diff options
| author | Jose Fernandez (Anthropic) <jose.fernandez@linux.dev> | 2026-09-24 22:35:46 +0000 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-10-19 10:28:11 -0400 |
| commit | c738829502be3f71500b9e70e04f8eee49734d95 (patch) | |
| tree | f0f96070308a8128edba87c0932629bf92c39a37 /kernel/trace | |
| parent | 6703ab347f4b7c228bbe391dafbe57b1a62b2997 (diff) | |
ftrace: Let ftrace_call_adjust() reject a patch site
When ftrace_call_adjust() returns 0 for a patch site,
ftrace_process_locs() does not skip the site. The NULL test runs before
the adjustment since commit 6eeca746fa5f ("ftrace: Test mcount_loc
addr before calling ftrace_call_addr()"), so the 0 is stored as the
record's ip and ftrace_init_nop() later hits the BUG_ON() in arm64's
patch_map(). Test the adjusted address too and count the site as
skipped.
Link: https://patch.msgid.link/20260924-b4-arm64-callops-kcfi-v2-2-587865b6d991@linux.dev
Reviewed-by: Ben Cressey <ben@cressey.dev>
Reviewed-by: Florent Revest (Anthropic) <florent.revest@linux.dev>
Assisted-by: LLM
Signed-off-by: Jose Fernandez (Anthropic) <jose.fernandez@linux.dev>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/ftrace.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index c8f8dd1cb92f..b2597eb9581b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7707,6 +7707,11 @@ static int ftrace_process_locs(struct module *mod, } addr = ftrace_call_adjust(addr); + /* The architecture may return 0 to reject a patch site */ + if (!addr) { + skipped++; + continue; + } end_offset = (pg->index+1) * sizeof(pg->records[0]); if (end_offset > PAGE_SIZE << pg->order) { |