Commit 356d568f authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'net-remove-rtnl-from-fib_seq_sum' 

Eric Dumazet says:

====================
net: remove RTNL from fib_seq_sum()

This series is inspired by a syzbot report showing
rtnl contention and one thread blocked in:

7 locks held by syz-executor/10835:
  #0: ffff888033390420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline]
  #0: ffff888033390420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679
  #1: ffff88806df6bc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325
  #2: ffff888026fcf3c8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326
  #3: ffffffff8f56f848 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166
  #4: ffff88805e0140e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
  #4: ffff88805e0140e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005
  #5: ffff88805c5fb250 (&devlink->lock_key#55){+.+.}-{3:3}, at: nsim_drv_probe+0xcb/0xb80 drivers/net/netdevsim/dev.c:1534
  #6: ffffffff8fcd1748 (rtnl_mutex){+.+.}-{3:3}, at: fib_seq_sum+0x31/0x290 net/core/fib_notifier.c:46
====================

Link: https://patch.msgid.link/20241009184405.3752829-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents d677aebd 2698acd6

include/net/fib_notifier.h

+1 −1
Original line number Diff line number Diff line
@@ -28,7 +28,7 @@ enum fib_event_type { 
struct fib_notifier_ops {

	int family;

	struct list_head list;

	unsigned int (*fib_seq_read)(struct net *net);

	unsigned int (*fib_seq_read)(const struct net *net);

	int (*fib_dump)(struct net *net, struct notifier_block *nb,

			struct netlink_ext_ack *extack);

	struct module *owner;

include/net/fib_rules.h

+1 −1
Original line number Diff line number Diff line
@@ -176,7 +176,7 @@ int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table); 
bool fib_rule_matchall(const struct fib_rule *rule);

int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,

		   struct netlink_ext_ack *extack);

unsigned int fib_rules_seq_read(struct net *net, int family);

unsigned int fib_rules_seq_read(const struct net *net, int family);



int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,

		   struct netlink_ext_ack *extack);

include/net/ip6_fib.h

+4 −4
Original line number Diff line number Diff line
@@ -394,7 +394,7 @@ struct fib6_table { 
	struct fib6_node	tb6_root;

	struct inet_peer_base	tb6_peers;

	unsigned int		flags;

	unsigned int		fib_seq;

	unsigned int		fib_seq; /* writes protected by rtnl_mutex */

	struct hlist_head       tb6_gc_hlist;	/* GC candidates */

#define RT6_TABLE_HAS_DFLT_ROUTER	BIT(0)

};
@@ -563,7 +563,7 @@ int call_fib6_notifiers(struct net *net, enum fib_event_type event_type, 
int __net_init fib6_notifier_init(struct net *net);

void __net_exit fib6_notifier_exit(struct net *net);



unsigned int fib6_tables_seq_read(struct net *net);

unsigned int fib6_tables_seq_read(const struct net *net);

int fib6_tables_dump(struct net *net, struct notifier_block *nb,

		     struct netlink_ext_ack *extack);
@@ -632,7 +632,7 @@ void fib6_rules_cleanup(void); 
bool fib6_rule_default(const struct fib_rule *rule);

int fib6_rules_dump(struct net *net, struct notifier_block *nb,

		    struct netlink_ext_ack *extack);

unsigned int fib6_rules_seq_read(struct net *net);

unsigned int fib6_rules_seq_read(const struct net *net);



static inline bool fib6_rules_early_flow_dissect(struct net *net,

						 struct sk_buff *skb,
@@ -676,7 +676,7 @@ static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb, 
{

	return 0;

}

static inline unsigned int fib6_rules_seq_read(struct net *net)

static inline unsigned int fib6_rules_seq_read(const struct net *net)

{

	return 0;

}

include/net/ip_fib.h

+2 −2
Original line number Diff line number Diff line
@@ -347,7 +347,7 @@ static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb, 
	return 0;

}



static inline unsigned int fib4_rules_seq_read(struct net *net)

static inline unsigned int fib4_rules_seq_read(const struct net *net)

{

	return 0;

}
@@ -411,7 +411,7 @@ static inline bool fib4_has_custom_rules(const struct net *net) 
bool fib4_rule_default(const struct fib_rule *rule);

int fib4_rules_dump(struct net *net, struct notifier_block *nb,

		    struct netlink_ext_ack *extack);

unsigned int fib4_rules_seq_read(struct net *net);

unsigned int fib4_rules_seq_read(const struct net *net);



static inline bool fib4_rules_early_flow_dissect(struct net *net,

						 struct sk_buff *skb,

include/net/netns/ipv4.h

+1 −1
Original line number Diff line number Diff line
@@ -262,7 +262,7 @@ struct netns_ipv4 { 
#endif



	struct fib_notifier_ops	*notifier_ops;

	unsigned int	fib_seq;	/* protected by rtnl_mutex */

	unsigned int	fib_seq;	/* writes protected by rtnl_mutex */



	struct fib_notifier_ops	*ipmr_notifier_ops;

	unsigned int	ipmr_seq;	/* protected by rtnl_mutex */