]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
bpf: Check rcu_read_lock_trace_held() before calling bpf map helpers
authorHou Tao <houtao1@huawei.com>
Mon, 4 Dec 2023 14:04:19 +0000 (22:04 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 2 May 2025 05:44:21 +0000 (07:44 +0200)
commit3516f93cc63d956e1b290ae4b7bf2586074535a0
treeb318f7113957fba2e049b7c5a220d85a38a4f032
parent0d90d9e154144a3a80e9fc0eb9b21b7fc990f68f
bpf: Check rcu_read_lock_trace_held() before calling bpf map helpers

commit 169410eba271afc9f0fb476d996795aa26770c6d upstream.

These three bpf_map_{lookup,update,delete}_elem() helpers are also
available for sleepable bpf program, so add the corresponding lock
assertion for sleepable bpf program, otherwise the following warning
will be reported when a sleepable bpf program manipulates bpf map under
interpreter mode (aka bpf_jit_enable=0):

  WARNING: CPU: 3 PID: 4985 at kernel/bpf/helpers.c:40 ......
  CPU: 3 PID: 4985 Comm: test_progs Not tainted 6.6.0+ #2
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......
  RIP: 0010:bpf_map_lookup_elem+0x54/0x60
  ......
  Call Trace:
   <TASK>
   ? __warn+0xa5/0x240
   ? bpf_map_lookup_elem+0x54/0x60
   ? report_bug+0x1ba/0x1f0
   ? handle_bug+0x40/0x80
   ? exc_invalid_op+0x18/0x50
   ? asm_exc_invalid_op+0x1b/0x20
   ? __pfx_bpf_map_lookup_elem+0x10/0x10
   ? rcu_lockdep_current_cpu_online+0x65/0xb0
   ? rcu_is_watching+0x23/0x50
   ? bpf_map_lookup_elem+0x54/0x60
   ? __pfx_bpf_map_lookup_elem+0x10/0x10
   ___bpf_prog_run+0x513/0x3b70
   __bpf_prog_run32+0x9d/0xd0
   ? __bpf_prog_enter_sleepable_recur+0xad/0x120
   ? __bpf_prog_enter_sleepable_recur+0x3e/0x120
   bpf_trampoline_6442580665+0x4d/0x1000
   __x64_sys_getpgid+0x5/0x30
   ? do_syscall_64+0x36/0xb0
   entry_SYSCALL_64_after_hwframe+0x6e/0x76
   </TASK>

Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20231204140425.1480317-2-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Cliff Liu <donghua.liu@windriver.com>
Signed-off-by: He Zhe <Zhe.He@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/bpf/helpers.c