diff mbox series

[net,v3,2/4] gro: fix ownership transfer

Message ID 20240322114624.160306-3-atenart@kernel.org (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series gro: various fixes related to UDP tunnels | expand

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Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 951 this patch: 951
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 956 this patch: 956
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 962 this patch: 962
netdev/checkpatch warning WARNING: line length of 85 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest warning net-next-2024-03-22--18-00 (tests: 578)

Commit Message

Antoine Tenart March 22, 2024, 11:46 a.m. UTC 
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>
---
 net/core/gro.c         | 3 ++-
 net/ipv4/udp_offload.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

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;