__force __wsum)from64to32(s); } EXPORT_SYMBOL(csum_tcpudp_nofold); #endif |