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| author | Martin KaFai Lau <martin.lau@kernel.org> | 2022-10-25 20:45:20 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-10-26 08:11:46 +0200 |
| commit | 4279adb094a17132423f1271c3d11b593fc2327e (patch) | |
| tree | 0601ed0271392f68e41f4672f63565bf27df3989 /kernel/trace | |
| parent | bpf: Avoid taking spinlock in bpf_task_storage_get if potential deadlock is d... (diff) | |
| download | linux-4279adb094a17132423f1271c3d11b593fc2327e.tar.xz linux-4279adb094a17132423f1271c3d11b593fc2327e.zip | |
bpf: Add new bpf_task_storage_get proto with no deadlock detection
The bpf_lsm and bpf_iter do not recur that will cause a deadlock.
The situation is similar to the bpf_pid_task_storage_lookup_elem()
which is called from the syscall map_lookup_elem. It does not need
deadlock detection. Otherwise, it will cause unnecessary failure
when calling the bpf_task_storage_get() helper.
This patch adds bpf_task_storage_get proto that does not do deadlock
detection. It will be used by bpf_lsm and bpf_iter programs.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20221025184524.3526117-6-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 83b9b9afe235..e9759b0f7199 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -6,6 +6,7 @@ #include <linux/types.h> #include <linux/slab.h> #include <linux/bpf.h> +#include <linux/bpf_verifier.h> #include <linux/bpf_perf_event.h> #include <linux/btf.h> #include <linux/filter.h> @@ -1488,7 +1489,9 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_this_cpu_ptr: return &bpf_this_cpu_ptr_proto; case BPF_FUNC_task_storage_get: - return &bpf_task_storage_get_recur_proto; + if (bpf_prog_check_recur(prog)) + return &bpf_task_storage_get_recur_proto; + return &bpf_task_storage_get_proto; case BPF_FUNC_task_storage_delete: return &bpf_task_storage_delete_recur_proto; case BPF_FUNC_for_each_map_elem: |