linux-stable.git/drivers/net/netdevsim, branch linux-5.16.y

ipv6: fix data-race in fib6_info_hw_flags_set / fib6_purge_rt

2022-02-23T11:05:55+00:00

commit d95d6320ba7a51d61c097ffc3bcafcf70283414e upstream.

Because fib6_info_hw_flags_set() is called without any synchronization,
all accesses to gi6->offload, fi->trap and fi->offload_failed
need some basic protection like READ_ONCE()/WRITE_ONCE().

BUG: KCSAN: data-race in fib6_info_hw_flags_set / fib6_purge_rt

read to 0xffff8881087d5886 of 1 bytes by task 13953 on cpu 0:
 fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1007 [inline]
 fib6_purge_rt+0x4f/0x580 net/ipv6/ip6_fib.c:1033
 fib6_del_route net/ipv6/ip6_fib.c:1983 [inline]
 fib6_del+0x696/0x890 net/ipv6/ip6_fib.c:2028
 __ip6_del_rt net/ipv6/route.c:3876 [inline]
 ip6_del_rt+0x83/0x140 net/ipv6/route.c:3891
 __ipv6_dev_ac_dec+0x2b5/0x370 net/ipv6/anycast.c:374
 ipv6_dev_ac_dec net/ipv6/anycast.c:387 [inline]
 __ipv6_sock_ac_close+0x141/0x200 net/ipv6/anycast.c:207
 ipv6_sock_ac_close+0x79/0x90 net/ipv6/anycast.c:220
 inet6_release+0x32/0x50 net/ipv6/af_inet6.c:476
 __sock_release net/socket.c:650 [inline]
 sock_close+0x6c/0x150 net/socket.c:1318
 __fput+0x295/0x520 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x160/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff8881087d5886 of 1 bytes by task 1912 on cpu 1:
 fib6_info_hw_flags_set+0x155/0x3b0 net/ipv6/route.c:6230
 nsim_fib6_rt_hw_flags_set drivers/net/netdevsim/fib.c:668 [inline]
 nsim_fib6_rt_add drivers/net/netdevsim/fib.c:691 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:756 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:853 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:886 [inline]
 nsim_fib_event_work+0x284f/0x2cf0 drivers/net/netdevsim/fib.c:1477
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x2c7/0x2e0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

value changed: 0x22 -> 0x2a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1912 Comm: kworker/1:3 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events nsim_fib_event_work

Fixes: 0c5fcf9e249e ("IPv6: Add "offload failed" indication to routes")
Fixes: bb3c4ab93e44 ("ipv6: Add "offload" and "trap" indications to routes")
Signed-off-by: Eric Dumazet 
Cc: Amit Cohen 
Cc: Ido Schimmel 
Reported-by: syzbot 
Link: https://lore.kernel.org/r/20220216173217.3792411-2-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

netdevsim: Zero-initialize memory for new map's value in function nsim_bpf_map_alloc

2021-12-16T01:49:13+00:00

Zero-initialize memory for new map's value in function nsim_bpf_map_alloc
since it may cause a potential kernel information leak issue, as follows:
1. nsim_bpf_map_alloc calls nsim_map_alloc_elem to allocate elements for
a new map.
2. nsim_map_alloc_elem uses kmalloc to allocate map's value, but doesn't
zero it.
3. A user application can use IOCTL BPF_MAP_LOOKUP_ELEM to get specific
element's information in the map.
4. The kernel function map_lookup_elem will call bpf_map_copy_value to get
the information allocated at step-2, then use copy_to_user to copy to the
user buffer.
This can only leak information for an array map.

Fixes: 395cacb5f1a0 ("netdevsim: bpf: support fake map offload")
Suggested-by: Jakub Kicinski 
Acked-by: Jakub Kicinski 
Signed-off-by: Haimin Zhang 
Link: https://lore.kernel.org/r/20211215111530.72103-1-tcs.kernel@gmail.com
Signed-off-by: Jakub Kicinski

netdevsim: don't overwrite read only ethtool parms

2021-12-11T05:23:05+00:00

Ethtool ring feature has _max_pending attributes read-only.
Set only read-write attributes in nsim_set_ringparam.

This patch is useful, if netdevsim device is set-up using NetworkManager,
because NetworkManager sends 0 as MAX values, as it is pointless to
retrieve them in extra call, because they should be read-only. Then,
the device is left in incosistent state (value > MAX).

Fixes: a7fc6db099b5 ("netdevsim: support ethtool ring and coalesce settings")
Signed-off-by: Filip Pokryvka 
Link: https://lore.kernel.org/r/20211210175032.411872-1-fpokryvk@redhat.com
Signed-off-by: Jakub Kicinski

netdevsim: fix uninit value in nsim_drv_configure_vfs()

2021-11-01T23:29:56+00:00

Build bot points out that I missed initializing ret
after refactoring.

Reported-by: kernel test robot 
Fixes: 1c401078bcf3 ("netdevsim: move details of vf config to dev")
Link: https://lore.kernel.org/r/20211101221845.3188490-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

netdevsim: rename 'driver' entry points

2021-11-01T13:29:41+00:00

Rename functions serving as driver entry points
from nsim_dev_... to nsim_drv_... this makes the
API boundary between bus and dev clearer.

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: move max vf config to dev

2021-11-01T13:29:41+00:00

max_vfs is a strange little beast because the file
hangs off of nsim's debugfs, but it configures a field
in the bus device. Move it to dev.c, let's look at it
as if the device driver was imposing VF limit based
on FW info (like pci_sriov_set_totalvfs()).

Again, when moving refactor the function not to hold
the vfs lock pointlessly while parsing the input.
Wrap the access from the read side in READ_ONCE()
to appease concurrency checkers. Do not check if
return value from snprintf() is negative...

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: move details of vf config to dev

2021-11-01T13:29:41+00:00

Since "eswitch" configuration was added bus.c contains
a lot of device details which really belong to dev.c.

Restructure the code while moving it.

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: move vfconfig to nsim_dev

2021-11-01T13:29:41+00:00

When netdevsim got split into the faux bus vfconfig ended
up in the bus device (think pci_dev) which is strange because
it contains very networky not to say netdevy information.
Move it to nsim_dev, which is the driver "priv" structure
for the device.

To make sure we don't race with probe/remove take
the device lock (much like PCI).

While at it remove the NULL-checking of vfconfigs.
It appears to be pointless.

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: take rtnl_lock when assigning num_vfs

2021-11-01T13:29:41+00:00

Legacy VF NDOs look at num_vfs and then based on that
index into vfconfig. If we don't rtnl_lock() num_vfs
may get set to 0 and vfconfig freed/replaced while
the NDO is running.

We don't need to protect replacing vfconfig since it's
only done when num_vfs is 0.

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: remove max_vfs dentry

2021-10-30T04:15:08+00:00

Commit d395381909a3 ("netdevsim: Add max_vfs to bus_dev")
added this file and saved the dentry for no apparent reason.

Link: https://lore.kernel.org/r/20211028211753.22612-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski