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authorPaolo Bonzini <pbonzini@redhat.com>2024-05-10 10:49:02 -0400
committerPaolo Bonzini <pbonzini@redhat.com>2024-05-10 13:20:18 -0400
commit4232da23d75d173195c6766729e51947b64f83cd (patch)
tree7eb1420b118d452c0b497bf6267ecdfb0a6d5931 /net/unix/garbage.c
parentbbe10a5cc0c775e52e91c8b3b6547b59b2054f44 (diff)
parent7b7e584f90bf670d5c6f2b1fff884bf3b972cad4 (diff)
downloadlwn-4232da23d75d173195c6766729e51947b64f83cd.tar.gz
lwn-4232da23d75d173195c6766729e51947b64f83cd.zip
Merge tag 'loongarch-kvm-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD
LoongArch KVM changes for v6.10 1. Add ParaVirt IPI support. 2. Add software breakpoint support. 3. Add mmio trace events support.
Diffstat (limited to 'net/unix/garbage.c')
-rw-r--r--net/unix/garbage.c18
1 files changed, 17 insertions, 1 deletions
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index fa39b6265238..0104be9d4704 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -274,11 +274,22 @@ static void __unix_gc(struct work_struct *work)
* receive queues. Other, non candidate sockets _can_ be
* added to queue, so we must make sure only to touch
* candidates.
+ *
+ * Embryos, though never candidates themselves, affect which
+ * candidates are reachable by the garbage collector. Before
+ * being added to a listener's queue, an embryo may already
+ * receive data carrying SCM_RIGHTS, potentially making the
+ * passed socket a candidate that is not yet reachable by the
+ * collector. It becomes reachable once the embryo is
+ * enqueued. Therefore, we must ensure that no SCM-laden
+ * embryo appears in a (candidate) listener's queue between
+ * consecutive scan_children() calls.
*/
list_for_each_entry_safe(u, next, &gc_inflight_list, link) {
+ struct sock *sk = &u->sk;
long total_refs;
- total_refs = file_count(u->sk.sk_socket->file);
+ total_refs = file_count(sk->sk_socket->file);
WARN_ON_ONCE(!u->inflight);
WARN_ON_ONCE(total_refs < u->inflight);
@@ -286,6 +297,11 @@ static void __unix_gc(struct work_struct *work)
list_move_tail(&u->link, &gc_candidates);
__set_bit(UNIX_GC_CANDIDATE, &u->gc_flags);
__set_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags);
+
+ if (sk->sk_state == TCP_LISTEN) {
+ unix_state_lock_nested(sk, U_LOCK_GC_LISTENER);
+ unix_state_unlock(sk);
+ }
}
}