linux-stable/net/mpls
Jakub Kicinski fda6c89fe3 net: mpls: fix stale pointer if allocation fails during device rename
lianhui reports that when MPLS fails to register the sysctl table
under new location (during device rename) the old pointers won't
get overwritten and may be freed again (double free).

Handle this gracefully. The best option would be unregistering
the MPLS from the device completely on failure, but unfortunately
mpls_ifdown() can fail. So failing fully is also unreliable.

Another option is to register the new table first then only
remove old one if the new one succeeds. That requires more
code, changes order of notifications and two tables may be
visible at the same time.

sysctl point is not used in the rest of the code - set to NULL
on failures and skip unregister if already NULL.

Reported-by: lianhui tang <bluetlh@gmail.com>
Fixes: 0fae3bf018 ("mpls: handle device renames for per-device sysctls")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-15 10:26:37 +00:00
..
af_mpls.c net: mpls: fix stale pointer if allocation fails during device rename 2023-02-15 10:26:37 +00:00
internal.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-12-02 11:44:56 -08:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile
mpls_gso.c net: avoid infinite loop in mpls_gso_segment when mpls_hlen == 0 2021-03-09 16:12:20 -08:00
mpls_iptunnel.c mpls: load mpls_gso after mpls_iptunnel 2020-10-20 21:16:45 -07:00