git: 9d2e5039ee18 - stable/15 - ktls: Propagate EPG_FLAG_ANON to mapped mbufs

The branch stable/15 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=9d2e5039ee18eb9545b26a8934e650c1f06139cb

commit 9d2e5039ee18eb9545b26a8934e650c1f06139cb
Author:     Mark Johnston <[email protected]>
AuthorDate: 2026-07-29 18:45:36 +0000
Commit:     Mark Johnston <[email protected]>
CommitDate: 2026-08-06 13:24:43 +0000

    ktls: Propagate EPG_FLAG_ANON to mapped mbufs
    
    Otherwise ktls_mbuf_crypto_state() will reject mbufs created by
    _mb_unmapped_to_ext(), which arises when transmitting packets through an
    interface that doesn't support unmapped mbufs, and the loopback
    interface in particular.
    
    PR:             296498
    Fixes:          3444414cb463 ("ktls: Don't attempt to modify non-anonymous mbufs on the receive path")
    Reviewed by:    gallatin, jhb
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D57557
    
    (cherry picked from commit 815976ee14121bafe8a8ab002459d32f8928f2de)
---
 sys/kern/kern_mbuf.c | 3 +++
 sys/kern/uipc_ktls.c | 3 ++-
 sys/sys/mbuf.h       | 1 +
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/sys/kern/kern_mbuf.c b/sys/kern/kern_mbuf.c
index 90af03e29dfb..c3f59a66b84e 100644
--- a/sys/kern/kern_mbuf.c
+++ b/sys/kern/kern_mbuf.c
@@ -1022,6 +1022,9 @@ _mb_unmapped_to_ext(struct mbuf *m, struct mbuf **mres)
 		m_extadd(m_new, (char *)sf_buf_kva(sf), PAGE_SIZE,
 		    mb_unmapped_free_mext, sf, mref, m->m_flags & M_RDONLY,
 		    EXT_SFBUF);
+		m_new->m_ext.ext_flags |=
+		    (m->m_epg_flags & EPG_FLAG_ANON) != 0 ?
+		    EXT_FLAG_SFBUF_ANON : 0;
 		m_new->m_data += segoff;
 		m_new->m_len = seglen;
 
diff --git a/sys/kern/uipc_ktls.c b/sys/kern/uipc_ktls.c
index 5f7d061bfb55..06d1bcabc267 100644
--- a/sys/kern/uipc_ktls.c
+++ b/sys/kern/uipc_ktls.c
@@ -2442,7 +2442,8 @@ ktls_mbuf_crypto_state(struct mbuf *mb, int offset, int len)
 		    (mb->m_epg_flags & EPG_FLAG_ANON) == 0)
 			return (KTLS_MBUF_CRYPTO_ST_SHAREDMBUF);
 		if ((mb->m_flags & M_EXT) != 0 &&
-		    mb->m_ext.ext_type == EXT_SFBUF)
+		    mb->m_ext.ext_type == EXT_SFBUF &&
+		    (mb->m_ext.ext_flags & EXT_FLAG_SFBUF_ANON) == 0)
 			return (KTLS_MBUF_CRYPTO_ST_SHAREDMBUF);
 
 		m_flags_ored |= mb->m_flags;
diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index 8a0a8e31d5b4..cba7702c6ebb 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -617,6 +617,7 @@ m_epg_pagelen(const struct mbuf *m, int pidx, int pgoff)
  */
 #define	EXT_FLAG_EMBREF		0x000001	/* embedded ext_count */
 #define	EXT_FLAG_EXTREF		0x000002	/* external ext_cnt, notyet */
+#define	EXT_FLAG_SFBUF_ANON	0x000004	/* sendfile buffer is mutable */
 
 #define	EXT_FLAG_NOFREE		0x000010	/* don't free mbuf to pool, notyet */