tracing: Bound histogram expression strings with seq_buf

Browse source

expr_str() allocates a fixed MAX_FILTER_STR_VAL buffer and then builds
expression names with a series of raw strcat() appends. Nested operands,
constants, field flags, and generated field names can push the rendered
string past that fixed limit before the name is attached to the hist
field.

Build expression strings with seq_buf and return -E2BIG when the
rendered name would exceed MAX_FILTER_STR_VAL. This keeps the existing
tracing-side limit while replacing the raw append logic with bounded
construction.

Link: https://patch.msgid.link/20260611055945.22348-4-pengpeng@iscas.ac.cn
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

...

This commit is contained in:

Pengpeng Hou 2026-06-11 13:59:45 +08:00 • committed by Steven Rostedt

parent a5ca27e8ff

commit 935601a427

1 changed files with 33 additions and 24 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

57

kernel/trace/trace_events_hist.c

View file