Merge tag 'block-7.0-20260227' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

Pull block fixes from Jens Axboe:
 "Two sets of fixes, one for drbd, and one for the zoned loop driver"

* tag 'block-7.0-20260227' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
  zloop: check for spurious options passed to remove
  zloop: advertise a volatile write cache
  drbd: fix null-pointer dereference on local read error
  drbd: Replace deprecated strcpy with strscpy
  drbd: fix "LOGIC BUG" in drbd_al_begin_io_nonblock()

Author: torvalds

drivers/block/drbd/drbd_actlog.c

@@ -483,38 +483,20 @@ void drbd_al_begin_io(struct drbd_device *device, struct drbd_interval *i)
 
 int drbd_al_begin_io_nonblock(struct drbd_device *device, struct drbd_interval *i)
 {
-	struct lru_cache *al = device->act_log;
 	/* for bios crossing activity log extent boundaries,
 	 * we may need to activate two extents in one go */
 	unsigned first = i->sector >> (AL_EXTENT_SHIFT-9);
 	unsigned last = i->size == 0 ? first : (i->sector + (i->size >> 9) - 1) >> (AL_EXTENT_SHIFT-9);
-	unsigned nr_al_extents;
-	unsigned available_update_slots;
 	unsigned enr;
 
-	D_ASSERT(device, first <= last);
-
-	nr_al_extents = 1 + last - first; /* worst case: all touched extends are cold. */
-	available_update_slots = min(al->nr_elements - al->used,
-				al->max_pending_changes - al->pending_changes);
-
-	/* We want all necessary updates for a given request within the same transaction
-	 * We could first check how many updates are *actually* needed,
-	 * and use that instead of the worst-case nr_al_extents */
-	if (available_update_slots < nr_al_extents) {
-		/* Too many activity log extents are currently "hot".
-		 *
-		 * If we have accumulated pending changes already,
-		 * we made progress.
-		 *
-		 * If we cannot get even a single pending change through,
-		 * stop the fast path until we made some progress,
-		 * or requests to "cold" extents could be starved. */
-		if (!al->pending_changes)
-			__set_bit(__LC_STARVING, &device->act_log->flags);
-		return -ENOBUFS;
+	if (i->partially_in_al_next_enr) {
+		D_ASSERT(device, first < i->partially_in_al_next_enr);
+		D_ASSERT(device, last >= i->partially_in_al_next_enr);
+		first = i->partially_in_al_next_enr;
 	}
 
+	D_ASSERT(device, first <= last);
+
 	/* Is resync active in this area? */
 	for (enr = first; enr <= last; enr++) {
 		struct lc_element *tmp;
@@ -529,14 +511,21 @@ int drbd_al_begin_io_nonblock(struct drbd_device *device, struct drbd_interval *
 		}
 	}
 
-	/* Checkout the refcounts.
-	 * Given that we checked for available elements and update slots above,
-	 * this has to be successful. */
+	/* Try to checkout the refcounts. */
 	for (enr = first; enr <= last; enr++) {
 		struct lc_element *al_ext;
 		al_ext = lc_get_cumulative(device->act_log, enr);
-		if (!al_ext)
-			drbd_info(device, "LOGIC BUG for enr=%u\n", enr);
+
+		if (!al_ext) {
+			/* Did not work. We may have exhausted the possible
+			 * changes per transaction. Or raced with someone
+			 * "locking" it against changes.
+			 * Remember where to continue from.
+			 */
+			if (enr > first)
+				i->partially_in_al_next_enr = enr;
+			return -ENOBUFS;
+		}
 	}
 	return 0;
 }
@@ -556,7 +545,11 @@ void drbd_al_complete_io(struct drbd_device *device, struct drbd_interval *i)
 
 	for (enr = first; enr <= last; enr++) {
 		extent = lc_find(device->act_log, enr);
-		if (!extent) {
+		/* Yes, this masks a bug elsewhere.  However, during normal
+		 * operation this is harmless, so no need to crash the kernel
+		 * by the BUG_ON(refcount == 0) in lc_put().
+		 */
+		if (!extent || extent->refcnt == 0) {
 			drbd_err(device, "al_complete_io() called on inactive extent %u\n", enr);
 			continue;
 		}

drivers/block/drbd/drbd_interval.h

@@ -8,12 +8,15 @@
 struct drbd_interval {
 	struct rb_node rb;
 	sector_t sector;		/* start sector of the interval */
-	unsigned int size;		/* size in bytes */
 	sector_t end;			/* highest interval end in subtree */
+	unsigned int size;		/* size in bytes */
 	unsigned int local:1		/* local or remote request? */;
 	unsigned int waiting:1;		/* someone is waiting for completion */
 	unsigned int completed:1;	/* this has been completed already;
 					 * ignore for conflict detection */
+
+	/* to resume a partially successful drbd_al_begin_io_nonblock(); */
+	unsigned int partially_in_al_next_enr;
 };
 
 static inline void drbd_clear_interval(struct drbd_interval *i)

drivers/block/drbd/drbd_main.c

@@ -32,6 +32,7 @@
 #include <linux/memcontrol.h>
 #include <linux/mm_inline.h>
 #include <linux/slab.h>
+#include <linux/string.h>
 #include <linux/random.h>
 #include <linux/reboot.h>
 #include <linux/notifier.h>
@@ -732,9 +733,9 @@ int drbd_send_sync_param(struct drbd_peer_device *peer_device)
 	}
 
 	if (apv >= 88)
-		strcpy(p->verify_alg, nc->verify_alg);
+		strscpy(p->verify_alg, nc->verify_alg);
 	if (apv >= 89)
-		strcpy(p->csums_alg, nc->csums_alg);
+		strscpy(p->csums_alg, nc->csums_alg);
 	rcu_read_unlock();
 
 	return drbd_send_command(peer_device, sock, cmd, size, NULL, 0);
@@ -745,6 +746,7 @@ int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cm
 	struct drbd_socket *sock;
 	struct p_protocol *p;
 	struct net_conf *nc;
+	size_t integrity_alg_len;
 	int size, cf;
 
 	sock = &connection->data;
@@ -762,8 +764,10 @@ int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cm
 	}
 
 	size = sizeof(*p);
-	if (connection->agreed_pro_version >= 87)
-		size += strlen(nc->integrity_alg) + 1;
+	if (connection->agreed_pro_version >= 87) {
+		integrity_alg_len = strlen(nc->integrity_alg) + 1;
+		size += integrity_alg_len;
+	}
 
 	p->protocol      = cpu_to_be32(nc->wire_protocol);
 	p->after_sb_0p   = cpu_to_be32(nc->after_sb_0p);
@@ -778,7 +782,7 @@ int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cm
 	p->conn_flags    = cpu_to_be32(cf);
 
 	if (connection->agreed_pro_version >= 87)
-		strcpy(p->integrity_alg, nc->integrity_alg);
+		strscpy(p->integrity_alg, nc->integrity_alg, integrity_alg_len);
 	rcu_read_unlock();
 
 	return __conn_send_command(connection, sock, cmd, size, NULL, 0);

drivers/block/drbd/drbd_receiver.c

@@ -3801,14 +3801,14 @@ static int receive_SyncParam(struct drbd_connection *connection, struct packet_i
 			*new_net_conf = *old_net_conf;
 
 			if (verify_tfm) {
-				strcpy(new_net_conf->verify_alg, p->verify_alg);
+				strscpy(new_net_conf->verify_alg, p->verify_alg);
 				new_net_conf->verify_alg_len = strlen(p->verify_alg) + 1;
 				crypto_free_shash(peer_device->connection->verify_tfm);
 				peer_device->connection->verify_tfm = verify_tfm;
 				drbd_info(device, "using verify-alg: \"%s\"\n", p->verify_alg);
 			}
 			if (csums_tfm) {
-				strcpy(new_net_conf->csums_alg, p->csums_alg);
+				strscpy(new_net_conf->csums_alg, p->csums_alg);
 				new_net_conf->csums_alg_len = strlen(p->csums_alg) + 1;
 				crypto_free_shash(peer_device->connection->csums_tfm);
 				peer_device->connection->csums_tfm = csums_tfm;

drivers/block/drbd/drbd_req.c

@@ -621,7 +621,8 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		break;
 
 	case READ_COMPLETED_WITH_ERROR:
-		drbd_set_out_of_sync(peer_device, req->i.sector, req->i.size);
+		drbd_set_out_of_sync(first_peer_device(device),
+				req->i.sector, req->i.size);
 		drbd_report_io_error(device, req);
 		__drbd_chk_io_error(device, DRBD_READ_ERROR);
 		fallthrough;

drivers/block/zloop.c

@@ -542,6 +542,21 @@ static void zloop_rw(struct zloop_cmd *cmd)
 	zloop_put_cmd(cmd);
 }
 
+/*
+ * Sync the entire FS containing the zone files instead of walking all files.
+ */
+static int zloop_flush(struct zloop_device *zlo)
+{
+	struct super_block *sb = file_inode(zlo->data_dir)->i_sb;
+	int ret;
+
+	down_read(&sb->s_umount);
+	ret = sync_filesystem(sb);
+	up_read(&sb->s_umount);
+
+	return ret;
+}
+
 static void zloop_handle_cmd(struct zloop_cmd *cmd)
 {
 	struct request *rq = blk_mq_rq_from_pdu(cmd);
@@ -562,11 +577,7 @@ static void zloop_handle_cmd(struct zloop_cmd *cmd)
 		zloop_rw(cmd);
 		return;
 	case REQ_OP_FLUSH:
-		/*
-		 * Sync the entire FS containing the zone files instead of
-		 * walking all files
-		 */
-		cmd->ret = sync_filesystem(file_inode(zlo->data_dir)->i_sb);
+		cmd->ret = zloop_flush(zlo);
 		break;
 	case REQ_OP_ZONE_RESET:
 		cmd->ret = zloop_reset_zone(zlo, rq_zone_no(rq));
@@ -981,7 +992,8 @@ static int zloop_ctl_add(struct zloop_options *opts)
 	struct queue_limits lim = {
 		.max_hw_sectors		= SZ_1M >> SECTOR_SHIFT,
 		.chunk_sectors		= opts->zone_size,
-		.features		= BLK_FEAT_ZONED,
+		.features		= BLK_FEAT_ZONED | BLK_FEAT_WRITE_CACHE,
+
 	};
 	unsigned int nr_zones, i, j;
 	struct zloop_device *zlo;
@@ -1162,7 +1174,12 @@ static int zloop_ctl_remove(struct zloop_options *opts)
 	int ret;
 
 	if (!(opts->mask & ZLOOP_OPT_ID)) {
-		pr_err("No ID specified\n");
+		pr_err("No ID specified for remove\n");
+		return -EINVAL;
+	}
+
+	if (opts->mask & ~ZLOOP_OPT_ID) {
+		pr_err("Invalid option specified for remove\n");
 		return -EINVAL;
 	}