FAILED: patch "[PATCH] tracing/kprobes: Fix symbol counting logic by looking at" failed to apply to 6.1-stable tree

FAILED: patch "[PATCH] tracing/kprobes: Fix symbol counting logic by looking at" failed to apply to 6.1-stable tree

[gregkh]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 926fe783c8a64b33997fec405cf1af3e61aed441
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023102922-handwrite-unpopular-0e1d@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 926fe783c8a64b33997fec405cf1af3e61aed441 Mon Sep 17 00:00:00 2001
From: Andrii Nakryiko <andrii@kernel.org>
Date: Fri, 27 Oct 2023 16:31:26 -0700
Subject: [PATCH] tracing/kprobes: Fix symbol counting logic by looking at
 modules as well

Recent changes to count number of matching symbols when creating
a kprobe event failed to take into account kernel modules. As such, it
breaks kprobes on kernel module symbols, by assuming there is no match.

Fix this my calling module_kallsyms_on_each_symbol() in addition to
kallsyms_on_each_match_symbol() to perform a proper counting.

Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/

Cc: Francis Laniel <flaniel@linux.microsoft.com>
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 95c5b0668cb7..e834f149695b 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -714,14 +714,30 @@ static int count_symbols(void *data, unsigned long unused)
 	return 0;
 }
 
+struct sym_count_ctx {
+	unsigned int count;
+	const char *name;
+};
+
+static int count_mod_symbols(void *data, const char *name, unsigned long unused)
+{
+	struct sym_count_ctx *ctx = data;
+
+	if (strcmp(name, ctx->name) == 0)
+		ctx->count++;
+
+	return 0;
+}
+
 static unsigned int number_of_same_symbols(char *func_name)
 {
-	unsigned int count;
+	struct sym_count_ctx ctx = { .count = 0, .name = func_name };
+
+	kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
 
-	count = 0;
-	kallsyms_on_each_match_symbol(count_symbols, func_name, &count);
+	module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx);
 
-	return count;
+	return ctx.count;
 }
 
 static int __trace_kprobe_create(int argc, const char *argv[])

[PATCH 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Hao Wei Tee]

From: Andrii Nakryiko <andrii@kernel.org>

Recent changes to count number of matching symbols when creating
a kprobe event failed to take into account kernel modules. As such, it
breaks kprobes on kernel module symbols, by assuming there is no match.

Fix this my calling module_kallsyms_on_each_symbol() in addition to
kallsyms_on_each_match_symbol() to perform a proper counting.

Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/

Cc: Francis Laniel <flaniel@linux.microsoft.com>
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
(cherry picked from commit 926fe783c8a64b33997fec405cf1af3e61aed441)
---
 kernel/trace/trace_kprobe.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index a34a4fcdab7b..de11845df6d1 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -714,14 +714,30 @@ static int count_symbols(void *data, unsigned long unused)
 	return 0;
 }
 
+struct sym_count_ctx {
+	unsigned int count;
+	const char *name;
+};
+
+static int count_mod_symbols(void *data, const char *name, unsigned long unused)
+{
+	struct sym_count_ctx *ctx = data;
+
+	if (strcmp(name, ctx->name) == 0)
+		ctx->count++;
+
+	return 0;
+}
+
 static unsigned int number_of_same_symbols(char *func_name)
 {
-	unsigned int count;
+	struct sym_count_ctx ctx = { .count = 0, .name = func_name };
+
+	kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
 
-	count = 0;
-	kallsyms_on_each_match_symbol(count_symbols, func_name, &count);
+	module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx);
 
-	return count;
+	return ctx.count;
 }
 
 static int __trace_kprobe_create(int argc, const char *argv[])
-- 
2.43.0

Re: [PATCH 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Tee Hao Wei]

On Thu, 21 Dec 2023, at 01:00, Hao Wei Tee wrote:
> From: Andrii Nakryiko <andrii@kernel.org>
> 
> Recent changes to count number of matching symbols when creating
> a kprobe event failed to take into account kernel modules. As such, it
> breaks kprobes on kernel module symbols, by assuming there is no match.
> 
> Fix this my calling module_kallsyms_on_each_symbol() in addition to
> kallsyms_on_each_match_symbol() to perform a proper counting.
> 
> Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/
> 
> Cc: Francis Laniel <flaniel@linux.microsoft.com>
> Cc: stable@vger.kernel.org
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> Acked-by: Song Liu <song@kernel.org>
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> (cherry picked from commit 926fe783c8a64b33997fec405cf1af3e61aed441)

I noticed this patch was added and then dropped in the 6.1 stable queue. Is there any issue with it? I'll fix it ASAP.

Thanks.

-- 
Hao Wei

Re: [PATCH 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Greg KH]

On Sun, Dec 31, 2023 at 09:09:36PM +0800, Tee Hao Wei wrote:
> On Thu, 21 Dec 2023, at 01:00, Hao Wei Tee wrote:
> > From: Andrii Nakryiko <andrii@kernel.org>
> > 
> > Recent changes to count number of matching symbols when creating
> > a kprobe event failed to take into account kernel modules. As such, it
> > breaks kprobes on kernel module symbols, by assuming there is no match.
> > 
> > Fix this my calling module_kallsyms_on_each_symbol() in addition to
> > kallsyms_on_each_match_symbol() to perform a proper counting.
> > 
> > Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/
> > 
> > Cc: Francis Laniel <flaniel@linux.microsoft.com>
> > Cc: stable@vger.kernel.org
> > Cc: Masami Hiramatsu <mhiramat@kernel.org>
> > Cc: Steven Rostedt <rostedt@goodmis.org>
> > Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
> > Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> > Acked-by: Song Liu <song@kernel.org>
> > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > (cherry picked from commit 926fe783c8a64b33997fec405cf1af3e61aed441)
> 
> I noticed this patch was added and then dropped in the 6.1 stable queue. Is there any issue with it? I'll fix it ASAP.

It broke the build.

Re: [PATCH 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Francis Laniel]

Hi!


Le dimanche 31 décembre 2023, 14:09:36 CET Tee Hao Wei a écrit :
> On Thu, 21 Dec 2023, at 01:00, Hao Wei Tee wrote:
> > From: Andrii Nakryiko <andrii@kernel.org>
> > 
> > Recent changes to count number of matching symbols when creating
> > a kprobe event failed to take into account kernel modules. As such, it
> > breaks kprobes on kernel module symbols, by assuming there is no match.
> > 
> > Fix this my calling module_kallsyms_on_each_symbol() in addition to
> > kallsyms_on_each_match_symbol() to perform a proper counting.
> > 
> > Link:
> > https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/
> > 
> > Cc: Francis Laniel <flaniel@linux.microsoft.com>
> > Cc: stable@vger.kernel.org
> > Cc: Masami Hiramatsu <mhiramat@kernel.org>
> > Cc: Steven Rostedt <rostedt@goodmis.org>
> > Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func
> > matches several symbols") Signed-off-by: Andrii Nakryiko
> > <andrii@kernel.org>
> > Acked-by: Song Liu <song@kernel.org>
> > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > (cherry picked from commit 926fe783c8a64b33997fec405cf1af3e61aed441)
> 
> I noticed this patch was added and then dropped in the 6.1 stable queue. Is
> there any issue with it? I'll fix it ASAP.

Feel free to send me this updated patch privately, so I can also test it to 
ensure everything is correct before sending again to stable.
 
> Thanks.


Best regards.

[PATCH v2 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Hao Wei Tee]

From: Andrii Nakryiko <andrii@kernel.org>

commit 926fe783c8a64b33997fec405cf1af3e61aed441 upstream.

Recent changes to count number of matching symbols when creating
a kprobe event failed to take into account kernel modules. As such, it
breaks kprobes on kernel module symbols, by assuming there is no match.

Fix this my calling module_kallsyms_on_each_symbol() in addition to
kallsyms_on_each_match_symbol() to perform a proper counting.

Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/

Cc: Francis Laniel <flaniel@linux.microsoft.com>
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Hao Wei Tee <angelsl@in04.sg>
---
Fixed for 6.1. Please cherry-pick 73feb8d5fa3b755bb51077c0aabfb6aa556fd498 too.

Sorry for the bad patch originally. I had a mixup..

 kernel/trace/trace_kprobe.c | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index a34a4fcdab7b..e3993d19687d 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -714,14 +714,31 @@ static int count_symbols(void *data, unsigned long unused)
 	return 0;
 }
 
+struct sym_count_ctx {
+	unsigned int count;
+	const char *name;
+};
+
+static int count_mod_symbols(void *data, const char *name,
+			     struct module *module, unsigned long unused)
+{
+	struct sym_count_ctx *ctx = data;
+
+	if (strcmp(name, ctx->name) == 0)
+		ctx->count++;
+
+	return 0;
+}
+
 static unsigned int number_of_same_symbols(char *func_name)
 {
-	unsigned int count;
+	struct sym_count_ctx ctx = { .count = 0, .name = func_name };
+
+	kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
 
-	count = 0;
-	kallsyms_on_each_match_symbol(count_symbols, func_name, &count);
+	module_kallsyms_on_each_symbol(count_mod_symbols, &ctx);
 
-	return count;
+	return ctx.count;
 }
 
 static int __trace_kprobe_create(int argc, const char *argv[])
-- 
2.43.0

Re: [PATCH 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Tee Hao Wei]

On Tue, 2 Jan 2024, at 16:46, Francis Laniel wrote:
> Feel free to send me this updated patch privately, so I can also test it to 
> ensure everything is correct before sending again to stable.

Thanks for the offer! I think the patch should be good now.. 

-- 
Hao Wei

Re: [PATCH v2 6.1.y] tracing/kprobes: Fix symbol counting logic by looking at modules as well

[Greg KH]

On Thu, Jan 04, 2024 at 12:33:19AM +0800, Hao Wei Tee wrote:
> From: Andrii Nakryiko <andrii@kernel.org>
> 
> commit 926fe783c8a64b33997fec405cf1af3e61aed441 upstream.
> 
> Recent changes to count number of matching symbols when creating
> a kprobe event failed to take into account kernel modules. As such, it
> breaks kprobes on kernel module symbols, by assuming there is no match.
> 
> Fix this my calling module_kallsyms_on_each_symbol() in addition to
> kallsyms_on_each_match_symbol() to perform a proper counting.
> 
> Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/
> 
> Cc: Francis Laniel <flaniel@linux.microsoft.com>
> Cc: stable@vger.kernel.org
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> Acked-by: Song Liu <song@kernel.org>
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> Signed-off-by: Hao Wei Tee <angelsl@in04.sg>
> ---
> Fixed for 6.1. Please cherry-pick 73feb8d5fa3b755bb51077c0aabfb6aa556fd498 too.

Both now queued up now, thanks.

greg k-h