linux_dsm_epyc7002/tools
Yauheni Kaliuta 4d2cdb2ded selftests/bpf: Mask bpf_csum_diff() return value to 16 bits in test_verifier
commit 6185266c5a853bb0f2a459e3ff594546f277609b upstream.

The verifier test labelled "valid read map access into a read-only array
2" calls the bpf_csum_diff() helper and checks its return value. However,
architecture implementations of csum_partial() (which is what the helper
uses) differ in whether they fold the return value to 16 bit or not. For
example, x86 version has ...

	if (unlikely(odd)) {
		result = from32to16(result);
		result = ((result >> 8) & 0xff) | ((result & 0xff) << 8);
	}

... while generic lib/checksum.c does:

	result = from32to16(result);
	if (odd)
		result = ((result >> 8) & 0xff) | ((result & 0xff) << 8);

This makes the helper return different values on different architectures,
breaking the test on non-x86. To fix this, add an additional instruction
to always mask the return value to 16 bits, and update the expected return
value accordingly.

Fixes: fb2abb73e5 ("bpf, selftest: test {rd, wr}only flags and direct value access")
Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210228103017.320240-1-yauheni.kaliuta@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17 17:06:12 +01:00
..
accounting
arch x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytes 2020-12-06 09:58:13 +01:00
bootconfig tools/bootconfig: Add tracing_on support to helper scripts 2021-01-19 18:27:19 +01:00
bpf tools: Factor HOSTCC, HOSTLD, HOSTAR definitions 2021-01-30 13:55:19 +01:00
build tools: Factor HOSTCC, HOSTLD, HOSTAR definitions 2021-01-30 13:55:19 +01:00
cgroup
debugging
edid
firewire
firmware
gpio tools: gpio: fix %llu warning in gpio-watch.c 2021-01-27 11:55:20 +01:00
hv
iio
include tools headers UAPI: Sync linux/fscrypt.h with the kernel sources 2021-01-17 14:17:06 +01:00
io_uring
kvm/kvm_stat tools/kvm_stat: Exempt time-based counters 2020-12-11 19:18:51 -05:00
laptop
leds
lib libbpf: Ignore non function pointer member in struct_ops 2021-03-04 11:37:33 +01:00
memory-model
objtool objtool: Fix ".cold" section suffix check for newer versions of GCC 2021-03-04 11:38:00 +01:00
pci
pcmcia
perf perf test: Fix unaligned access in sample parsing test 2021-03-04 11:38:10 +01:00
power tools/power/x86/intel-speed-select: Set higher of cpuinfo_max_freq or base_frequency 2021-02-07 15:37:13 +01:00
scripts tools: Factor HOSTCC, HOSTLD, HOSTAR definitions 2021-01-30 13:55:19 +01:00
spi
testing selftests/bpf: Mask bpf_csum_diff() return value to 16 bits in test_verifier 2021-03-17 17:06:12 +01:00
thermal/tmon
time
usb
virtio
vm
wmi
Makefile