From: Masami Hiramatsu (Google) <mhira...@kernel.org> Allocate temporary string buffers for fprobe-event from heap instead of stack. This fixes the stack frame exceed limit error.
Reported-by: kernel test robot <l...@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202506240416.nzihdxoo-...@intel.com/ Signed-off-by: Masami Hiramatsu (Google) <mhira...@kernel.org> --- kernel/trace/trace_fprobe.c | 39 ++++++++++++++++++++++++++------------- 1 file changed, 26 insertions(+), 13 deletions(-) diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 264cf7fc9a1d..fd1036e27309 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -1234,18 +1234,18 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], * FETCHARG:TYPE : use TYPE instead of unsigned long. */ struct trace_fprobe *tf __free(free_trace_fprobe) = NULL; - struct module *mod __free(module_put) = NULL; - int i, new_argc = 0, ret = 0; - bool is_return = false; - char *symbol __free(kfree) = NULL; const char *event = NULL, *group = FPROBE_EVENT_SYSTEM; + struct module *mod __free(module_put) = NULL; const char **new_argv __free(kfree) = NULL; - char buf[MAX_EVENT_NAME_LEN]; - char gbuf[MAX_EVENT_NAME_LEN]; - char sbuf[KSYM_NAME_LEN]; - char abuf[MAX_BTF_ARGS_LEN]; + char *symbol __free(kfree) = NULL; + char *ebuf __free(kfree) = NULL; + char *gbuf __free(kfree) = NULL; + char *sbuf __free(kfree) = NULL; + char *abuf __free(kfree) = NULL; char *dbuf __free(kfree) = NULL; + int i, new_argc = 0, ret = 0; bool is_tracepoint = false; + bool is_return = false; if ((argv[0][0] != 'f' && argv[0][0] != 't') || argc < 2) return -ECANCELED; @@ -1273,6 +1273,9 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], trace_probe_log_set_index(0); if (event) { + gbuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); + if (!gbuf) + return -ENOMEM; ret = traceprobe_parse_event_name(&event, &group, gbuf, event - argv[0]); if (ret) @@ -1280,15 +1283,18 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], } if (!event) { + ebuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); + if (!ebuf) + return -ENOMEM; /* Make a new event name */ if (is_tracepoint) - snprintf(buf, MAX_EVENT_NAME_LEN, "%s%s", + snprintf(ebuf, MAX_EVENT_NAME_LEN, "%s%s", isdigit(*symbol) ? "_" : "", symbol); else - snprintf(buf, MAX_EVENT_NAME_LEN, "%s__%s", symbol, + snprintf(ebuf, MAX_EVENT_NAME_LEN, "%s__%s", symbol, is_return ? "exit" : "entry"); - sanitize_event_name(buf); - event = buf; + sanitize_event_name(ebuf); + event = ebuf; } if (is_return) @@ -1304,13 +1310,20 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], ctx->flags |= TPARG_FL_TPOINT; mod = NULL; tpoint = find_tracepoint(symbol, &mod); - if (tpoint) + if (tpoint) { + sbuf = kmalloc(KSYM_NAME_LEN, GFP_KERNEL); + if (!sbuf) + return -ENOMEM; ctx->funcname = kallsyms_lookup((unsigned long)tpoint->probestub, NULL, NULL, NULL, sbuf); + } } if (!ctx->funcname) ctx->funcname = symbol; + abuf = kmalloc(MAX_BTF_ARGS_LEN, GFP_KERNEL); + if (!abuf) + return -ENOMEM; argc -= 2; argv += 2; new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc, abuf, MAX_BTF_ARGS_LEN, ctx);
