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| author | Lucas De Marchi <lucas.demarchi@intel.com> | 2024-01-22 15:10:10 -0800 |
|---|---|---|
| committer | Lucas De Marchi <lucas.demarchi@intel.com> | 2024-01-22 15:10:10 -0800 |
| commit | be3382ecdf317f005e7d47356d0a9256cc36dd88 (patch) | |
| tree | 40ee42db6c5c510d998c23696a27254f22289094 /kernel/bpf/stackmap.c | |
| parent | f6bf0424cadc27d7cf6a049d2db960e4b52fa513 (diff) | |
| parent | 6613476e225e090cc9aad49be7fa504e290dd33d (diff) | |
Merge drm/drm-next into drm-xe-next
Sync to v6.8-rc1.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Diffstat (limited to 'kernel/bpf/stackmap.c')
| -rw-r--r-- | kernel/bpf/stackmap.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index d6b277482085..dff7ba539701 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -388,6 +388,7 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, { u32 trace_nr, copy_len, elem_size, num_elem, max_depth; bool user_build_id = flags & BPF_F_USER_BUILD_ID; + bool crosstask = task && task != current; u32 skip = flags & BPF_F_SKIP_FIELD_MASK; bool user = flags & BPF_F_USER_STACK; struct perf_callchain_entry *trace; @@ -410,6 +411,14 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, if (task && user && !user_mode(regs)) goto err_fault; + /* get_perf_callchain does not support crosstask user stack walking + * but returns an empty stack instead of NULL. + */ + if (crosstask && user) { + err = -EOPNOTSUPP; + goto clear; + } + num_elem = size / elem_size; max_depth = num_elem + skip; if (sysctl_perf_event_max_stack < max_depth) @@ -421,7 +430,7 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, trace = get_callchain_entry_for_task(task, max_depth); else trace = get_perf_callchain(regs, 0, kernel, user, max_depth, - false, false); + crosstask, false); if (unlikely(!trace)) goto err_fault; |