--- /dev/null
+From b022f0c7e404887a7c5229788fc99eff9f9a80d5 Mon Sep 17 00:00:00 2001
+From: Francis Laniel <flaniel@linux.microsoft.com>
+Date: Fri, 20 Oct 2023 13:42:49 +0300
+Subject: tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols
+
+From: Francis Laniel <flaniel@linux.microsoft.com>
+
+commit b022f0c7e404887a7c5229788fc99eff9f9a80d5 upstream.
+
+When a kprobe is attached to a function that's name is not unique (is
+static and shares the name with other functions in the kernel), the
+kprobe is attached to the first function it finds. This is a bug as the
+function that it is attaching to is not necessarily the one that the
+user wants to attach to.
+
+Instead of blindly picking a function to attach to what is ambiguous,
+error with EADDRNOTAVAIL to let the user know that this function is not
+unique, and that the user must use another unique function with an
+address offset to get to the function they want to attach to.
+
+Link: https://lore.kernel.org/all/20231020104250.9537-2-flaniel@linux.microsoft.com/
+
+Cc: stable@vger.kernel.org
+Fixes: 413d37d1eb69 ("tracing: Add kprobe-based event tracer")
+Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
+Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com>
+Link: https://lore.kernel.org/lkml/20230819101105.b0c104ae4494a7d1f2eea742@kernel.org/
+Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
+Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/trace/trace_kprobe.c | 74 ++++++++++++++++++++++++++++++++++++++++++++
+ kernel/trace/trace_probe.h | 1
+ 2 files changed, 75 insertions(+)
+
+--- a/kernel/trace/trace_kprobe.c
++++ b/kernel/trace/trace_kprobe.c
+@@ -714,6 +714,36 @@ static inline void sanitize_event_name(c
+ *name = '_';
+ }
+
++struct count_symbols_struct {
++ const char *func_name;
++ unsigned int count;
++};
++
++static int count_symbols(void *data, const char *name, struct module *unused0,
++ unsigned long unused1)
++{
++ struct count_symbols_struct *args = data;
++
++ if (strcmp(args->func_name, name))
++ return 0;
++
++ args->count++;
++
++ return 0;
++}
++
++static unsigned int number_of_same_symbols(char *func_name)
++{
++ struct count_symbols_struct args = {
++ .func_name = func_name,
++ .count = 0,
++ };
++
++ kallsyms_on_each_symbol(count_symbols, &args);
++
++ return args.count;
++}
++
+ static int trace_kprobe_create(int argc, const char *argv[])
+ {
+ /*
+@@ -825,6 +855,31 @@ static int trace_kprobe_create(int argc,
+ }
+ }
+
++ if (symbol && !strchr(symbol, ':')) {
++ unsigned int count;
++
++ count = number_of_same_symbols(symbol);
++ if (count > 1) {
++ /*
++ * Users should use ADDR to remove the ambiguity of
++ * using KSYM only.
++ */
++ trace_probe_log_err(0, NON_UNIQ_SYMBOL);
++ ret = -EADDRNOTAVAIL;
++
++ goto error;
++ } else if (count == 0) {
++ /*
++ * We can return ENOENT earlier than when register the
++ * kprobe.
++ */
++ trace_probe_log_err(0, BAD_PROBE_ADDR);
++ ret = -ENOENT;
++
++ goto error;
++ }
++ }
++
+ trace_probe_log_set_index(0);
+ if (event) {
+ ret = traceprobe_parse_event_name(&event, &group, buf,
+@@ -1596,6 +1651,7 @@ static int unregister_kprobe_event(struc
+ }
+
+ #ifdef CONFIG_PERF_EVENTS
++
+ /* create a trace_kprobe, but don't add it to global lists */
+ struct trace_event_call *
+ create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
+@@ -1605,6 +1661,24 @@ create_local_trace_kprobe(char *func, vo
+ int ret;
+ char *event;
+
++ if (func) {
++ unsigned int count;
++
++ count = number_of_same_symbols(func);
++ if (count > 1)
++ /*
++ * Users should use addr to remove the ambiguity of
++ * using func only.
++ */
++ return ERR_PTR(-EADDRNOTAVAIL);
++ else if (count == 0)
++ /*
++ * We can return ENOENT earlier than when register the
++ * kprobe.
++ */
++ return ERR_PTR(-ENOENT);
++ }
++
+ /*
+ * local trace_kprobes are not added to dyn_event, so they are never
+ * searched in find_trace_kprobe(). Therefore, there is no concern of
+--- a/kernel/trace/trace_probe.h
++++ b/kernel/trace/trace_probe.h
+@@ -403,6 +403,7 @@ extern int traceprobe_define_arg_fields(
+ C(BAD_MAXACT, "Invalid maxactive number"), \
+ C(MAXACT_TOO_BIG, "Maxactive is too big"), \
+ C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \
++ C(NON_UNIQ_SYMBOL, "The symbol is not unique"), \
+ C(BAD_RETPROBE, "Retprobe address must be an function entry"), \
+ C(NO_GROUP_NAME, "Group name is not specified"), \
+ C(GROUP_TOO_LONG, "Group name is too long"), \