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 --- fs/quota/compat.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 fs/quota/compat.h (limited to 'fs/quota/compat.h') diff --git a/fs/quota/compat.h b/fs/quota/compat.h new file mode 100644 index 000000000..ef7d1e12d --- /dev/null +++ b/fs/quota/compat.h @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +struct compat_if_dqblk { + compat_u64 dqb_bhardlimit; + compat_u64 dqb_bsoftlimit; + compat_u64 dqb_curspace; + compat_u64 dqb_ihardlimit; + compat_u64 dqb_isoftlimit; + compat_u64 dqb_curinodes; + compat_u64 dqb_btime; + compat_u64 dqb_itime; + compat_uint_t dqb_valid; +}; + +struct compat_fs_qfilestat { + compat_u64 dqb_bhardlimit; + compat_u64 qfs_nblks; + compat_uint_t qfs_nextents; +}; + +struct compat_fs_quota_stat { + __s8 qs_version; + __u16 qs_flags; + __s8 qs_pad; + struct compat_fs_qfilestat qs_uquota; + struct compat_fs_qfilestat qs_gquota; + compat_uint_t qs_incoredqs; + compat_int_t qs_btimelimit; + compat_int_t qs_itimelimit; + compat_int_t qs_rtbtimelimit; + __u16 qs_bwarnlimit; + __u16 qs_iwarnlimit; +}; -- cgit v1.3.1