Eduard Zingerman <eddyz87@xxxxxxxxx> wrote: > > BUG: KASAN: slab-out-of-bounds in bpf_refcount_acquire_impl+0x63/0xd0 > > Write of size 4 at addr ffff8881072b34e8 by task new_name/12847 > > > > CPU: 1 PID: 12847 Comm: new_name Not tainted 6.3.0-rc6+ #129 > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-20220807_005459-localhost 04/01/2014 > > Call Trace: > > <TASK> > > dump_stack_lvl+0x32/0x40 > > print_address_description.constprop.0+0x2b/0x3d0 > > ? bpf_refcount_acquire_impl+0x63/0xd0 > > print_report+0xb0/0x260 > > ? bpf_refcount_acquire_impl+0x63/0xd0 > > ? kasan_addr_to_slab+0x9/0x70 > > ? bpf_refcount_acquire_impl+0x63/0xd0 > > kasan_report+0xad/0xd0 > > ? bpf_refcount_acquire_impl+0x63/0xd0 > > kasan_check_range+0x13b/0x190 > > bpf_refcount_acquire_impl+0x63/0xd0 > > bpf_prog_affcc6c9d58016ca___insert_in_tree_and_list+0x54/0x131 > > bpf_prog_795203cdef4805f4_insert_and_remove_tree_true_list_true+0x15/0x11b > > bpf_test_run+0x2a0/0x5f0 > > ? bpf_test_timer_continue+0x430/0x430 > > ? kmem_cache_alloc+0xe5/0x260 > > ? kasan_set_track+0x21/0x30 > > ? krealloc+0x9e/0xe0 > > bpf_prog_test_run_skb+0x890/0x1270 > > ? __kmem_cache_free+0x9f/0x170 > > ? bpf_prog_test_run_raw_tp+0x570/0x570 > > ? __fget_light+0x52/0x4d0 > > ? map_update_elem+0x680/0x680 > > __sys_bpf+0x75e/0xd10 > > ? bpf_link_by_id+0xa0/0xa0 > > ? rseq_get_rseq_cs+0x67/0x650 > > ? __blkcg_punt_bio_submit+0x1b0/0x1b0 > > __x64_sys_bpf+0x6f/0xb0 > > do_syscall_64+0x3a/0x80 > > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > RIP: 0033:0x7f2f6a8b392d > > Code: 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d d3 e4 0c 00 f7 d8 64 89 01 48 > > RSP: 002b:00007ffe46938328 EFLAGS: 00000206 ORIG_RAX: 0000000000000141 > > RAX: ffffffffffffffda RBX: 0000000007150690 RCX: 00007f2f6a8b392d > > RDX: 0000000000000050 RSI: 00007ffe46938360 RDI: 000000000000000a > > RBP: 00007ffe46938340 R08: 0000000000000064 R09: 00007ffe46938360 > > R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 > > R13: 00007ffe46938b78 R14: 0000000000e09db0 R15: 00007f2f6a9ff000 > > </TASK> > > > > I can also reproduce this on bpf-next/780c69830ec6b27e0224586ce26bc89552fcf163. > > Is this a known bug? > > Hi Florian, > > Thank you for the report, that's my bug :( > > After the suggested change I can run the ./test_progs till the end > (takes a few minutes, though). One test is failing: verifier_array_access, > this is because map it uses is not populated with values (as it was when this was > a part ./test_verifier). Right, I see that failure too. > However, in the middle of execution I do see a trace similar to yours: I see this as well, to get to it quicker: ./test_progs --allow=refcounted_kptr > [ 82.757127] ------------[ cut here ]------------ > [ 82.757667] refcount_t: saturated; leaking memory. > [ 82.758098] WARNING: CPU: 0 PID: 176 at lib/refcount.c:22 refcount_warn_saturate+0x61/0xe0 I get this one right after the kasan splat. > Could you please share your config? > I'd like to reproduce the hang. It hangs for me if I just rerun ./test_progs --allow=refcounted_kptr a couple of times (maybe once per cpu...?). I'll send the config if that doesn't hang for you.
