This is a note to let you know that I've just added the patch titled af_key: add __GFP_ZERO flag for compose_sadb_supported in function pfkey_register to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: af_key-add-__gfp_zero-flag-for-compose_sadb_supporte.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 156993f1b50e83e9f3f6b8b3036ef3ebe70b0a73 Author: Haimin Zhang <tcs_kernel@xxxxxxxxxxx> Date: Tue Mar 8 11:20:28 2022 +0800 af_key: add __GFP_ZERO flag for compose_sadb_supported in function pfkey_register [ Upstream commit 9a564bccb78a76740ea9d75a259942df8143d02c ] Add __GFP_ZERO flag for compose_sadb_supported in function pfkey_register to initialize the buffer of supp_skb to fix a kernel-info-leak issue. 1) Function pfkey_register calls compose_sadb_supported to request a sk_buff. 2) compose_sadb_supported calls alloc_sbk to allocate a sk_buff, but it doesn't zero it. 3) If auth_len is greater 0, then compose_sadb_supported treats the memory as a struct sadb_supported and begins to initialize. But it just initializes the field sadb_supported_len and field sadb_supported_exttype without field sadb_supported_reserved. Reported-by: TCS Robot <tcs_robot@xxxxxxxxxxx> Signed-off-by: Haimin Zhang <tcs_kernel@xxxxxxxxxxx> Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/key/af_key.c b/net/key/af_key.c index d1364b858fdf..bd9b5c573b5a 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -1703,7 +1703,7 @@ static int pfkey_register(struct sock *sk, struct sk_buff *skb, const struct sad xfrm_probe_algs(); - supp_skb = compose_sadb_supported(hdr, GFP_KERNEL); + supp_skb = compose_sadb_supported(hdr, GFP_KERNEL | __GFP_ZERO); if (!supp_skb) { if (hdr->sadb_msg_satype != SADB_SATYPE_UNSPEC) pfk->registered &= ~(1<<hdr->sadb_msg_satype);