asm/current.h is included by some assembly files (either directly, or
indirectly). This works on some architectures (such as x86), as their
implementation of current.h is careful to not include any C, but the
asm-generic version includes linux/thread-info.h unconditionally, which
leads to errors when either C code or non-asm-compatible preprocessor
directives are included.
Just wrap the contents behind an #ifndef __ASSEMBLY__ to avoid any C
code making its way in.
Signed-off-by: David Gow <davidgow(a)google.com>
---
This is requrired for patch #2 here, as UML uses this asm-generic
header, but works with x86 assembly files which are expecting the x86
current.h, which is assembly-friendly.
---
include/asm-generic/current.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/include/asm-generic/current.h b/include/asm-generic/current.h
index 3a2e224b9fa0..9c2aeecbd05a 100644
--- a/include/asm-generic/current.h
+++ b/include/asm-generic/current.h
@@ -2,9 +2,11 @@
#ifndef __ASM_GENERIC_CURRENT_H
#define __ASM_GENERIC_CURRENT_H
+#ifndef __ASSEMBLY__
#include <linux/thread_info.h>
#define get_current() (current_thread_info()->task)
#define current get_current()
+#endif
#endif /* __ASM_GENERIC_CURRENT_H */
--
2.41.0.255.g8b1d071c50-goog
Greetings from Ukraine,
Mr. Razumkov Mykhailo, an entrepreneur businessman from Odessa
Ukraine. Within a year plus some months now, more than 8.2 million
people around the cities of my country Ukraine have been evacuated to
a safe location and out of the country, most especially children with
their parents, nursing mothers and pregnant women, and those who have
been seriously wounded and need urgent medical attention. I was among
those that were able to evacuate to our neighbouring countries and I’m
now in the refugee camp of Ter Apel Groningen in the Netherlands.
I need a foreign partner to enable me to transport my investment
capital and then relocate with my family, honestly i wish I will
discuss more and get along. I need a partner because my investment
capital is in my international account. I’m interested in buying
properties, houses, building real estates, my capital for investment
is ($30 Million USD) . The financial institutions in my country
Ukraine are all shot down due to the crisis of this war on Ukraine
soil by the Russian forces. Meanwhile, if there is any profitable
investment that you have so much experience in your country, then we
can join together as partners since I’m a foreigner.
I came across your e-mail contact through private search while in need
of your assistance and I decided to contact you directly to ask you if
you know any lucrative business investment in your country i can
invest my money since my country Ukraine security and economic
independent has lost to the greatest lower level, and our culture has
lost including our happiness has been taken away from us. Our country
has been on fire for more than a year now.
If you are capable of handling this business partnership, contact me
for more details, I will appreciate it if you can contact me
immediately. You may as well tell me a little more about yourself.
Contact me urgently to enable us to proceed with the business. I will
be waiting for your response. My sincere apologies for the
inconvenience.
Thank you!
Mr. Razumkov Mykhailo.
From commit ebf7d1f508a73871 ("bpf, x64: rework pro/epilogue and tailcall
handling in JIT"), the tailcall on x64 works better than before.
From commit e411901c0b775a3a ("bpf: allow for tailcalls in BPF subprograms
for x64 JIT"), tailcall is able to run in BPF subprograms on x64.
From commit 5b92a28aae4dd0f8 ("bpf: Support attaching tracing BPF program
to other BPF programs"), BPF program is able to trace other BPF programs.
How about combining them all together?
1. FENTRY/FEXIT on a BPF subprogram.
2. A tailcall runs in the BPF subprogram.
3. The tailcall calls itself.
As a result, a tailcall infinite loop comes up. And the loop would halt
the machine.
As we know, in tail call context, the tail_call_cnt propagates by stack
and RAX register between BPF subprograms. So do it in FENTRY/FEXIT
trampolines.
How did I discover the bug?
From commit 7f6e4312e15a5c37 ("bpf: Limit caller's stack depth 256 for
subprogs with tailcalls"), the total stack size limits to around 8KiB.
Then, I write some bpf progs to validate the stack consuming, that are
tailcalls running in bpf2bpf and FENTRY/FEXIT tracing on bpf2bpf[1].
At that time, accidently, I made a tailcall loop. And then the loop halted
my VM. Without the loop, the bpf progs would consume over 8KiB stack size.
But the _stack-overflow_ did not halt my VM.
With bpf_printk(), I confirmed that the tailcall count limit did not work
expectedly. Next, read the code and fix it.
Finally, unfortunately, I only fix it on x64 but other arches. As a
result, CI tests failed because this bug hasn't been fixed on s390x.
Some helps are requested.
[1]: https://github.com/Asphaltt/learn-by-example/tree/main/ebpf/tailcall-stacko…
Leon Hwang (2):
bpf, x64: Fix tailcall infinite loop bug
selftests/bpf: Add testcases for tailcall infinite loop bug fixing
arch/x86/net/bpf_jit_comp.c | 23 ++-
include/linux/bpf.h | 6 +
kernel/bpf/trampoline.c | 5 +-
kernel/bpf/verifier.c | 9 +-
.../selftests/bpf/prog_tests/tailcalls.c | 194 +++++++++++++++++-
.../bpf/progs/tailcall_bpf2bpf_fentry.c | 18 ++
.../bpf/progs/tailcall_bpf2bpf_fexit.c | 18 ++
7 files changed, 264 insertions(+), 9 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fentry.c
create mode 100644 tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fexit.c
base-commit: 9930e4af4b509bcf6f060b09b16884f26102d110
--
2.41.0
The hwcaps selftest currently relies on the assembler being able to
assemble the crc32w instruction but this is not in the base v8.0 so is not
accepted by the standard GCC configurations used by many distributions.
Switch to manually encoding to fix the build.
Fixes: 09d2e95a04ad ("kselftest/arm64: add crc32 feature to hwcap test")
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
tools/testing/selftests/arm64/abi/hwcap.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/arm64/abi/hwcap.c b/tools/testing/selftests/arm64/abi/hwcap.c
index 112b6a219382..3b26a3660292 100644
--- a/tools/testing/selftests/arm64/abi/hwcap.c
+++ b/tools/testing/selftests/arm64/abi/hwcap.c
@@ -42,7 +42,8 @@ static void atomics_sigill(void)
static void crc32_sigill(void)
{
- asm volatile("crc32w w0, w0, w1");
+ /* CRC32W W0, W0, W1 */
+ asm volatile(".inst 0x1ac14800" : : : );
}
static void cssc_sigill(void)
---
base-commit: 358b763ee64b11f45287c286e1f6145729ed49ab
change-id: 20230816-arm64-fix-crc32-build-9d4c94f2e60e
Best regards,
--
Mark Brown <broonie(a)kernel.org>
lwt xmit hook does not expect positive return values in function
ip_finish_output2 and ip6_finish_output. However, BPF programs can
directly return positive statuses such like NET_XMIT_DROP, NET_RX_DROP,
and etc to the caller. Such return values would make the kernel continue
processing already freed skbs and eventually panic.
This set fixes the return values from BPF ops to unexpected continue
processing, checks strictly on the correct continue condition for
future proof. In addition, add missing selftests for BPF redirect
and reroute cases for BPF-CI.
v5: https://lore.kernel.org/bpf/cover.1692153515.git.yan@cloudflare.com/
v4: https://lore.kernel.org/bpf/ZMD1sFTW8SFiex+x@debian.debian/T/
v3: https://lore.kernel.org/bpf/cover.1690255889.git.yan@cloudflare.com/
v2: https://lore.kernel.org/netdev/ZLdY6JkWRccunvu0@debian.debian/
v1: https://lore.kernel.org/bpf/ZLbYdpWC8zt9EJtq@debian.debian/
changes since v5:
* fix BPF-CI failures due to missing config and busybox ping issue
changes since v4:
* fixed same error on BPF_REROUTE path
* re-implemented selftests under BPF-CI requirement
changes since v3:
* minor change in commit message and changelogs
* tested by Jakub Sitnicki
changes since v2:
* subject name changed
* also covered redirect to ingress case
* added selftests
changes since v1:
* minor code style changes
Yan Zhai (4):
lwt: fix return values of BPF xmit ops
lwt: check LWTUNNEL_XMIT_CONTINUE strictly
selftests/bpf: add lwt_xmit tests for BPF_REDIRECT
selftests/bpf: add lwt_xmit tests for BPF_REROUTE
include/net/lwtunnel.h | 5 +-
net/core/lwt_bpf.c | 7 +-
net/ipv4/ip_output.c | 2 +-
net/ipv6/ip6_output.c | 2 +-
tools/testing/selftests/bpf/config | 2 +
.../selftests/bpf/prog_tests/lwt_helpers.h | 139 ++++++++
.../selftests/bpf/prog_tests/lwt_redirect.c | 330 ++++++++++++++++++
.../selftests/bpf/prog_tests/lwt_reroute.c | 262 ++++++++++++++
.../selftests/bpf/progs/test_lwt_redirect.c | 90 +++++
.../selftests/bpf/progs/test_lwt_reroute.c | 36 ++
10 files changed, 868 insertions(+), 7 deletions(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/lwt_helpers.h
create mode 100644 tools/testing/selftests/bpf/prog_tests/lwt_redirect.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/lwt_reroute.c
create mode 100644 tools/testing/selftests/bpf/progs/test_lwt_redirect.c
create mode 100644 tools/testing/selftests/bpf/progs/test_lwt_reroute.c
--
2.30.2
