linux-stable/include/linux/if_macvlan.h
Eric Dumazet dd4fa1dae9 macvlan: macvlan_count_rx() needs to be aware of preemption
macvlan_count_rx() can be called from process context, it is thus
necessary to disable preemption before calling u64_stats_update_begin()

syzbot was able to spot this on 32bit arch:

WARNING: CPU: 1 PID: 4632 at include/linux/seqlock.h:271 __seqprop_assert include/linux/seqlock.h:271 [inline]
WARNING: CPU: 1 PID: 4632 at include/linux/seqlock.h:271 __seqprop_assert.constprop.0+0xf0/0x11c include/linux/seqlock.h:269
Modules linked in:
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 4632 Comm: kworker/1:3 Not tainted 5.12.0-rc2-syzkaller #0
Hardware name: ARM-Versatile Express
Workqueue: events macvlan_process_broadcast
Backtrace:
[<82740468>] (dump_backtrace) from [<827406dc>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:252)
 r7:00000080 r6:60000093 r5:00000000 r4:8422a3c4
[<827406c4>] (show_stack) from [<82751b58>] (__dump_stack lib/dump_stack.c:79 [inline])
[<827406c4>] (show_stack) from [<82751b58>] (dump_stack+0xb8/0xe8 lib/dump_stack.c:120)
[<82751aa0>] (dump_stack) from [<82741270>] (panic+0x130/0x378 kernel/panic.c:231)
 r7:830209b4 r6:84069ea4 r5:00000000 r4:844350d0
[<82741140>] (panic) from [<80244924>] (__warn+0xb0/0x164 kernel/panic.c:605)
 r3:8404ec8c r2:00000000 r1:00000000 r0:830209b4
 r7:0000010f
[<80244874>] (__warn) from [<82741520>] (warn_slowpath_fmt+0x68/0xd4 kernel/panic.c:628)
 r7:81363f70 r6:0000010f r5:83018e50 r4:00000000
[<827414bc>] (warn_slowpath_fmt) from [<81363f70>] (__seqprop_assert include/linux/seqlock.h:271 [inline])
[<827414bc>] (warn_slowpath_fmt) from [<81363f70>] (__seqprop_assert.constprop.0+0xf0/0x11c include/linux/seqlock.h:269)
 r8:5a109000 r7:0000000f r6:a568dac0 r5:89802300 r4:00000001
[<81363e80>] (__seqprop_assert.constprop.0) from [<81364af0>] (u64_stats_update_begin include/linux/u64_stats_sync.h:128 [inline])
[<81363e80>] (__seqprop_assert.constprop.0) from [<81364af0>] (macvlan_count_rx include/linux/if_macvlan.h:47 [inline])
[<81363e80>] (__seqprop_assert.constprop.0) from [<81364af0>] (macvlan_broadcast+0x154/0x26c drivers/net/macvlan.c:291)
 r5:89802300 r4:8a927740
[<8136499c>] (macvlan_broadcast) from [<81365020>] (macvlan_process_broadcast+0x258/0x2d0 drivers/net/macvlan.c:317)
 r10:81364f78 r9:8a86d000 r8:8a9c7e7c r7:8413aa5c r6:00000000 r5:00000000
 r4:89802840
[<81364dc8>] (macvlan_process_broadcast) from [<802696a4>] (process_one_work+0x2d4/0x998 kernel/workqueue.c:2275)
 r10:00000008 r9:8404ec98 r8:84367a02 r7:ddfe6400 r6:ddfe2d40 r5:898dac80
 r4:8a86d43c
[<802693d0>] (process_one_work) from [<80269dcc>] (worker_thread+0x64/0x54c kernel/workqueue.c:2421)
 r10:00000008 r9:8a9c6000 r8:84006d00 r7:ddfe2d78 r6:898dac94 r5:ddfe2d40
 r4:898dac80
[<80269d68>] (worker_thread) from [<80271f40>] (kthread+0x184/0x1a4 kernel/kthread.c:292)
 r10:85247e64 r9:898dac80 r8:80269d68 r7:00000000 r6:8a9c6000 r5:89a2ee40
 r4:8a97bd00
[<80271dbc>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158)
Exception stack(0x8a9c7fb0 to 0x8a9c7ff8)

Fixes: 412ca1550c ("macvlan: Move broadcasts into a work queue")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-10 15:20:24 -08:00

109 lines
2.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_IF_MACVLAN_H
#define _LINUX_IF_MACVLAN_H
#include <linux/if_link.h>
#include <linux/if_vlan.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <net/netlink.h>
#include <linux/u64_stats_sync.h>
struct macvlan_port;
#define MACVLAN_MC_FILTER_BITS 8
#define MACVLAN_MC_FILTER_SZ (1 << MACVLAN_MC_FILTER_BITS)
struct macvlan_dev {
struct net_device *dev;
struct list_head list;
struct hlist_node hlist;
struct macvlan_port *port;
struct net_device *lowerdev;
void *accel_priv;
struct vlan_pcpu_stats __percpu *pcpu_stats;
DECLARE_BITMAP(mc_filter, MACVLAN_MC_FILTER_SZ);
netdev_features_t set_features;
enum macvlan_mode mode;
u16 flags;
unsigned int macaddr_count;
u32 bc_queue_len_req;
#ifdef CONFIG_NET_POLL_CONTROLLER
struct netpoll *netpoll;
#endif
};
static inline void macvlan_count_rx(const struct macvlan_dev *vlan,
unsigned int len, bool success,
bool multicast)
{
if (likely(success)) {
struct vlan_pcpu_stats *pcpu_stats;
pcpu_stats = get_cpu_ptr(vlan->pcpu_stats);
u64_stats_update_begin(&pcpu_stats->syncp);
pcpu_stats->rx_packets++;
pcpu_stats->rx_bytes += len;
if (multicast)
pcpu_stats->rx_multicast++;
u64_stats_update_end(&pcpu_stats->syncp);
put_cpu_ptr(vlan->pcpu_stats);
} else {
this_cpu_inc(vlan->pcpu_stats->rx_errors);
}
}
extern void macvlan_common_setup(struct net_device *dev);
extern int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack);
extern void macvlan_dellink(struct net_device *dev, struct list_head *head);
extern int macvlan_link_register(struct rtnl_link_ops *ops);
#if IS_ENABLED(CONFIG_MACVLAN)
static inline struct net_device *
macvlan_dev_real_dev(const struct net_device *dev)
{
struct macvlan_dev *macvlan = netdev_priv(dev);
return macvlan->lowerdev;
}
#else
static inline struct net_device *
macvlan_dev_real_dev(const struct net_device *dev)
{
BUG();
return NULL;
}
#endif
static inline void *macvlan_accel_priv(struct net_device *dev)
{
struct macvlan_dev *macvlan = netdev_priv(dev);
return macvlan->accel_priv;
}
static inline bool macvlan_supports_dest_filter(struct net_device *dev)
{
struct macvlan_dev *macvlan = netdev_priv(dev);
return macvlan->mode == MACVLAN_MODE_PRIVATE ||
macvlan->mode == MACVLAN_MODE_VEPA ||
macvlan->mode == MACVLAN_MODE_BRIDGE;
}
static inline int macvlan_release_l2fw_offload(struct net_device *dev)
{
struct macvlan_dev *macvlan = netdev_priv(dev);
macvlan->accel_priv = NULL;
return dev_uc_add(macvlan->lowerdev, dev->dev_addr);
}
#endif /* _LINUX_IF_MACVLAN_H */