diff options
| author | Vincent Donnefort <vdonnefort@google.com> | 2026-07-09 17:00:16 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-07-10 14:04:26 -0400 |
| commit | d471d4f86e8689ad15309e49da8e5e4e9bb9ce87 (patch) | |
| tree | aa31951f43c640f190372eb59f48d129d547284d /kernel/trace | |
| parent | ec082d0b978b5fb4c11205ccce63587ac94c74e1 (diff) | |
tracing/remotes: Fix struct_len in trace_remote_alloc_buffer()
Pre-calculate desc->struct_len up-front in trace_remote_alloc_buffer()
with trace_buffer_desc_size() to fix double-counting.
While at it, use the accessor __first_ring_buffer_desc().
Link: https://patch.msgid.link/20260709160017.1729517-3-vdonnefort@google.com
Fixes: 96e43537af54 ("tracing: Introduce trace remotes")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_remote.c | 15 |
1 files changed, 4 insertions, 11 deletions
diff --git a/kernel/trace/trace_remote.c b/kernel/trace/trace_remote.c index d48042239d58..0f6ef5c36d84 100644 --- a/kernel/trace/trace_remote.c +++ b/kernel/trace/trace_remote.c @@ -979,27 +979,22 @@ EXPORT_SYMBOL_GPL(trace_remote_free_buffer); int trace_remote_alloc_buffer(struct trace_buffer_desc *desc, size_t desc_size, size_t buffer_size, const struct cpumask *cpumask) { + size_t min_desc_size = trace_buffer_desc_size(buffer_size, cpumask_weight(cpumask)); unsigned int nr_pages = max(DIV_ROUND_UP(buffer_size, PAGE_SIZE), 2UL) + 1; - void *desc_end = desc + desc_size; struct ring_buffer_desc *rb_desc; int cpu, ret = -ENOMEM; - if (desc_size < struct_size(desc, __data, 0)) + if (desc_size < min_desc_size) return -EINVAL; desc->nr_cpus = 0; - desc->struct_len = struct_size(desc, __data, 0); + desc->struct_len = min_desc_size; - rb_desc = (struct ring_buffer_desc *)&desc->__data[0]; + rb_desc = __first_ring_buffer_desc(desc); for_each_cpu(cpu, cpumask) { unsigned int id; - if ((void *)rb_desc + struct_size(rb_desc, page_va, nr_pages) > desc_end) { - ret = -EINVAL; - goto err; - } - rb_desc->cpu = cpu; rb_desc->nr_page_va = 0; rb_desc->meta_va = (unsigned long)__get_free_page(GFP_KERNEL); @@ -1015,8 +1010,6 @@ int trace_remote_alloc_buffer(struct trace_buffer_desc *desc, size_t desc_size, rb_desc->nr_page_va++; } - desc->struct_len += offsetof(struct ring_buffer_desc, page_va); - desc->struct_len += struct_size(rb_desc, page_va, rb_desc->nr_page_va); rb_desc = __next_ring_buffer_desc(rb_desc); } |