mirror-linux/include
Eric Dumazet 4c6c11ea0f net: refine dev_put()/dev_hold() debugging
We are still chasing some syzbot reports where we think a rogue dev_put()
is called with no corresponding prior dev_hold().
Unfortunately it eats a reference on dev->dev_refcnt taken by innocent
dev_hold_track(), meaning that the refcount saturation splat comes
too late to be useful.

Make sure that 'not tracked' dev_put() and dev_hold() better use
CONFIG_NET_DEV_REFCNT_TRACKER=y debug infrastructure:

Prior patch in the series allowed ref_tracker_alloc() and ref_tracker_free()
to be called with a NULL @trackerp parameter, and to use a separate refcount
only to detect too many put() even in the following case:

dev_hold_track(dev, tracker_1, GFP_ATOMIC);
 dev_hold(dev);
 dev_put(dev);
 dev_put(dev); // Should complain loudly here.
dev_put_track(dev, tracker_1); // instead of here

Add clarification about netdev_tracker_alloc() role.

v2: I replaced the dev_put() in linkwatch_do_dev()
    with __dev_put() because callers called netdev_tracker_free().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-05 15:22:45 +00:00
..
acpi
asm-generic bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
clocksource
crypto lib/crypto: blake2s: move hmac construction into wireguard 2022-01-18 13:03:55 +01:00
drm
dt-bindings Char/Misc and other driver changes for 5.17-rc1 2022-01-14 16:02:28 +01:00
keys
kunit kunit: replace kernel.h with the necessary inclusions 2022-01-20 08:52:54 +02:00
kvm RISCV: 2022-01-16 16:15:14 +02:00
linux net: refine dev_put()/dev_hold() debugging 2022-02-05 15:22:45 +00:00
math-emu
media
memory
misc
net net: gro: minor optimization for dev_gro_receive() 2022-02-05 15:13:52 +00:00
pcmcia
ras mm/hwpoison: remove MF_MSG_BUDDY_2ND and MF_MSG_POISONED_HUGE 2022-01-15 16:30:31 +02:00
rdma
scsi Merge branch 'akpm' (patches from Andrew) 2022-01-22 11:28:23 +02:00
soc
sound
target
trace Tracing fixes for 5.17-rc1: 2022-01-28 19:30:35 +02:00
uapi uapi: ioam: Insertion frequency 2022-02-04 20:24:45 -08:00
vdso
video
xen