linux/include/trace
Steven Rostedt (Google) 24f5bb9f24 tracing: Just use strcmp() for testing __string() and __assign_str() match
As __assign_str() no longer uses its "src" parameter, there's a check to
make sure nothing depends on it being different than what was passed to
__string(). It originally just compared the pointer passed to __string()
with the pointer passed into __assign_str() via the "src" parameter. But
there's a couple of outliers that just pass in a quoted string constant,
where comparing the pointers is UB to the compiler, as the compiler is
free to create multiple copies of the same string constant.

Instead, just use strcmp(). It may slow down the trace event, but this
will eventually be removed.

Also, fix the issue of passing NULL to strcmp() by adding a WARN_ON() to
make sure that both "src" and the pointer saved in __string() are either
both NULL or have content, and then checking if "src" is not NULL before
performing the strcmp().

Link: https://lore.kernel.org/all/CAHk-=wjxX16kWd=uxG5wzqt=aXoYDf1BgWOKk+qVmAO0zh7sjA@mail.gmail.com/

Fixes: b1afefa62c ("tracing: Use strcmp() in __assign_str() WARN_ON() check")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-03-19 11:23:30 -07:00
..
events Tracing updates for 6.9: 2024-03-18 15:11:44 -07:00
misc NFS client updates for Linux 6.9 2024-03-16 11:44:00 -07:00
stages tracing: Just use strcmp() for testing __string() and __assign_str() match 2024-03-19 11:23:30 -07:00
bpf_probe.h kernel.h: split out COUNT_ARGS() and CONCATENATE() to args.h 2023-08-18 10:18:56 -07:00
define_custom_trace.h tracing: Add TRACE_CUSTOM_EVENT() macro 2022-03-11 11:49:24 -05:00
define_trace.h
perf.h perf/tracing: Use stage6 of tracing to not duplicate macros 2023-01-25 10:31:24 -05:00
syscall.h
trace_custom_events.h tracing: Rename the staging files for trace_events 2022-04-02 08:40:04 -04:00
trace_events.h tracing: Rename the staging files for trace_events 2022-04-02 08:40:04 -04:00