The branch main has been updated by bz:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=cb13e826ec45e11e964e1921d281e0a06ca5e152

commit cb13e826ec45e11e964e1921d281e0a06ca5e152
Author:     Bjoern A. Zeeb <[email protected]>
AuthorDate: 2026-02-03 22:13:24 +0000
Commit:     Bjoern A. Zeeb <[email protected]>
CommitDate: 2026-07-17 15:48:54 +0000

    LinuxKPI: skbuff: add reference counting to the skb
    
    Sponsored by:   The FreeBSD Foundation
    MFC after:      3 days
---
 sys/compat/linuxkpi/common/src/linux_skbuff.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/sys/compat/linuxkpi/common/src/linux_skbuff.c 
b/sys/compat/linuxkpi/common/src/linux_skbuff.c
index 5af9633691a6..d57c277c3267 100644
--- a/sys/compat/linuxkpi/common/src/linux_skbuff.c
+++ b/sys/compat/linuxkpi/common/src/linux_skbuff.c
@@ -140,6 +140,7 @@ linuxkpi_alloc_skb(size_t size, gfp_t gfp)
        skb->head = skb->data = (uint8_t *)p;
        skb_reset_tail_pointer(skb);
        skb->end = skb->head + size;
+       refcount_set(&skb->refcnt, 1);
 
        SKB_TRACE_FMT(skb, "data %p size %zu", (skb) ? skb->data : NULL, size);
        return (skb);
@@ -180,6 +181,7 @@ linuxkpi_build_skb(void *data, size_t fragsz)
        skb->head = skb->data = data;
        skb_reset_tail_pointer(skb);
        skb->end = skb->head + fragsz;
+       refcount_set(&skb->refcnt, 1);
 
        return (skb);
 }
@@ -288,6 +290,20 @@ lkpi___skb_linearize(struct sk_buff *skb)
        return (0);
 }
 
+static bool
+lkpi_skb_refcount_release(struct sk_buff *skb)
+{
+       if (skb == NULL)
+               return (false);
+
+       /* Do we need further tests to avoid freeing this one? */
+
+       if (!refcount_dec_and_test(&skb->refcnt))
+               return (false);
+
+       return (true);
+}
+
 void
 linuxkpi_kfree_skb(struct sk_buff *skb)
 {
@@ -298,6 +314,11 @@ linuxkpi_kfree_skb(struct sk_buff *skb)
        if (skb == NULL)
                return;
 
+       if (!lkpi_skb_refcount_release(skb)) {
+               SKB_TRACE_FMT(skb, "not freed due to refcnt");
+               return;
+       }
+
        /*
         * XXX TODO this will go away once we have skb backed by mbuf.
         * currently we allow the mbuf to stay around and use a private

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