From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- include/asm-generic/resource.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 include/asm-generic/resource.h (limited to 'include/asm-generic/resource.h') diff --git a/include/asm-generic/resource.h b/include/asm-generic/resource.h new file mode 100644 index 000000000..8874f681b --- /dev/null +++ b/include/asm-generic/resource.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_RESOURCE_H +#define _ASM_GENERIC_RESOURCE_H + +#include + + +/* + * boot-time rlimit defaults for the init task: + */ +#define INIT_RLIMITS \ +{ \ + [RLIMIT_CPU] = { RLIM_INFINITY, RLIM_INFINITY }, \ + [RLIMIT_FSIZE] = { RLIM_INFINITY, RLIM_INFINITY }, \ + [RLIMIT_DATA] = { RLIM_INFINITY, RLIM_INFINITY }, \ + [RLIMIT_STACK] = { _STK_LIM, RLIM_INFINITY }, \ + [RLIMIT_CORE] = { 0, RLIM_INFINITY }, \ + [RLIMIT_RSS] = { RLIM_INFINITY, RLIM_INFINITY }, \ + [RLIMIT_NPROC] = { 0, 0 }, \ + [RLIMIT_NOFILE] = { INR_OPEN_CUR, INR_OPEN_MAX }, \ + [RLIMIT_MEMLOCK] = { MLOCK_LIMIT, MLOCK_LIMIT }, \ + [RLIMIT_AS] = { RLIM_INFINITY, RLIM_INFINITY }, \ + [RLIMIT_LOCKS] = { RLIM_INFINITY, RLIM_INFINITY }, \ + [RLIMIT_SIGPENDING] = { 0, 0 }, \ + [RLIMIT_MSGQUEUE] = { MQ_BYTES_MAX, MQ_BYTES_MAX }, \ + [RLIMIT_NICE] = { 0, 0 }, \ + [RLIMIT_RTPRIO] = { 0, 0 }, \ + [RLIMIT_RTTIME] = { RLIM_INFINITY, RLIM_INFINITY }, \ +} + +#endif -- cgit v1.3.1