Willy Tarreau 4acb99f867 BUG/MINOR: xxhash: make sure armv6 uses memcpy() ... There was a special case made to allow ARMv6 to use unaligned accesses via a cast in xxHash when __ARM_FEATURE_UNALIGNED is defined. But while ARMv6 (and v7) does support unaligned accesses, it's only for 32-bit pointers, not 64-bit ones, leading to bus errors when the compiler emits an ldrd instruction and the input (e.g. a pattern) is not aligned, as in issue #1035. Note that v7 was properly using the packed approach here and was safe, however haproxy versions 2.3 and older use the old r39 xxhash code which has the same issue for armv7. A slightly different fix is required there, by using a different definition of packed for 32 and 64 bits. The problem is really visible when running v7 code on a v8 kernel because such kernels do not implement alignment trap emulation, and the process dies when this happens. This is why in the issue above it was only detected under lxc. The emulation could have been disabled on v7 as well by writing zero to /proc/cpu/alignment though. This commit is a backport of xxhash commit a470f2ef ("update default memory access for armv6"). Thanks to @srkunze for the report and tests, @stgraber for his help on setting up an easy reproducer outside of lxc, and @Cyan4973 for the discussion around the best way to fix this. Details and alternate patches available on https://github.com/Cyan4973/xxHash/issues/490.		2021-02-04 17:14:58 +01:00
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haproxy	MEDIUM: check: align agentaddr and agentport behaviour	2021-02-04 14:00:38 +01:00
import	BUG/MINOR: xxhash: make sure armv6 uses memcpy()	2021-02-04 17:14:58 +01:00