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/lockd/Makefile | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 fs/lockd/Makefile (limited to 'fs/lockd/Makefile') diff --git a/fs/lockd/Makefile b/fs/lockd/Makefile new file mode 100644 index 000000000..3f9569d3b --- /dev/null +++ b/fs/lockd/Makefile @@ -0,0 +1,52 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the linux lock manager stuff +# + +ccflags-y += -I$(src) # needed for trace events + +obj-$(CONFIG_LOCKD) += lockd.o + +lockd-y := clntlock.o clntproc.o clntxdr.o host.o svc.o svclock.o \ + svcshare.o svcproc.o svcsubs.o mon.o trace.o netlink.o \ + nlm3xdr_gen.o +lockd-$(CONFIG_LOCKD_V4) += clnt4xdr.o svc4proc.o nlm4xdr_gen.o +lockd-$(CONFIG_PROC_FS) += procfs.o + +# +# XDR code generation (requires Python and additional packages) +# +# The generated *xdr_gen.{h,c} files are checked into git. Normal kernel +# builds do not require the xdrgen tool or its Python dependencies. +# +# Developers modifying .x files in Documentation/sunrpc/xdr/ should run +# "make xdrgen" to regenerate the affected files. +# +.PHONY: xdrgen + +XDRGEN = ../../tools/net/sunrpc/xdrgen/xdrgen + +XDRGEN_DEFINITIONS = ../../include/linux/sunrpc/xdrgen/nlm4.h \ + ../../include/linux/sunrpc/xdrgen/nlm3.h +XDRGEN_DECLARATIONS = nlm4xdr_gen.h nlm3xdr_gen.h +XDRGEN_SOURCE = nlm4xdr_gen.c nlm3xdr_gen.c + +xdrgen: $(XDRGEN_DEFINITIONS) $(XDRGEN_DECLARATIONS) $(XDRGEN_SOURCE) + +../../include/linux/sunrpc/xdrgen/nlm4.h: ../../Documentation/sunrpc/xdr/nlm4.x + $(XDRGEN) definitions $< > $@ + +../../include/linux/sunrpc/xdrgen/nlm3.h: ../../Documentation/sunrpc/xdr/nlm3.x + $(XDRGEN) definitions $< > $@ + +nlm4xdr_gen.h: ../../Documentation/sunrpc/xdr/nlm4.x + $(XDRGEN) declarations $< > $@ + +nlm3xdr_gen.h: ../../Documentation/sunrpc/xdr/nlm3.x + $(XDRGEN) declarations $< > $@ + +nlm4xdr_gen.c: ../../Documentation/sunrpc/xdr/nlm4.x + $(XDRGEN) source --peer server $< > $@ + +nlm3xdr_gen.c: ../../Documentation/sunrpc/xdr/nlm3.x + $(XDRGEN) source --peer server $< > $@ -- cgit v1.3.1