On little endian platforms, csum_ipv6_magic() keeps len and proto in
CPU byte order. This generates a bad results leading to ICMPv6 packets
from other hosts being dropped by powerpc64le platforms.
In order to fix this, len and proto should be converted to network
byte order ie bigendian byte order. However checksumming 0x12345678
and 0x56341278 provide the exact same result so it is enough to
rotate the sum of len and proto by 1 byte.
PPC32 only support bigendian so the fix is needed for PPC64 only
Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly")
Reported-by: Jianlin Shi <[email protected]>
Reported-by: Xin Long <[email protected]>
Cc: <[email protected]> # 4.18+
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/lib/checksum_64.S | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S
index 886ed94b9c13..2a68c43e13f5 100644
--- a/arch/powerpc/lib/checksum_64.S
+++ b/arch/powerpc/lib/checksum_64.S
@@ -443,6 +443,9 @@ _GLOBAL(csum_ipv6_magic)
addc r0, r8, r9
ld r10, 0(r4)
ld r11, 8(r4)
+#ifndef CONFIG_CPU_BIG_ENDIAN
+ rotldi r5, r5, 8
+#endif
adde r0, r0, r10
add r5, r5, r7
adde r0, r0, r11
--
2.13.3
On Mon, Sep 10, 2018 at 2:09 PM Christophe Leroy
<[email protected]> wrote:
>
> On little endian platforms, csum_ipv6_magic() keeps len and proto in
> CPU byte order. This generates a bad results leading to ICMPv6 packets
> from other hosts being dropped by powerpc64le platforms.
>
> In order to fix this, len and proto should be converted to network
> byte order ie bigendian byte order. However checksumming 0x12345678
> and 0x56341278 provide the exact same result so it is enough to
> rotate the sum of len and proto by 1 byte.
>
> PPC32 only support bigendian so the fix is needed for PPC64 only
>
> Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly")
> Reported-by: Jianlin Shi <[email protected]>
> Reported-by: Xin Long <[email protected]>
> Cc: <[email protected]> # 4.18+
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> arch/powerpc/lib/checksum_64.S | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S
> index 886ed94b9c13..2a68c43e13f5 100644
> --- a/arch/powerpc/lib/checksum_64.S
> +++ b/arch/powerpc/lib/checksum_64.S
> @@ -443,6 +443,9 @@ _GLOBAL(csum_ipv6_magic)
> addc r0, r8, r9
> ld r10, 0(r4)
> ld r11, 8(r4)
> +#ifndef CONFIG_CPU_BIG_ENDIAN
> + rotldi r5, r5, 8
> +#endif
> adde r0, r0, r10
> add r5, r5, r7
> adde r0, r0, r11
> --
> 2.13.3
>
Tested-by: Xin Long <[email protected]>
Hi Michael,
Le 10/09/2018 à 16:28, Xin Long a écrit :
> On Mon, Sep 10, 2018 at 2:09 PM Christophe Leroy
> <[email protected]> wrote:
>>
>> On little endian platforms, csum_ipv6_magic() keeps len and proto in
>> CPU byte order. This generates a bad results leading to ICMPv6 packets
>> from other hosts being dropped by powerpc64le platforms.
>>
>> In order to fix this, len and proto should be converted to network
>> byte order ie bigendian byte order. However checksumming 0x12345678
>> and 0x56341278 provide the exact same result so it is enough to
>> rotate the sum of len and proto by 1 byte.
>>
>> PPC32 only support bigendian so the fix is needed for PPC64 only
>>
>> Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly")
>> Reported-by: Jianlin Shi <[email protected]>
>> Reported-by: Xin Long <[email protected]>
>> Cc: <[email protected]> # 4.18+
>> Signed-off-by: Christophe Leroy <[email protected]>
>> ---
>> arch/powerpc/lib/checksum_64.S | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S
>> index 886ed94b9c13..2a68c43e13f5 100644
>> --- a/arch/powerpc/lib/checksum_64.S
>> +++ b/arch/powerpc/lib/checksum_64.S
>> @@ -443,6 +443,9 @@ _GLOBAL(csum_ipv6_magic)
>> addc r0, r8, r9
>> ld r10, 0(r4)
>> ld r11, 8(r4)
>> +#ifndef CONFIG_CPU_BIG_ENDIAN
>> + rotldi r5, r5, 8
>> +#endif
>> adde r0, r0, r10
>> add r5, r5, r7
>> adde r0, r0, r11
>> --
>> 2.13.3
>>
> Tested-by: Xin Long <[email protected]>
>
Could you take this fix for 4.19 ?
Unless someone takes it through the netdev tree ?
Thanks
Christophe
On Mon, 2018-09-10 at 06:09:04 UTC, Christophe Leroy wrote:
> On little endian platforms, csum_ipv6_magic() keeps len and proto in
> CPU byte order. This generates a bad results leading to ICMPv6 packets
> from other hosts being dropped by powerpc64le platforms.
>
> In order to fix this, len and proto should be converted to network
> byte order ie bigendian byte order. However checksumming 0x12345678
> and 0x56341278 provide the exact same result so it is enough to
> rotate the sum of len and proto by 1 byte.
>
> PPC32 only support bigendian so the fix is needed for PPC64 only
>
> Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly")
> Reported-by: Jianlin Shi <[email protected]>
> Reported-by: Xin Long <[email protected]>
> Cc: <[email protected]> # 4.18+
> Signed-off-by: Christophe Leroy <[email protected]>
> Tested-by: Xin Long <[email protected]>
Applied to powerpc fixes, thanks.
https://git.kernel.org/powerpc/c/85682a7e3b9c664995ad477520f917
cheers