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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /net/batman-adv/bitarray.c
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'net/batman-adv/bitarray.c')
-rw-r--r--net/batman-adv/bitarray.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/net/batman-adv/bitarray.c b/net/batman-adv/bitarray.c
new file mode 100644
index 000000000..f814756d9
--- /dev/null
+++ b/net/batman-adv/bitarray.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) B.A.T.M.A.N. contributors:
+ *
+ * Simon Wunderlich, Marek Lindner
+ */
+
+#include "bitarray.h"
+#include "main.h"
+
+#include <linux/bitmap.h>
+
+#include "log.h"
+
+/**
+ * batadv_bitmap_shift_left() - shift the sequence number bitmap left
+ * @seq_bits: the sequence number bitmap to shift
+ * @n: number of positions to shift left
+ *
+ * Shift @seq_bits by @n positions. No-op if @n is not within the bounds of
+ * the bitmap.
+ */
+static void batadv_bitmap_shift_left(unsigned long *seq_bits, s32 n)
+{
+ if (n <= 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE)
+ return;
+
+ bitmap_shift_left(seq_bits, seq_bits, n, BATADV_TQ_LOCAL_WINDOW_SIZE);
+}
+
+/**
+ * batadv_bit_get_packet() - receive and process one packet within the sequence
+ * number window
+ * @priv: the bat priv with all the mesh interface information
+ * @seq_bits: pointer to the sequence number bitmap of received packets
+ * @seq_num_diff: difference between the current/received sequence number and
+ * the last sequence number
+ * @set_mark: whether this packet should be marked in seq_bits
+ *
+ * Return: true if the window was moved (either new or very old),
+ * false if the window was not moved/shifted.
+ */
+bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits,
+ s32 seq_num_diff, int set_mark)
+{
+ struct batadv_priv *bat_priv = priv;
+
+ /* sequence number is slightly older. We already got a sequence number
+ * higher than this one, so we just mark it.
+ */
+ if (seq_num_diff <= 0 && seq_num_diff > -BATADV_TQ_LOCAL_WINDOW_SIZE) {
+ if (set_mark)
+ batadv_set_bit(seq_bits, -seq_num_diff);
+ return false;
+ }
+
+ /* sequence number is slightly newer, so we shift the window and
+ * set the mark if required
+ */
+ if (seq_num_diff > 0 && seq_num_diff < BATADV_TQ_LOCAL_WINDOW_SIZE) {
+ batadv_bitmap_shift_left(seq_bits, seq_num_diff);
+
+ if (set_mark)
+ batadv_set_bit(seq_bits, 0);
+ return true;
+ }
+
+ /* sequence number is much newer, probably missed a lot of packets */
+ if (seq_num_diff >= BATADV_TQ_LOCAL_WINDOW_SIZE &&
+ seq_num_diff < BATADV_EXPECTED_SEQNO_RANGE) {
+ batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+ "We missed a lot of packets (%i) !\n",
+ seq_num_diff - 1);
+ bitmap_zero(seq_bits, BATADV_TQ_LOCAL_WINDOW_SIZE);
+ if (set_mark)
+ batadv_set_bit(seq_bits, 0);
+ return true;
+ }
+
+ /* received a much older packet. The other host either restarted
+ * or the old packet got delayed somewhere in the network. The
+ * packet should be dropped without calling this function if the
+ * seqno window is protected.
+ *
+ * seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE
+ * or
+ * seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE
+ */
+ batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+ "Other host probably restarted!\n");
+
+ bitmap_zero(seq_bits, BATADV_TQ_LOCAL_WINDOW_SIZE);
+ if (set_mark)
+ batadv_set_bit(seq_bits, 0);
+
+ return true;
+}