bpf: Move out synchronize_rcu_tasks_trace from mutex CS

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Commit ef1b808e3b ("bpf: Fix UAF via mismatching bpf_prog/attachment
RCU flavors") resolved a possible UAF issue in uprobes that attach
non-sleepable bpf prog by explicitly waiting for a tasks-trace-RCU grace
period. But, in the current implementation, synchronize_rcu_tasks_trace
is included within the mutex critical section, which increases the
length of the critical section and may affect performance. So let's move
out synchronize_rcu_tasks_trace from mutex CS.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20250104013946.1111785-1-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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Pu Lehui 2025-01-04 01:39:46 +00:00 • committed by Alexei Starovoitov

parent b8b1e30016

commit ca3c4f646a

1 changed files with 13 additions and 8 deletions

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kernel/trace/bpf_trace.c

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