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 --- arch/m68k/sun3/intersil.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 arch/m68k/sun3/intersil.c (limited to 'arch/m68k/sun3/intersil.c') diff --git a/arch/m68k/sun3/intersil.c b/arch/m68k/sun3/intersil.c new file mode 100644 index 000000000..29674cfa9 --- /dev/null +++ b/arch/m68k/sun3/intersil.c @@ -0,0 +1,70 @@ +/* + * arch/m68k/sun3/intersil.c + * + * basic routines for accessing the intersil clock within the sun3 machines + * + * started 11/12/1999 Sam Creasey + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +#include +#include + +#include +#include +#include + +#include "sun3.h" + +/* bits to set for start/run of the intersil */ +#define STOP_VAL (INTERSIL_STOP | INTERSIL_INT_ENABLE | INTERSIL_24H_MODE) +#define START_VAL (INTERSIL_RUN | INTERSIL_INT_ENABLE | INTERSIL_24H_MODE) + +/* get/set hwclock */ + +int sun3_hwclk(int set, struct rtc_time *t) +{ + volatile struct intersil_dt *todintersil; + unsigned long flags; + + todintersil = (struct intersil_dt *) &intersil_clock->counter; + + local_irq_save(flags); + + intersil_clock->cmd_reg = STOP_VAL; + + /* set or read the clock */ + if(set) { + todintersil->csec = 0; + todintersil->hour = t->tm_hour; + todintersil->minute = t->tm_min; + todintersil->second = t->tm_sec; + todintersil->month = t->tm_mon + 1; + todintersil->day = t->tm_mday; + todintersil->year = (t->tm_year - 68) % 100; + todintersil->weekday = t->tm_wday; + } else { + /* read clock */ + t->tm_sec = todintersil->csec; + t->tm_hour = todintersil->hour; + t->tm_min = todintersil->minute; + t->tm_sec = todintersil->second; + t->tm_mon = todintersil->month - 1; + t->tm_mday = todintersil->day; + t->tm_year = todintersil->year + 68; + t->tm_wday = todintersil->weekday; + if (t->tm_year < 70) + t->tm_year += 100; + } + + intersil_clock->cmd_reg = START_VAL; + + local_irq_restore(flags); + + return 0; + +} + -- cgit v1.3.1