netdev - [PATCH bpf-next] bpf, x86: initialize the variable "first_off" in save

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date: Wed, 19 Jul 2023 19:03:30 +0800
From: menglong8.dong@...il.com
To: yhs@...com
Cc: davem@...emloft.net,
	dsahern@...nel.org,
	ast@...nel.org,
	daniel@...earbox.net,
	andrii@...nel.org,
	martin.lau@...ux.dev,
	song@...nel.org,
	john.fastabend@...il.com,
	kpsingh@...nel.org,
	sdf@...gle.com,
	haoluo@...gle.com,
	jolsa@...nel.org,
	tglx@...utronix.de,
	mingo@...hat.com,
	bp@...en8.de,
	dave.hansen@...ux.intel.com,
	x86@...nel.org,
	hpa@...or.com,
	imagedong@...cent.com,
	netdev@...r.kernel.org,
	bpf@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Hao Peng <flyingpeng@...cent.com>,
	Dan Carpenter <dan.carpenter@...aro.org>
Subject: [PATCH bpf-next] bpf, x86: initialize the variable "first_off" in save_args()

From: Menglong Dong <imagedong@...cent.com>

As Dan Carpenter reported, the variable "first_off" which is passed to
clean_stack_garbage() in save_args() can be uninitialized, which can
cause runtime warnings with KMEMsan. Therefore, init it with 0.

Fixes: 473e3150e30a ("bpf, x86: allow function arguments up to 12 for TRACING")
Cc: Hao Peng <flyingpeng@...cent.com>
Reported-by: Dan Carpenter <dan.carpenter@...aro.org>
Closes: https://lore.kernel.org/bpf/09784025-a812-493f-9829-5e26c8691e07@moroto.mountain/
Signed-off-by: Menglong Dong <imagedong@...cent.com>
---
 arch/x86/net/bpf_jit_comp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 5ab531be56ac..83c4b45dc65f 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1925,7 +1925,7 @@ static int get_nr_used_regs(const struct btf_func_model *m)
 static void save_args(const struct btf_func_model *m, u8 **prog,
 		      int stack_size, bool for_call_origin)
 {
-	int arg_regs, first_off, nr_regs = 0, nr_stack_slots = 0;
+	int arg_regs, first_off = 0, nr_regs = 0, nr_stack_slots = 0;
 	int i, j;
 
 	/* Store function arguments to stack.
-- 
2.40.1