Alexei Starovoitov acf1c3d68e bpf: Fix race between btf_put and btf_idr walk. ... Florian and Eduard reported hard dead lock: [ 58.433327] _raw_spin_lock_irqsave+0x40/0x50 [ 58.433334] btf_put+0x43/0x90 [ 58.433338] bpf_find_btf_id+0x157/0x240 [ 58.433353] btf_parse_fields+0x921/0x11c0 This happens since btf->refcount can be 1 at the time of btf_put() and btf_put() will call btf_free_id() which will try to grab btf_idr_lock and will dead lock. Avoid the issue by doing btf_put() without locking. Fixes: 3d78417b60 ("bpf: Add bpf_btf_find_by_name_kind() helper.") Fixes: 1e89106da2 ("bpf: Add bpf_core_add_cands() and wire it into bpf_core_apply_relo_insn().") Reported-by: Florian Westphal <fw@strlen.de> Reported-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20230421014901.70908-1-alexei.starovoitov@gmail.com		2023-04-21 16:27:56 +02:00
..
preload	bpf: iterators: Split iterators.lskel.h into little- and big- endian versions	2023-01-28 12:45:15 -08:00
arraymap.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
bloom_filter.c	bpf: compute hashes in bloom filter similar to hashmap	2023-04-02 08:44:49 -07:00
bpf_cgrp_storage.c	bpf: Teach verifier that certain helpers accept NULL pointer.	2023-04-04 16:57:16 -07:00
bpf_inode_storage.c	bpf: Teach verifier that certain helpers accept NULL pointer.	2023-04-04 16:57:16 -07:00
bpf_iter.c	bpf: implement numbers iterator	2023-03-08 16:19:51 -08:00
bpf_local_storage.c	bpf: Handle NULL in bpf_local_storage_free.	2023-04-12 10:27:50 -07:00
bpf_lru_list.c
bpf_lru_list.h	printk: stop including cache.h from printk.h	2022-05-13 07:20:07 -07:00
bpf_lsm.c	bpf: Fix the kernel crash caused by bpf_setsockopt().	2023-01-26 23:26:40 -08:00
bpf_struct_ops_types.h	bpf: Add dummy BPF STRUCT_OPS for test purpose	2021-11-01 14:10:00 -07:00
bpf_struct_ops.c	bpf: Check IS_ERR for the bpf_map_get() return value	2023-03-24 12:40:47 -07:00
bpf_task_storage.c	bpf: Teach verifier that certain helpers accept NULL pointer.	2023-04-04 16:57:16 -07:00
btf.c	bpf: Fix race between btf_put and btf_idr walk.	2023-04-21 16:27:56 +02:00
cgroup_iter.c	bpf: Pin the start cgroup in cgroup_iter_seq_init()	2022-11-21 17:40:42 +01:00
cgroup.c	bpf: allow ctx writes using BPF_ST_MEM instruction	2023-03-03 21:41:46 -08:00
core.c	bpf: Support 64-bit pointers to kfuncs	2023-04-13 21:36:41 -07:00
cpumap.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
cpumask.c	bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGS	2023-03-25 16:56:22 -07:00
devmap.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
disasm.c	bpf: Relicense disassembler as GPL-2.0-only OR BSD-2-Clause	2021-09-02 14:49:23 +02:00
disasm.h	bpf: Relicense disassembler as GPL-2.0-only OR BSD-2-Clause	2021-09-02 14:49:23 +02:00
dispatcher.c	bpf: Synchronize dispatcher update with bpf_dispatcher_xdp_func	2022-12-14 12:02:14 -08:00
hashtab.c	bpf: optimize hashmap lookups when key_size is divisible by 4	2023-04-01 15:08:19 -07:00
helpers.c	bpf: Centralize btf_field-specific initialization logic	2023-04-15 17:36:50 -07:00
inode.c	fs: port inode_init_owner() to mnt_idmap	2023-01-19 09:24:28 +01:00
Kconfig	rcu: Make the TASKS_RCU Kconfig option be selected	2022-04-20 16:52:58 -07:00
link_iter.c	bpf: Add bpf_link iterator	2022-05-10 11:20:45 -07:00
local_storage.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
log.c	bpf: Relax log_buf NULL conditions when log_level>0 is requested	2023-04-11 18:05:44 +02:00
lpm_trie.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
Makefile	bpf: Split off basic BPF verifier log into separate file	2023-04-11 18:05:42 +02:00
map_in_map.c	bpf: Remove btf_field_offs, use btf_record's fields instead	2023-04-15 17:36:49 -07:00
map_in_map.h
map_iter.c	bpf: Introduce MEM_RDONLY flag	2021-12-18 13:27:41 -08:00
memalloc.c	bpf: Add a few bpf mem allocator functions	2023-03-25 19:52:51 -07:00
mmap_unlock_work.h	bpf: Introduce helper bpf_find_vma	2021-11-07 11:54:51 -08:00
net_namespace.c	net: Add includes masked by netdevice.h including uapi/bpf.h	2021-12-29 20:03:05 -08:00
offload.c	bpf: offload map memory usage	2023-03-07 09:33:43 -08:00
percpu_freelist.c	bpf: Initialize same number of free nodes for each pcpu_freelist	2022-11-11 12:05:14 -08:00
percpu_freelist.h
prog_iter.c
queue_stack_maps.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
reuseport_array.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
ringbuf.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
stackmap.c	bpf: return long from bpf_map_ops funcs	2023-03-22 15:11:30 -07:00
syscall.c	bpf: lirc program type should not require SYS_CAP_ADMIN	2023-04-17 13:21:14 -07:00
sysfs_btf.c
task_iter.c	bpf: keep a reference to the mm, in case the task is dead.	2022-12-28 14:11:48 -08:00
tnum.c	bpf, tnums: Provably sound, faster, and more precise algorithm for tnum_mul	2021-06-01 13:34:15 +02:00
trampoline.c	bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modules	2023-03-15 18:38:21 -07:00
verifier.c	bpf: Improve verifier u32 scalar equality checking	2023-04-17 15:50:02 -07:00