linux/drivers/net/netdevsim/netdevsim.h
Taehee Yoo f5cd21605e netdevsim: fix using uninitialized resources
When module is being initialized, __init() calls bus_register() and
driver_register().
These functions internally create various resources and sysfs files.
The sysfs files are used for basic operations(add/del device).
/sys/bus/netdevsim/new_device
/sys/bus/netdevsim/del_device

These sysfs files use netdevsim resources, they are mostly allocated
and initialized in ->probe() function, which is nsim_dev_probe().
But, sysfs files could be executed before ->probe() is finished.
So, accessing uninitialized data would occur.

Another problem is very similar.
/sys/bus/netdevsim/new_device internally creates sysfs files.
/sys/devices/netdevsim<id>/new_port
/sys/devices/netdevsim<id>/del_port

These sysfs files also use netdevsim resources, they are mostly allocated
and initialized in creating device routine, which is nsim_bus_dev_new().
But they also could be executed before nsim_bus_dev_new() is finished.
So, accessing uninitialized data would occur.

To fix these problems, this patch adds flags, which means whether the
operation is finished or not.
The flag variable 'nsim_bus_enable' means whether netdevsim bus was
initialized or not.
This is protected by nsim_bus_dev_list_lock.
The flag variable 'nsim_bus_dev->init' means whether nsim_bus_dev was
initialized or not.
This could be used in {new/del}_port_store() with no lock.

Test commands:
    #SHELL1
    modprobe netdevsim
    while :
    do
        echo "1 1" > /sys/bus/netdevsim/new_device
        echo "1 1" > /sys/bus/netdevsim/del_device
    done

    #SHELL2
    while :
    do
        echo 1 > /sys/devices/netdevsim1/new_port
        echo 1 > /sys/devices/netdevsim1/del_port
    done

Splat looks like:
[   47.508954][ T1008] general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 I
[   47.510793][ T1008] KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
[   47.511963][ T1008] CPU: 2 PID: 1008 Comm: bash Not tainted 5.5.0+ #322
[   47.512823][ T1008] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   47.514041][ T1008] RIP: 0010:__mutex_lock+0x10a/0x14b0
[   47.514699][ T1008] Code: 08 84 d2 0f 85 7f 12 00 00 44 8b 0d 10 23 65 02 45 85 c9 75 29 49 8d 7f 68 48 b8 00 00 00 0f
[   47.517163][ T1008] RSP: 0018:ffff888059b4fbb0 EFLAGS: 00010206
[   47.517802][ T1008] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   47.518941][ T1008] RDX: 0000000000000021 RSI: ffffffff85926440 RDI: 0000000000000108
[   47.519732][ T1008] RBP: ffff888059b4fd30 R08: ffffffffc073fad0 R09: 0000000000000000
[   47.520729][ T1008] R10: ffff888059b4fd50 R11: ffff88804bb38040 R12: 0000000000000000
[   47.521702][ T1008] R13: dffffc0000000000 R14: ffffffff871976c0 R15: 00000000000000a0
[   47.522760][ T1008] FS:  00007fd4be05a740(0000) GS:ffff88806c800000(0000) knlGS:0000000000000000
[   47.523877][ T1008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   47.524627][ T1008] CR2: 0000561c82b69cf0 CR3: 0000000065dd6004 CR4: 00000000000606e0
[   47.527662][ T1008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   47.528604][ T1008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   47.529531][ T1008] Call Trace:
[   47.529874][ T1008]  ? nsim_dev_port_add+0x50/0x150 [netdevsim]
[   47.530470][ T1008]  ? mutex_lock_io_nested+0x1380/0x1380
[   47.531018][ T1008]  ? _kstrtoull+0x76/0x160
[   47.531449][ T1008]  ? _parse_integer+0xf0/0xf0
[   47.531874][ T1008]  ? kernfs_fop_write+0x1cf/0x410
[   47.532330][ T1008]  ? sysfs_file_ops+0x160/0x160
[   47.532773][ T1008]  ? kstrtouint+0x86/0x110
[   47.533168][ T1008]  ? nsim_dev_port_add+0x50/0x150 [netdevsim]
[   47.533721][ T1008]  nsim_dev_port_add+0x50/0x150 [netdevsim]
[   47.534336][ T1008]  ? sysfs_file_ops+0x160/0x160
[   47.534858][ T1008]  new_port_store+0x99/0xb0 [netdevsim]
[   47.535439][ T1008]  ? del_port_store+0xb0/0xb0 [netdevsim]
[   47.536035][ T1008]  ? sysfs_file_ops+0x112/0x160
[   47.536544][ T1008]  ? sysfs_kf_write+0x3b/0x180
[   47.537029][ T1008]  kernfs_fop_write+0x276/0x410
[   47.537548][ T1008]  ? __sb_start_write+0x215/0x2e0
[   47.538110][ T1008]  vfs_write+0x197/0x4a0
[ ... ]

Fixes: f9d9db47d3 ("netdevsim: add bus attributes to add new and delete devices")
Fixes: 794b2c05ca ("netdevsim: extend device attrs to support port addition and deletion")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-02-03 15:32:20 -08:00

248 lines
6.0 KiB
C

/*
* Copyright (C) 2017 Netronome Systems, Inc.
*
* This software is licensed under the GNU General License Version 2,
* June 1991 as shown in the file COPYING in the top-level directory of this
* source tree.
*
* THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
* OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
* THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/u64_stats_sync.h>
#include <net/devlink.h>
#include <net/xdp.h>
#define DRV_NAME "netdevsim"
#define NSIM_XDP_MAX_MTU 4000
#define NSIM_EA(extack, msg) NL_SET_ERR_MSG_MOD((extack), msg)
#define NSIM_IPSEC_MAX_SA_COUNT 33
#define NSIM_IPSEC_VALID BIT(31)
struct nsim_sa {
struct xfrm_state *xs;
__be32 ipaddr[4];
u32 key[4];
u32 salt;
bool used;
bool crypt;
bool rx;
};
struct nsim_ipsec {
struct nsim_sa sa[NSIM_IPSEC_MAX_SA_COUNT];
struct dentry *pfile;
u32 count;
u32 tx;
u32 ok;
};
struct netdevsim {
struct net_device *netdev;
struct nsim_dev *nsim_dev;
struct nsim_dev_port *nsim_dev_port;
u64 tx_packets;
u64 tx_bytes;
struct u64_stats_sync syncp;
struct nsim_bus_dev *nsim_bus_dev;
struct bpf_prog *bpf_offloaded;
u32 bpf_offloaded_id;
struct xdp_attachment_info xdp;
struct xdp_attachment_info xdp_hw;
bool bpf_tc_accept;
bool bpf_tc_non_bound_accept;
bool bpf_xdpdrv_accept;
bool bpf_xdpoffload_accept;
bool bpf_map_accept;
struct nsim_ipsec ipsec;
};
struct netdevsim *
nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port);
void nsim_destroy(struct netdevsim *ns);
#ifdef CONFIG_BPF_SYSCALL
int nsim_bpf_dev_init(struct nsim_dev *nsim_dev);
void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev);
int nsim_bpf_init(struct netdevsim *ns);
void nsim_bpf_uninit(struct netdevsim *ns);
int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf);
int nsim_bpf_disable_tc(struct netdevsim *ns);
int nsim_bpf_setup_tc_block_cb(enum tc_setup_type type,
void *type_data, void *cb_priv);
#else
static inline int nsim_bpf_dev_init(struct nsim_dev *nsim_dev)
{
return 0;
}
static inline void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev)
{
}
static inline int nsim_bpf_init(struct netdevsim *ns)
{
return 0;
}
static inline void nsim_bpf_uninit(struct netdevsim *ns)
{
}
static inline int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf)
{
return bpf->command == XDP_QUERY_PROG ? 0 : -EOPNOTSUPP;
}
static inline int nsim_bpf_disable_tc(struct netdevsim *ns)
{
return 0;
}
static inline int
nsim_bpf_setup_tc_block_cb(enum tc_setup_type type, void *type_data,
void *cb_priv)
{
return -EOPNOTSUPP;
}
#endif
enum nsim_resource_id {
NSIM_RESOURCE_NONE, /* DEVLINK_RESOURCE_ID_PARENT_TOP */
NSIM_RESOURCE_IPV4,
NSIM_RESOURCE_IPV4_FIB,
NSIM_RESOURCE_IPV4_FIB_RULES,
NSIM_RESOURCE_IPV6,
NSIM_RESOURCE_IPV6_FIB,
NSIM_RESOURCE_IPV6_FIB_RULES,
};
struct nsim_dev_health {
struct devlink_health_reporter *empty_reporter;
struct devlink_health_reporter *dummy_reporter;
struct dentry *ddir;
char *recovered_break_msg;
u32 binary_len;
bool fail_recover;
};
int nsim_dev_health_init(struct nsim_dev *nsim_dev, struct devlink *devlink);
void nsim_dev_health_exit(struct nsim_dev *nsim_dev);
struct nsim_dev_port {
struct list_head list;
struct devlink_port devlink_port;
unsigned int port_index;
struct dentry *ddir;
struct netdevsim *ns;
};
struct nsim_dev {
struct nsim_bus_dev *nsim_bus_dev;
struct nsim_fib_data *fib_data;
struct nsim_trap_data *trap_data;
struct dentry *ddir;
struct dentry *ports_ddir;
struct bpf_offload_dev *bpf_dev;
bool bpf_bind_accept;
u32 bpf_bind_verifier_delay;
struct dentry *ddir_bpf_bound_progs;
u32 prog_id_gen;
struct list_head bpf_bound_progs;
struct list_head bpf_bound_maps;
struct netdev_phys_item_id switch_id;
struct list_head port_list;
struct mutex port_list_lock; /* protects port list */
bool fw_update_status;
u32 max_macs;
bool test1;
bool dont_allow_reload;
bool fail_reload;
struct devlink_region *dummy_region;
struct nsim_dev_health health;
};
static inline struct net *nsim_dev_net(struct nsim_dev *nsim_dev)
{
return devlink_net(priv_to_devlink(nsim_dev));
}
int nsim_dev_init(void);
void nsim_dev_exit(void);
int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev);
void nsim_dev_remove(struct nsim_bus_dev *nsim_bus_dev);
int nsim_dev_port_add(struct nsim_bus_dev *nsim_bus_dev,
unsigned int port_index);
int nsim_dev_port_del(struct nsim_bus_dev *nsim_bus_dev,
unsigned int port_index);
struct nsim_fib_data *nsim_fib_create(struct devlink *devlink,
struct netlink_ext_ack *extack);
void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *fib_data);
u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
enum nsim_resource_id res_id, bool max);
#if IS_ENABLED(CONFIG_XFRM_OFFLOAD)
void nsim_ipsec_init(struct netdevsim *ns);
void nsim_ipsec_teardown(struct netdevsim *ns);
bool nsim_ipsec_tx(struct netdevsim *ns, struct sk_buff *skb);
#else
static inline void nsim_ipsec_init(struct netdevsim *ns)
{
}
static inline void nsim_ipsec_teardown(struct netdevsim *ns)
{
}
static inline bool nsim_ipsec_tx(struct netdevsim *ns, struct sk_buff *skb)
{
return true;
}
#endif
struct nsim_vf_config {
int link_state;
u16 min_tx_rate;
u16 max_tx_rate;
u16 vlan;
__be16 vlan_proto;
u16 qos;
u8 vf_mac[ETH_ALEN];
bool spoofchk_enabled;
bool trusted;
bool rss_query_enabled;
};
struct nsim_bus_dev {
struct device dev;
struct list_head list;
unsigned int port_count;
struct net *initial_net; /* Purpose of this is to carry net pointer
* during the probe time only.
*/
unsigned int num_vfs;
struct nsim_vf_config *vfconfigs;
bool init;
};
int nsim_bus_init(void);
void nsim_bus_exit(void);