TencentOS-kernel/include
Sabrina Dubroca 677d4bb667 net: don't return invalid table id error when we fall back to PF_UNSPEC
[ Upstream commit 41b4bd986f86331efc599b9a3f5fb86ad92e9af9 ]

In case we can't find a ->dumpit callback for the requested
(family,type) pair, we fall back to (PF_UNSPEC,type). In effect, we're
in the same situation as if userspace had requested a PF_UNSPEC
dump. For RTM_GETROUTE, that handler is rtnl_dump_all, which calls all
the registered RTM_GETROUTE handlers.

The requested table id may or may not exist for all of those
families. commit ae677bbb4441 ("net: Don't return invalid table id
error when dumping all families") fixed the problem when userspace
explicitly requests a PF_UNSPEC dump, but missed the fallback case.

For example, when we pass ipv6.disable=1 to a kernel with
CONFIG_IP_MROUTE=y and CONFIG_IP_MROUTE_MULTIPLE_TABLES=y,
the (PF_INET6, RTM_GETROUTE) handler isn't registered, so we end up in
rtnl_dump_all, and listing IPv6 routes will unexpectedly print:

  # ip -6 r
  Error: ipv4: MR table does not exist.
  Dump terminated

commit ae677bbb4441 introduced the dump_all_families variable, which
gets set when userspace requests a PF_UNSPEC dump. However, we can't
simply set the family to PF_UNSPEC in rtnetlink_rcv_msg in the
fallback case to get dump_all_families == true, because some messages
types (for example RTM_GETRULE and RTM_GETNEIGH) only register the
PF_UNSPEC handler and use the family to filter in the kernel what is
dumped to userspace. We would then export more entries, that userspace
would have to filter. iproute does that, but other programs may not.

Instead, this patch removes dump_all_families and updates the
RTM_GETROUTE handlers to check if the family that is being dumped is
their own. When it's not, which covers both the intentional PF_UNSPEC
dumps (as dump_all_families did) and the fallback case, ignore the
missing table id error.

Fixes: cb167893f41e ("net: Plumb support for filtering ipv4 and ipv6 multicast route dumps")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:28:22 +08:00
..
acpi x86: ACPI: fix CPU hotplug deadlock 2021-03-16 16:26:37 +08:00
asm-generic x86/Hyper-V: Report crash data in die() when panic_on_oops is set 2021-03-16 16:26:30 +08:00
clocksource Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
crypto Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2021-03-16 16:27:24 +08:00
dt-bindings Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
keys KEYS: Don't write out to userspace while holding key semaphore 2021-03-16 16:26:42 +08:00
kvm Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
linux bpf: Avoid setting bpf insns pages read-only when prog is jited 2021-03-16 16:28:17 +08:00
math-emu Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
media media: rc: add keymap for Videostrong KII Pro 2021-03-16 16:25:54 +08:00
misc Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
net net: don't return invalid table id error when we fall back to PF_UNSPEC 2021-03-16 16:28:22 +08:00
pcmcia Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ras Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
rdma Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
scsi Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
soc Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
sound ALSA: hda: Manage concurrent reg access more properly 2021-03-16 16:28:13 +08:00
target scsi: target: fix hang when multiple threads try to destroy the same iscsi session 2021-03-16 16:26:27 +08:00
trace rxrpc: Trace discarded ACKs 2021-03-16 16:28:21 +08:00
uapi dma-buf: Fix SET_NAME ioctl uapi 2021-03-16 16:27:16 +08:00
vdso Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
video Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
xen Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00