#syz test
---
 lib/crypto/x86/poly1305.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/crypto/x86/poly1305.h b/lib/crypto/x86/poly1305.h
index ee92e3740a78..3b9f1024a18d 100644
--- a/lib/crypto/x86/poly1305.h
+++ b/lib/crypto/x86/poly1305.h
@@ -8,6 +8,7 @@
 #include <linux/jump_label.h>
 #include <linux/kernel.h>
 #include <linux/sizes.h>
+#include <linux/string.h>
 
 struct poly1305_arch_internal {
 	union {
@@ -86,6 +87,7 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(poly1305_use_avx512);
 static void poly1305_block_init(struct poly1305_block_state *state,
 				const u8 raw_key[POLY1305_BLOCK_SIZE])
 {
+	memset(state, 0, sizeof(struct poly1305_block_state));
 	poly1305_init_x86_64(state, raw_key);
 }
 
-- 
2.25.1

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+01fcd39a0d90cdb0e3df@syzkaller.appspotmail.com
Tested-by: syzbot+01fcd39a0d90cdb0e3df@syzkaller.appspotmail.com

Tested on:

commit:         6548d364 Merge tag 'cgroup-for-6.18-rc2-fixes' of git:..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1266fde2580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=bbd3e7f3c2e28265
dashboard link: https://syzkaller.appspot.com/bug?extid=01fcd39a0d90cdb0e3df
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=13b58e7c580000

Note: testing is done by a robot and is best-effort only.

On Tue, Oct 21, 2025 at 11:08:54AM +0800, Pei Xiao wrote:
> #syz test
> ---
>  lib/crypto/x86/poly1305.h | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/lib/crypto/x86/poly1305.h b/lib/crypto/x86/poly1305.h
> index ee92e3740a78..3b9f1024a18d 100644
> --- a/lib/crypto/x86/poly1305.h
> +++ b/lib/crypto/x86/poly1305.h
> @@ -8,6 +8,7 @@
>  #include <linux/jump_label.h>
>  #include <linux/kernel.h>
>  #include <linux/sizes.h>
> +#include <linux/string.h>
>  
>  struct poly1305_arch_internal {
>  	union {
> @@ -86,6 +87,7 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(poly1305_use_avx512);
>  static void poly1305_block_init(struct poly1305_block_state *state,
>  				const u8 raw_key[POLY1305_BLOCK_SIZE])
>  {
> +	memset(state, 0, sizeof(struct poly1305_block_state));
>  	poly1305_init_x86_64(state, raw_key);
>  }

Please stop sending random patches to me.  If you want to test
random patches, send it to syzbot only and not anyone else.

When you hit an uninitialised access in crypto code, it's usually
the caller at fault.  So I suggest that you focus your energies
further up the stack.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt