https://github.com/torvalds/linux
Revision 10cc514f451a0f239aa34f91bc9dc954a9397840 authored by Subash Abhinov Kasiviswanathan on 10 September 2019, 20:02:57 UTC, committed by David S. Miller on 12 September 2019, 10:55:34 UTC
In event of failure during register_netdevice, free_netdev is invoked immediately. free_netdev assumes that all the netdevice refcounts have been dropped prior to it being called and as a result frees and clears out the refcount pointer. However, this is not necessarily true as some of the operations in the NETDEV_UNREGISTER notifier handlers queue RCU callbacks for invocation after a grace period. The IPv4 callback in_dev_rcu_put tries to access the refcount after free_netdev is called which leads to a null de-reference- 44837.761523: <6> Unable to handle kernel paging request at virtual address 0000004a88287000 44837.761651: <2> pc : in_dev_finish_destroy+0x4c/0xc8 44837.761654: <2> lr : in_dev_finish_destroy+0x2c/0xc8 44837.762393: <2> Call trace: 44837.762398: <2> in_dev_finish_destroy+0x4c/0xc8 44837.762404: <2> in_dev_rcu_put+0x24/0x30 44837.762412: <2> rcu_nocb_kthread+0x43c/0x468 44837.762418: <2> kthread+0x118/0x128 44837.762424: <2> ret_from_fork+0x10/0x1c Fix this by waiting for the completion of the call_rcu() in case of register_netdevice errors. Fixes: 93ee31f14f6f ("[NET]: Fix free_netdev on register_netdev failure.") Cc: Sean Tranchetti <stranche@codeaurora.org> Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net>
1 parent d23dbc4
Tip revision: 10cc514f451a0f239aa34f91bc9dc954a9397840 authored by Subash Abhinov Kasiviswanathan on 10 September 2019, 20:02:57 UTC
net: Fix null de-reference of device refcount
net: Fix null de-reference of device refcount
Tip revision: 10cc514
File | Mode | Size |
---|---|---|
ac97 | ||
aoa | ||
arm | ||
atmel | ||
core | ||
drivers | ||
firewire | ||
hda | ||
i2c | ||
isa | ||
mips | ||
oss | ||
parisc | ||
pci | ||
pcmcia | ||
ppc | ||
sh | ||
soc | ||
sparc | ||
spi | ||
synth | ||
usb | ||
x86 | ||
xen | ||
Kconfig | -rw-r--r-- | 2.8 KB |
Makefile | -rw-r--r-- | 554 bytes |
ac97_bus.c | -rw-r--r-- | 2.9 KB |
last.c | -rw-r--r-- | 628 bytes |
sound_core.c | -rw-r--r-- | 14.3 KB |
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