WSL2-Linux-Kernel/arch/parisc
Guenter Roeck 0552d5727e parisc: Strip upper 32 bit of sum in csum_ipv6_magic for 64-bit builds
[ Upstream commit 0568b6f0d863643db2edcc7be31165740c89fa82 ]

IPv6 checksum tests with unaligned addresses on 64-bit builds result
in unexpected failures.

Expected expected == csum_result, but
    expected == 46591 (0xb5ff)
    csum_result == 46381 (0xb52d)
with alignment offset 1

Oddly enough, the problem disappeared after adding test code into
the beginning of csum_ipv6_magic().

As it turns out, the 'sum' parameter of csum_ipv6_magic() is declared as
__wsum, which is a 32-bit variable. However, it is treated as 64-bit
variable in the 64-bit assembler code. Tests showed that the upper 32 bit
of the register used to pass the variable are _not_ cleared when entering
the function. This can result in checksum calculation errors.

Clearing the upper 32 bit of 'sum' as first operation in the assembler
code fixes the problem.

Acked-by: Helge Deller <deller@gmx.de>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-10 16:18:36 +02:00
..
boot parisc: Add missing FORCE prerequisite in Makefile 2021-09-09 12:44:30 +02:00
configs configs: remove the obsolete CONFIG_INPUT_POLLDEV 2021-09-08 11:50:28 -07:00
include parisc: Strip upper 32 bit of sum in csum_ipv6_magic for 64-bit builds 2024-04-10 16:18:36 +02:00
kernel parisc/ftrace: add missing CONFIG_DYNAMIC_FTRACE check 2024-03-26 18:21:13 -04:00
lib parisc: Add ioread64_lo_hi() and iowrite64_lo_hi() 2022-02-23 12:03:04 +01:00
math-emu parisc: math-emu: Fix fall-through warnings 2021-09-01 22:18:18 +02:00
mm parisc: Fix handling off probe non-access faults 2022-04-08 14:23:56 +02:00
Kbuild parisc: move core-y in arch/parisc/Makefile to arch/parisc/Kbuild 2021-08-30 10:18:25 +02:00
Kconfig parisc: Allow CONFIG_64BIT with ARCH=parisc 2022-09-23 14:15:48 +02:00
Kconfig.debug tracing: Refactor TRACE_IRQFLAGS_SUPPORT in Kconfig 2021-08-16 11:37:21 -04:00
Makefile parisc: Fix KBUILD_IMAGE for self-extracting kernel 2021-12-08 09:04:55 +01:00
defpalo.conf
install.sh parisc: Fix "make install" on newer debian releases 2021-12-08 09:04:55 +01:00
nm