The patch below does not apply to the 5.15-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-5.15.y git checkout FETCH_HEAD git cherry-pick -x ed4cccef64c1d0d5b91e69f7a8a6697c3a865486 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024040543-backdrop-sequester-2458@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From ed4cccef64c1d0d5b91e69f7a8a6697c3a865486 Mon Sep 17 00:00:00 2001 From: Antoine Tenart atenart@kernel.org Date: Tue, 26 Mar 2024 12:33:59 +0100 Subject: [PATCH] gro: fix ownership transfer

If packets are GROed with fraglist they might be segmented later on and continue their journey in the stack. In skb_segment_list those skbs can be reused as-is. This is an issue as their destructor was removed in skb_gro_receive_list but not the reference to their socket, and then they can't be orphaned. Fix this by also removing the reference to the socket.

For example this could be observed,

kernel BUG at include/linux/skbuff.h:3131! (skb_orphan) RIP: 0010:ip6_rcv_core+0x11bc/0x19a0 Call Trace: ipv6_list_rcv+0x250/0x3f0 __netif_receive_skb_list_core+0x49d/0x8f0 netif_receive_skb_list_internal+0x634/0xd40 napi_complete_done+0x1d2/0x7d0 gro_cell_poll+0x118/0x1f0

A similar construction is found in skb_gro_receive, apply the same change there.

Fixes: 5e10da5385d2 ("skbuff: allow 'slow_gro' for skb carring sock reference") Signed-off-by: Antoine Tenart atenart@kernel.org Reviewed-by: Willem de Bruijn willemb@google.com Signed-off-by: David S. Miller davem@davemloft.net

diff --git a/net/core/gro.c b/net/core/gro.c index ee30d4f0c038..83f35d99a682 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -192,8 +192,9 @@ int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb) }

merge: - /* sk owenrship - if any - completely transferred to the aggregated packet */ + /* sk ownership - if any - completely transferred to the aggregated packet */ skb->destructor = NULL; + skb->sk = NULL; delta_truesize = skb->truesize; if (offset > headlen) { unsigned int eat = offset - headlen; diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index e9719afe91cf..3bb69464930b 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -449,8 +449,9 @@ static int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb) NAPI_GRO_CB(p)->count++; p->data_len += skb->len;

- /* sk owenrship - if any - completely transferred to the aggregated packet */ + /* sk ownership - if any - completely transferred to the aggregated packet */ skb->destructor = NULL; + skb->sk = NULL; p->truesize += skb->truesize; p->len += skb->len;