linux/kernel
Kaitao Cheng 4a7910ee06 bpf: Clear rb node linkage when freeing bpf_rb_root
bpf_rb_root_free() detaches the root by copying the current rb_root_cached
and then replacing the live root with RB_ROOT_CACHED. It then walks the
copied root and drops each object contained in the tree.

This leaves the rb node state intact while dropping the object. If the
object is refcounted and survives the drop, its bpf_rb_node_kern still
contains an owner pointer to the freed root and stale rb tree linkage. If
a later bpf_rb_root allocation reuses the same address, bpf_rbtree_remove()
can incorrectly pass the owner check and call rb_erase_cached() on a node
whose rb pointers belong to the old tree.

Mirror the list draining behavior by marking nodes as busy while the root
is being detached, then clear the rb node and release the owner before
dropping the containing object. This makes surviving nodes unowned and
safe to reject from remove or accept for a later add.

Fixes: 9c395c1b99 ("bpf: Add basic bpf_rb_{root,node} support")
Signed-off-by: Kaitao Cheng <chengkaitao@kylinos.cn>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20260605094143.5509-1-kaitao.cheng@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-05 14:19:19 -07:00
..
bpf bpf: Clear rb node linkage when freeing bpf_rb_root 2026-06-05 14:19:19 -07:00
cgroup cgroup: Fixes for v7.1-rc4 2026-05-22 16:28:47 -07:00
configs Remove WARN_ALL_UNSEEDED_RANDOM kernel config option 2026-02-23 11:18:48 -08:00
debug kgdb: update outdated references to kgdb_wait() 2026-04-21 16:41:54 +01:00
dma dma-mapping: move dma_map_resource() sanity check into debug code 2026-05-18 09:04:59 +02:00
entry arm64 updates for 7.1: 2026-04-14 16:48:56 -07:00
events Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 7.1-rc3 2026-05-10 13:24:49 -07:00
futex futex: Prevent lockup in requeue-PI during signal/ timeout wakeup 2026-04-29 08:56:40 +02:00
gcov Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
irq genirq/chip: Don't call add_interrupt_randomness() for NMIs 2026-05-11 14:56:04 +02:00
kcsan kcsan: test: Adjust "expect" allocation type for kmalloc_obj 2026-02-26 09:54:08 -08:00
livepatch Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
liveupdate liveupdate fixes for v7.1-rc4 2026-05-13 08:24:50 -07:00
locking locking/mutex: Fix ww_mutex wait_list operations 2026-04-23 10:05:49 +02:00
module module: Simplify warning on positive returns from module_init() 2026-04-04 00:04:48 +00:00
power Merge branches 'pm-cpuidle', 'pm-opp' and 'pm-sleep' 2026-04-10 12:37:27 +02:00
printk Merge branch 'rework/prb-fixes' into for-linus 2026-04-20 13:42:01 +02:00
rcu srcu: Don't queue workqueue handlers to never-online CPUs 2026-05-18 12:27:18 -07:00
sched sched_ext: Fixes for v7.1-rc4 2026-05-22 16:43:33 -07:00
time timers/migration: Fix another hotplug activation race 2026-05-06 08:21:12 +02:00
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 7.1-rc5 2026-05-25 06:33:30 -07:00
unwind Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
.gitignore
acct.c vfs-7.1-rc1.misc 2026-04-13 14:20:11 -07:00
async.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
audit_fsnotify.c audit: widen ino fields to u64 2026-03-06 14:31:26 +01:00
audit_tree.c Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
audit_watch.c audit: widen ino fields to u64 2026-03-06 14:31:26 +01:00
audit.c audit: enforce AUDIT_LOCKED for AUDIT_TRIM and AUDIT_MAKE_EQUIV 2026-05-12 16:10:38 -04:00
audit.h audit: widen ino fields to u64 2026-03-06 14:31:26 +01:00
auditfilter.c audit: fix coding style issues 2026-03-05 22:16:08 -05:00
auditsc.c audit: fix incorrect inheritable capability in CAPSET records 2026-05-12 16:05:57 -04:00
backtracetest.c
bounds.c x86/asm: Remove ANNOTATE_DATA_SPECIAL usage 2025-12-03 16:53:19 +01:00
capability.c
cfi.c
compat.c
configs.c
context_tracking.c context_tracking: Remove rcu_task_trace_heavyweight_{enter,exit}() 2026-01-01 16:39:46 +08:00
cpu_pm.c
cpu.c SPDX updates for 7.0-rc1 2026-02-17 09:46:03 -08:00
crash_core_test.c
crash_core.c kernel/crash: remove inclusion of crypto/sha1.h 2026-03-27 21:19:46 -07:00
crash_dump_dm_crypt.c crash_dump/dm-crypt: don't print in arch-specific code 2026-04-02 23:36:24 -07:00
crash_reserve.c kernel/crash: remove inclusion of crypto/sha1.h 2026-03-27 21:19:46 -07:00
cred.c cred: remove unused set_security_override_from_ctx() 2026-01-06 20:52:57 -05:00
delayacct.c delayacct: fix uapi timespec64 definition 2026-02-08 00:13:32 -08:00
dma.c
elfcorehdr.c
exec_domain.c
exit.c ptrace: slightly saner 'get_dumpable()' logic 2026-05-14 08:32:11 -07:00
exit.h
extable.c
fail_function.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
fork.c futex: Drop CLONE_THREAD requirement for private default hash alloc 2026-05-01 13:12:34 -07:00
freezer.c
gen_kheaders.sh
groups.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
hung_task.c hung_task: explicitly report I/O wait state in log output 2026-03-27 21:19:40 -07:00
iomem.c
irq_work.c irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT 2026-05-11 16:28:04 +02:00
jump_label.c jump_label: use ATOMIC_INIT() for initialization of .enabled 2026-03-16 13:16:48 +01:00
kallsyms_internal.h kallsyms: Get rid of kallsyms relative base 2026-01-22 15:58:22 -07:00
kallsyms_selftest.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kallsyms_selftest.h
kallsyms.c mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.kexec
Kconfig.locks
Kconfig.preempt sched: Further restrict the preemption modes 2026-01-08 12:43:57 +01:00
kcov.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kexec_core.c kernel/kexec: remove inclusion of crypto/hash.h 2026-03-27 21:19:46 -07:00
kexec_elf.c
kexec_file.c kexec: derive purgatory entry from symbol 2026-01-31 16:16:07 -08:00
kexec_internal.h
kexec.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kheaders.c
kprobes.c kprobes: Remove unneeded warnings from __arm_kprobe_ftrace() 2026-03-13 23:15:26 +09:00
kstack_erase.c
ksyms_common.c
ksysfs.c kernel: ksysfs: initialize kernel_kobj earlier 2026-04-03 19:39:52 +02:00
kthread.c kthread: consolidate kthread exit paths to prevent use-after-free 2026-02-26 10:45:49 +01:00
latencytop.c
Makefile kcov: Enable context analysis 2026-01-05 16:43:34 +01:00
module_signature.c module: Give 'enum pkey_id_type' a more specific name 2026-03-24 21:42:37 +00:00
notifier.c
nscommon.c nsfs: tighten permission checks for ns iteration ioctls 2026-02-27 22:00:08 +01:00
nsproxy.c vfs-7.1-rc1.mount.v2 2026-04-14 19:59:25 -07:00
nstree.c nstree: tighten permission checks for listing 2026-02-27 22:00:11 +01:00
padata.c padata: Put CPU offline callback in ONLINE section to allow failure 2026-03-22 11:17:59 +09:00
panic.c kernel/panic: mark init_taint_buf as __initdata and panic instead of warning in alloc_taint_buf() 2026-03-27 21:19:33 -07:00
params.c module: Clean up parse_args() arguments 2026-03-18 21:43:18 +00:00
pid_namespace.c pid_namespace: allow opening pid_for_children before init was created 2026-03-20 14:44:26 +01:00
pid_sysctl.h
pid.c mm.git review status for linus..mm-nonmm-stable 2026-04-16 20:11:56 -07:00
profile.c
ptrace.c ptrace: slightly saner 'get_dumpable()' logic 2026-05-14 08:32:11 -07:00
range.c
reboot.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
regset.c
relay.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
resource_kunit.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
resource.c PCI: Align head space better 2026-03-27 10:19:08 -05:00
rseq.c rseq: Reenable performance optimizations conditionally 2026-05-06 17:40:27 +02:00
scftorture.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
scs.c
seccomp.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
signal.c mm.git review status for linus..mm-nonmm-stable 2026-04-16 20:11:56 -07:00
smp.c tracing updates for v7.1: 2026-04-17 09:43:12 -07:00
smpboot.c
smpboot.h
softirq.c softirq: Prepare for deferred hrtimer rearming 2026-02-27 16:40:13 +01:00
stacktrace.c
static_call_inline.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
static_call.c
stop_machine.c
sys_ni.c rseq: Implement sys_rseq_slice_yield() 2026-01-22 11:11:17 +01:00
sys.c prctl: cfi: change the branch landing pad prctl()s to be more descriptive 2026-04-04 18:40:58 -06:00
sysctl-test.c
sysctl.c sysctl: fix uninitialized variable in proc_do_large_bitmap 2026-03-26 09:32:19 +01:00
task_work.c
taskstats.c taskstats: set version in TGID exit notifications 2026-04-15 02:15:02 -07:00
torture.c torture: Avoid modulo-zero error in torture_hrtimeout_ns() 2026-03-30 15:48:14 -04:00
tracepoint.c tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func() 2026-04-14 05:17:02 -04:00
tsacct.c tsacct: skip all kernel threads 2026-01-26 19:07:13 -08:00
ucount.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
uid16.c
uid16.h
umh.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
up.c
user_namespace.c Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
vhost_task.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
vmcore_info.c mm.git review status for linus..mm-nonmm-stable 2026-04-16 20:11:56 -07:00
watch_queue.c Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
watchdog_buddy.c watchdog/hardlockup: improve buddy system detection timeliness 2026-03-27 21:19:47 -07:00
watchdog_perf.c watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency 2026-02-08 00:13:35 -08:00
watchdog.c watchdog/hardlockup: improve buddy system detection timeliness 2026-03-27 21:19:47 -07:00
workqueue_internal.h workqueue: Show in-flight work item duration in stall diagnostics 2026-03-05 07:27:48 -10:00
workqueue.c workqueue: Fix wq->cpu_pwq leak in alloc_and_link_pwqs() WQ_UNBOUND path 2026-05-08 07:59:44 -10:00