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/uapi/asm-generic/statfs.h | 84 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 include/uapi/asm-generic/statfs.h (limited to 'include/uapi/asm-generic/statfs.h') diff --git a/include/uapi/asm-generic/statfs.h b/include/uapi/asm-generic/statfs.h new file mode 100644 index 000000000..bd35c7619 --- /dev/null +++ b/include/uapi/asm-generic/statfs.h @@ -0,0 +1,84 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_GENERIC_STATFS_H +#define _UAPI_GENERIC_STATFS_H + +#include + + +/* + * Most 64-bit platforms use 'long', while most 32-bit platforms use '__u32'. + * Yes, they differ in signedness as well as size. + * Special cases can override it for themselves -- except for S390x, which + * is just a little too special for us. And MIPS, which I'm not touching + * with a 10' pole. + */ +#ifndef __statfs_word +#if __BITS_PER_LONG == 64 +#define __statfs_word __kernel_long_t +#else +#define __statfs_word __u32 +#endif +#endif + +struct statfs { + __statfs_word f_type; + __statfs_word f_bsize; + __statfs_word f_blocks; + __statfs_word f_bfree; + __statfs_word f_bavail; + __statfs_word f_files; + __statfs_word f_ffree; + __kernel_fsid_t f_fsid; + __statfs_word f_namelen; + __statfs_word f_frsize; + __statfs_word f_flags; + __statfs_word f_spare[4]; +}; + +/* + * ARM needs to avoid the 32-bit padding at the end, for consistency + * between EABI and OABI + */ +#ifndef ARCH_PACK_STATFS64 +#define ARCH_PACK_STATFS64 +#endif + +struct statfs64 { + __statfs_word f_type; + __statfs_word f_bsize; + __u64 f_blocks; + __u64 f_bfree; + __u64 f_bavail; + __u64 f_files; + __u64 f_ffree; + __kernel_fsid_t f_fsid; + __statfs_word f_namelen; + __statfs_word f_frsize; + __statfs_word f_flags; + __statfs_word f_spare[4]; +} ARCH_PACK_STATFS64; + +/* + * IA64 and x86_64 need to avoid the 32-bit padding at the end, + * to be compatible with the i386 ABI + */ +#ifndef ARCH_PACK_COMPAT_STATFS64 +#define ARCH_PACK_COMPAT_STATFS64 +#endif + +struct compat_statfs64 { + __u32 f_type; + __u32 f_bsize; + __u64 f_blocks; + __u64 f_bfree; + __u64 f_bavail; + __u64 f_files; + __u64 f_ffree; + __kernel_fsid_t f_fsid; + __u32 f_namelen; + __u32 f_frsize; + __u32 f_flags; + __u32 f_spare[4]; +} ARCH_PACK_COMPAT_STATFS64; + +#endif /* _UAPI_GENERIC_STATFS_H */ -- cgit v1.3.1