8d9f13dd40
[ Upstream commit 46ef5b89ec0ecf290d74c4aee844f063933c4da4 ] KASAN report null-ptr-deref error when register_netdev() failed: KASAN: null-ptr-deref in range [0x00000000000003c0-0x00000000000003c7] CPU: 2 PID: 422 Comm: ip Not tainted 5.8.0-rc4+ #12 Call Trace: ip6gre_init_net+0x4ab/0x580 ? ip6gre_tunnel_uninit+0x3f0/0x3f0 ops_init+0xa8/0x3c0 setup_net+0x2de/0x7e0 ? rcu_read_lock_bh_held+0xb0/0xb0 ? ops_init+0x3c0/0x3c0 ? kasan_unpoison_shadow+0x33/0x40 ? __kasan_kmalloc.constprop.0+0xc2/0xd0 copy_net_ns+0x27d/0x530 create_new_namespaces+0x382/0xa30 unshare_nsproxy_namespaces+0xa1/0x1d0 ksys_unshare+0x39c/0x780 ? walk_process_tree+0x2a0/0x2a0 ? trace_hardirqs_on+0x4a/0x1b0 ? _raw_spin_unlock_irq+0x1f/0x30 ? syscall_trace_enter+0x1a7/0x330 ? do_syscall_64+0x1c/0xa0 __x64_sys_unshare+0x2d/0x40 do_syscall_64+0x56/0xa0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ip6gre_tunnel_uninit() has set 'ign->fb_tunnel_dev' to NULL, later access to ign->fb_tunnel_dev cause null-ptr-deref. Fix it by saving 'ign->fb_tunnel_dev' to local variable ndev. Fixes: dafabb6590cb ("ip6_gre: fix use-after-free in ip6gre_tunnel_lookup()") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.