net: dcb: choose correct policy to parse DCB_ATTR_BCN

The dcbnl_bcn_setcfg uses erroneous policy to parse tb[DCB_ATTR_BCN],
which is introduced in commit 859ee3c43812 ("DCB: Add support for DCB
BCN"

net: dcb: choose correct policy to parse DCB_ATTR_BCN

The dcbnl_bcn_setcfg uses erroneous policy to parse tb[DCB_ATTR_BCN],
which is introduced in commit 859ee3c43812 ("DCB: Add support for DCB
BCN"). Please see the comment in below code

static int dcbnl_bcn_setcfg(...)
{
...
ret = nla_parse_nested_deprecated(..., dcbnl_pfc_up_nest, .. )
// !!! dcbnl_pfc_up_nest for attributes
// DCB_PFC_UP_ATTR_0 to DCB_PFC_UP_ATTR_ALL in enum dcbnl_pfc_up_attrs
...
for (i = DCB_BCN_ATTR_RP_0; i <= DCB_BCN_ATTR_RP_7; i++) {
// !!! DCB_BCN_ATTR_RP_0 to DCB_BCN_ATTR_RP_7 in enum dcbnl_bcn_attrs
...
value_byte = nla_get_u8(data[i]);
...
}
...
for (i = DCB_BCN_ATTR_BCNA_0; i <= DCB_BCN_ATTR_RI; i++) {
// !!! DCB_BCN_ATTR_BCNA_0 to DCB_BCN_ATTR_RI in enum dcbnl_bcn_attrs
...
value_int = nla_get_u32(data[i]);
...
}
...
}

That is, the nla_parse_nested_deprecated uses dcbnl_pfc_up_nest
attributes to parse nlattr defined in dcbnl_pfc_up_attrs. But the
following access code fetch each nlattr as dcbnl_bcn_attrs attributes.
By looking up the associated nla_policy for dcbnl_bcn_attrs. We can find
the beginning part of these two policies are "same".

static const struct nla_policy dcbnl_pfc_up_nest[...] = {
[DCB_PFC_UP_ATTR_0] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_1] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_2] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_3] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_4] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_5] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_6] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_7] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_ALL] = {.type = NLA_FLAG},
};

static const struct nla_policy dcbnl_bcn_nest[...] = {
[DCB_BCN_ATTR_RP_0] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_1] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_2] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_3] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_4] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_5] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_6] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_7] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_ALL] = {.type = NLA_FLAG},
// from here is somewhat different
[DCB_BCN_ATTR_BCNA_0] = {.type = NLA_U32},
...
[DCB_BCN_ATTR_ALL] = {.type = NLA_FLAG},
};

Therefore, the current code is buggy and this
nla_parse_nested_deprecated could overflow the dcbnl_pfc_up_nest and use
the adjacent nla_policy to parse attributes from DCB_BCN_ATTR_BCNA_0.

Hence use the correct policy dcbnl_bcn_nest to parse the nested
tb[DCB_ATTR_BCN] TLV.

Fixes: 859ee3c43812 ("DCB: Add support for DCB BCN")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230801013248.87240-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: dcb: add helper functions to retrieve PCP and DSCP rewrite maps

Add two new helper functions to retrieve a mapping of priority to PCP
and DSCP bitmasks, where each bitmap contains ones in posit

net: dcb: add helper functions to retrieve PCP and DSCP rewrite maps

Add two new helper functions to retrieve a mapping of priority to PCP
and DSCP bitmasks, where each bitmap contains ones in positions that
match a rewrite entry.

dcb_ieee_getrewr_prio_dscp_mask_map() reuses the dcb_ieee_app_prio_map,
as this struct is already used for a similar mapping in the app table.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: add new rewrite table

Add new rewrite table and all the required functions, offload hooks and
bookkeeping for maintaining it. The rewrite table reuses the app struct,
and the entire set of

net: dcb: add new rewrite table

Add new rewrite table and all the required functions, offload hooks and
bookkeeping for maintaining it. The rewrite table reuses the app struct,
and the entire set of app selectors. As such, some bookeeping code can
be shared between the rewrite- and the APP table.

New functions for getting, setting and deleting entries has been added.
Apart from operating on the rewrite list, these functions do not emit a
DCB_APP_EVENT when the list os modified. The new dcb_getrewr does a
lookup based on selector and priority and returns the protocol, so that
mappings from priority to protocol, for a given selector and ifindex is
obtained.

Also, a new nested attribute has been added, that encapsulates one or
more app structs. This attribute is used to distinguish the two tables.

The dcb_lock used for the APP table is reused for the rewrite table.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: add new common function for set/del of app/rewr entries

In preparation for DCB rewrite. Add a new function for setting and
deleting both app and rewrite entries. Moving this into a separat

net: dcb: add new common function for set/del of app/rewr entries

In preparation for DCB rewrite. Add a new function for setting and
deleting both app and rewrite entries. Moving this into a separate
function reduces duplicate code, as both type of entries requires the
same set of checks. The function will now iterate through a configurable
nested attribute (app or rewrite attr), validate each attribute and call
the appropriate set- or delete function.

Note that this function always checks for nla_len(attr_itr) <
sizeof(struct dcb_app), which was only done in dcbnl_ieee_set and not in
dcbnl_ieee_del prior to this patch. This means, that any userspace tool
that used to shove in data < sizeof(struct dcb_app) would now receive
-ERANGE.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: modify dcb_app_add to take list_head ptr as parameter

In preparation to DCB rewrite. Modify dcb_app_add to take new struct
list_head * as parameter, to make the used list configurable. Thi

net: dcb: modify dcb_app_add to take list_head ptr as parameter

In preparation to DCB rewrite. Modify dcb_app_add to take new struct
list_head * as parameter, to make the used list configurable. This is
done to allow reusing the function for adding rewrite entries to the
rewrite table, which is introduced in a later patch.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: move getapptrust to separate function

This patch fixes a frame size warning, reported by kernel test robot.

>> net/dcb/dcbnl.c:1230:1: warning: the frame size of 1244 bytes is
>> larger t

net: dcb: move getapptrust to separate function

This patch fixes a frame size warning, reported by kernel test robot.

>> net/dcb/dcbnl.c:1230:1: warning: the frame size of 1244 bytes is
>> larger than 1024 bytes [-Wframe-larger-than=]

The getapptrust part of dcbnl_ieee_fill is moved to a separate function,
and the selector array is now dynamically allocated, instead of stack
allocated.

Tested on microchip sparx5 driver.

Fixes: 6182d5875c33 ("net: dcb: add new apptrust attribute")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://lore.kernel.org/r/20221114092950.2490451-1-daniel.machon@microchip.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

show more ...

net: dcb: add new apptrust attribute

Add new apptrust extension attributes to the 8021Qaz APP managed object.

Two new attributes, DCB_ATTR_DCB_APP_TRUST_TABLE and
DCB_ATTR_DCB_APP_TRUST, has been a

net: dcb: add new apptrust attribute

Add new apptrust extension attributes to the 8021Qaz APP managed object.

Two new attributes, DCB_ATTR_DCB_APP_TRUST_TABLE and
DCB_ATTR_DCB_APP_TRUST, has been added. Trusted selectors are passed in
the nested attribute DCB_ATTR_DCB_APP_TRUST, in order of precedence.

The new attributes are meant to allow drivers, whose hw supports the
notion of trust, to be able to set whether a particular app selector is
trusted - and in which order.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

show more ...

net: dcb: add new pcp selector to app object

Add new PCP selector for the 8021Qaz APP managed object.

As the PCP selector is not part of the 8021Qaz standard, a new non-std
extension attribute DCB_

net: dcb: add new pcp selector to app object

Add new PCP selector for the 8021Qaz APP managed object.

As the PCP selector is not part of the 8021Qaz standard, a new non-std
extension attribute DCB_ATTR_DCB_APP has been introduced. Also two
helper functions to translate between selector and app attribute type
has been added. The new selector has been given a value of 255, to
minimize the risk of future overlap of std- and non-std attributes.

The new DCB_ATTR_DCB_APP is sent alongside the ieee std attribute in the
app table. This means that the dcb_app struct can now both contain std-
and non-std app attributes. Currently there is no overlap between the
selector values of the two attributes.

The purpose of adding the PCP selector, is to be able to offload
PCP-based queue classification to the 8021Q Priority Code Point table,
see 6.9.3 of IEEE Std 802.1Q-2018.

PCP and DEI is encoded in the protocol field as 8*dei+pcp, so that a
mapping of PCP 2 and DEI 1 to priority 3 is encoded as {255, 10, 3}.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

show more ...

net: dcb: disable softirqs in dcbnl_flush_dev()

Ido Schimmel points out that since commit 52cff74eef5d ("dcbnl : Disable
software interrupts before taking dcb_lock"), the DCB API can be called
by dr

net: dcb: disable softirqs in dcbnl_flush_dev()

Ido Schimmel points out that since commit 52cff74eef5d ("dcbnl : Disable
software interrupts before taking dcb_lock"), the DCB API can be called
by drivers from softirq context.

One such in-tree example is the chelsio cxgb4 driver:
dcb_rpl
-> cxgb4_dcb_handle_fw_update
-> dcb_ieee_setapp

If the firmware for this driver happened to send an event which resulted
in a call to dcb_ieee_setapp() at the exact same time as another
DCB-enabled interface was unregistering on the same CPU, the softirq
would deadlock, because the interrupted process was already holding the
dcb_lock in dcbnl_flush_dev().

Fix this unlikely event by using spin_lock_bh() in dcbnl_flush_dev() as
in the rest of the dcbnl code.

Fixes: 91b0383fef06 ("net: dcb: flush lingering app table entries for unregistered devices")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220302193939.1368823-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: dcb: flush lingering app table entries for unregistered devices

If I'm not mistaken (and I don't think I am), the way in which the
dcbnl_ops work is that drivers call dcb_ieee_setapp() and this

net: dcb: flush lingering app table entries for unregistered devices

If I'm not mistaken (and I don't think I am), the way in which the
dcbnl_ops work is that drivers call dcb_ieee_setapp() and this populates
the application table with dynamically allocated struct dcb_app_type
entries that are kept in the module-global dcb_app_list.

However, nobody keeps exact track of these entries, and although
dcb_ieee_delapp() is supposed to remove them, nobody does so when the
interface goes away (example: driver unbinds from device). So the
dcb_app_list will contain lingering entries with an ifindex that no
longer matches any device in dcb_app_lookup().

Reclaim the lost memory by listening for the NETDEV_UNREGISTER event and
flushing the app table entries of interfaces that are now gone.

In fact something like this used to be done as part of the initial
commit (blamed below), but it was done in dcbnl_exit() -> dcb_flushapp(),
essentially at module_exit time. That became dead code after commit
7a6b6f515f77 ("DCB: fix kconfig option") which essentially merged
"tristate config DCB" and "bool config DCBNL" into a single "bool config
DCB", so net/dcb/dcbnl.c could not be built as a module anymore.

Commit 36b9ad8084bd ("net/dcb: make dcbnl.c explicitly non-modular")
recognized this and deleted dcbnl_exit() and dcb_flushapp() altogether,
leaving us with the version we have today.

Since flushing application table entries can and should be done as soon
as the netdevice disappears, fundamentally the commit that is to blame
is the one that introduced the design of this API.

Fixes: 9ab933ab2cc8 ("dcbnl: add appliction tlv handlers")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: disable softirqs in dcbnl_flush_dev()

[ Upstream commit 10b6bb62ae1a49ee818fc479cf57b8900176773e ]

Ido Schimmel points out that since commit 52cff74eef5d ("dcbnl : Disable
software interr

net: dcb: disable softirqs in dcbnl_flush_dev()

[ Upstream commit 10b6bb62ae1a49ee818fc479cf57b8900176773e ]

Ido Schimmel points out that since commit 52cff74eef5d ("dcbnl : Disable
software interrupts before taking dcb_lock"), the DCB API can be called
by drivers from softirq context.

One such in-tree example is the chelsio cxgb4 driver:
dcb_rpl
-> cxgb4_dcb_handle_fw_update
-> dcb_ieee_setapp

If the firmware for this driver happened to send an event which resulted
in a call to dcb_ieee_setapp() at the exact same time as another
DCB-enabled interface was unregistering on the same CPU, the softirq
would deadlock, because the interrupted process was already holding the
dcb_lock in dcbnl_flush_dev().

Fix this unlikely event by using spin_lock_bh() in dcbnl_flush_dev() as
in the rest of the dcbnl code.

Fixes: 91b0383fef06 ("net: dcb: flush lingering app table entries for unregistered devices")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220302193939.1368823-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

net: dcb: flush lingering app table entries for unregistered devices

commit 91b0383fef06f20b847fa9e4f0e3054ead0b1a1b upstream.

If I'm not mistaken (and I don't think I am), the way in which the
dcb

net: dcb: flush lingering app table entries for unregistered devices

commit 91b0383fef06f20b847fa9e4f0e3054ead0b1a1b upstream.

If I'm not mistaken (and I don't think I am), the way in which the
dcbnl_ops work is that drivers call dcb_ieee_setapp() and this populates
the application table with dynamically allocated struct dcb_app_type
entries that are kept in the module-global dcb_app_list.

However, nobody keeps exact track of these entries, and although
dcb_ieee_delapp() is supposed to remove them, nobody does so when the
interface goes away (example: driver unbinds from device). So the
dcb_app_list will contain lingering entries with an ifindex that no
longer matches any device in dcb_app_lookup().

Reclaim the lost memory by listening for the NETDEV_UNREGISTER event and
flushing the app table entries of interfaces that are now gone.

In fact something like this used to be done as part of the initial
commit (blamed below), but it was done in dcbnl_exit() -> dcb_flushapp(),
essentially at module_exit time. That became dead code after commit
7a6b6f515f77 ("DCB: fix kconfig option") which essentially merged
"tristate config DCB" and "bool config DCBNL" into a single "bool config
DCB", so net/dcb/dcbnl.c could not be built as a module anymore.

Commit 36b9ad8084bd ("net/dcb: make dcbnl.c explicitly non-modular")
recognized this and deleted dcbnl_exit() and dcb_flushapp() altogether,
leaving us with the version we have today.

Since flushing application table entries can and should be done as soon
as the netdevice disappears, fundamentally the commit that is to blame
is the one that introduced the design of this API.

Fixes: 9ab933ab2cc8 ("dcbnl: add appliction tlv handlers")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net: dcb: Return the correct errno code

When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Mille

net: dcb: Return the correct errno code

When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: Remove unnecessary INIT_LIST_HEAD()

The list_head dcb_app_list is initialized statically.
It is unnecessary to initialize by INIT_LIST_HEAD().

Reported-by: Hulk Robot <hulkci@huawei.com>

net: dcb: Remove unnecessary INIT_LIST_HEAD()

The list_head dcb_app_list is initialized statically.
It is unnecessary to initialize by INIT_LIST_HEAD().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: dcb: Accept RTM_GETDCB messages carrying set-like DCB commands

In commit 826f328e2b7e ("net: dcb: Validate netlink message in DCB
handler"), Linux started rejecting RTM_GETDCB netlink messages

net: dcb: Accept RTM_GETDCB messages carrying set-like DCB commands

In commit 826f328e2b7e ("net: dcb: Validate netlink message in DCB
handler"), Linux started rejecting RTM_GETDCB netlink messages if they
contained a set-like DCB_CMD_ command.

The reason was that privileges were only verified for RTM_SETDCB messages,
but the value that determined the action to be taken is the command, not
the message type. And validation of message type against the DCB command
was the obvious missing piece.

Unfortunately it turns out that mlnx_qos, a somewhat widely deployed tool
for configuration of DCB, accesses the DCB set-like APIs through
RTM_GETDCB.

Therefore do not bounce the discrepancy between message type and command.
Instead, in addition to validating privileges based on the actual message
type, validate them also based on the expected message type. This closes
the loophole of allowing DCB configuration on non-admin accounts, while
maintaining backward compatibility.

Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver")
Fixes: 826f328e2b7e ("net: dcb: Validate netlink message in DCB handler")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/a3edcfda0825f2aa2591801c5232f2bbf2d8a554.1610384801.git.me@pmachata.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: dcb: Validate netlink message in DCB handler

DCB uses the same handler function for both RTM_GETDCB and RTM_SETDCB
messages. dcb_doit() bounces RTM_SETDCB mesasges if the user does not have
the

net: dcb: Validate netlink message in DCB handler

DCB uses the same handler function for both RTM_GETDCB and RTM_SETDCB
messages. dcb_doit() bounces RTM_SETDCB mesasges if the user does not have
the CAP_NET_ADMIN capability.

However, the operation to be performed is not decided from the DCB message
type, but from the DCB command. Thus DCB_CMD_*_GET commands are used for
reading DCB objects, the corresponding SET and DEL commands are used for
manipulation.

The assumption is that set-like commands will be sent via an RTM_SETDCB
message, and get-like ones via RTM_GETDCB. However, this assumption is not
enforced.

It is therefore possible to manipulate DCB objects without CAP_NET_ADMIN
capability by sending the corresponding command in an RTM_GETDCB message.
That is a bug. Fix it by validating the type of the request message against
the type used for the response.

Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver")
Signed-off-by: Petr Machata <me@pmachata.org>
Link: https://lore.kernel.org/r/a2a9b88418f3a58ef211b718f2970128ef9e3793.1608673640.git.me@pmachata.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: dcb: Fix kerneldoc warnings

net//dcb/dcbnl.c:1836: warning: Function parameter or member 'app' not described in 'dcb_getapp'
net//dcb/dcbnl.c:1836: warning: Function parameter or member 'dev' n

net: dcb: Fix kerneldoc warnings

net//dcb/dcbnl.c:1836: warning: Function parameter or member 'app' not described in 'dcb_getapp'
net//dcb/dcbnl.c:1836: warning: Function parameter or member 'dev' not described in 'dcb_getapp'
net//dcb/dcbnl.c:1858: warning: Function parameter or member 'dev' not described in 'dcb_setapp'
net//dcb/dcbnl.c:1858: warning: Function parameter or member 'new' not described in 'dcb_setapp'
net//dcb/dcbnl.c:1899: warning: Function parameter or member 'app' not described in 'dcb_ieee_getapp_mask'
net//dcb/dcbnl.c:1899: warning: Function parameter or member 'dev' not described in 'dcb_ieee_getapp_mask'
net//dcb/dcbnl.c:1922: warning: Function parameter or member 'dev' not described in 'dcb_ieee_setapp'
net//dcb/dcbnl.c:1922: warning: Function parameter or member 'new' not described in 'dcb_ieee_setapp'
net//dcb/dcbnl.c:1953: warning: Function parameter or member 'del' not described in 'dcb_ieee_delapp'
net//dcb/dcbnl.c:1953: warning: Function parameter or member 'dev' not described in 'dcb_ieee_delapp'
net//dcb/dcbnl.c:1986: warning: Function parameter or member 'dev' not described in 'dcb_ieee_getapp_prio_dscp_mask_map'
net//dcb/dcbnl.c:1986: warning: Function parameter or member 'p_map' not described in 'dcb_ieee_getapp_prio_dscp_mask_map'
net//dcb/dcbnl.c:2016: warning: Function parameter or member 'dev' not described in 'dcb_ieee_getapp_dscp_prio_mask_map'
net//dcb/dcbnl.c:2016: warning: Function parameter or member 'p_map' not described in 'dcb_ieee_getapp_dscp_prio_mask_map'
net//dcb/dcbnl.c:2045: warning: Function parameter or member 'dev' not described in 'dcb_ieee_getapp_default_prio_mask'

For some of these warnings, change to comments to plain comments,
since no attempt is being made to follow kerneldoc syntax.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20201028010913.930929-1-andrew@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: dcb: Accept RTM_GETDCB messages carrying set-like DCB commands

[ Upstream commit df85bc140a4d6cbaa78d8e9c35154e1a2f0622c7 ]

In commit 826f328e2b7e ("net: dcb: Validate netlink message in DCB
h

net: dcb: Accept RTM_GETDCB messages carrying set-like DCB commands

[ Upstream commit df85bc140a4d6cbaa78d8e9c35154e1a2f0622c7 ]

In commit 826f328e2b7e ("net: dcb: Validate netlink message in DCB
handler"), Linux started rejecting RTM_GETDCB netlink messages if they
contained a set-like DCB_CMD_ command.

The reason was that privileges were only verified for RTM_SETDCB messages,
but the value that determined the action to be taken is the command, not
the message type. And validation of message type against the DCB command
was the obvious missing piece.

Unfortunately it turns out that mlnx_qos, a somewhat widely deployed tool
for configuration of DCB, accesses the DCB set-like APIs through
RTM_GETDCB.

Therefore do not bounce the discrepancy between message type and command.
Instead, in addition to validating privileges based on the actual message
type, validate them also based on the expected message type. This closes
the loophole of allowing DCB configuration on non-admin accounts, while
maintaining backward compatibility.

Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver")
Fixes: 826f328e2b7e ("net: dcb: Validate netlink message in DCB handler")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/a3edcfda0825f2aa2591801c5232f2bbf2d8a554.1610384801.git.me@pmachata.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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net: dcb: Validate netlink message in DCB handler

[ Upstream commit 826f328e2b7e8854dd42ea44e6519cd75018e7b1 ]

DCB uses the same handler function for both RTM_GETDCB and RTM_SETDCB
messages. dcb_do

net: dcb: Validate netlink message in DCB handler

[ Upstream commit 826f328e2b7e8854dd42ea44e6519cd75018e7b1 ]

DCB uses the same handler function for both RTM_GETDCB and RTM_SETDCB
messages. dcb_doit() bounces RTM_SETDCB mesasges if the user does not have
the CAP_NET_ADMIN capability.

However, the operation to be performed is not decided from the DCB message
type, but from the DCB command. Thus DCB_CMD_*_GET commands are used for
reading DCB objects, the corresponding SET and DEL commands are used for
manipulation.

The assumption is that set-like commands will be sent via an RTM_SETDCB
message, and get-like ones via RTM_GETDCB. However, this assumption is not
enforced.

It is therefore possible to manipulate DCB objects without CAP_NET_ADMIN
capability by sending the corresponding command in an RTM_GETDCB message.
That is a bug. Fix it by validating the type of the request message against
the type used for the response.

Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver")
Signed-off-by: Petr Machata <me@pmachata.org>
Link: https://lore.kernel.org/r/a2a9b88418f3a58ef211b718f2970128ef9e3793.1608673640.git.me@pmachata.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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net: DCB: Validate DCB_ATTR_DCB_BUFFER argument

The parameter passed via DCB_ATTR_DCB_BUFFER is a struct dcbnl_buffer. The
field prio2buffer is an array of IEEE_8021Q_MAX_PRIORITIES bytes, where
eac

net: DCB: Validate DCB_ATTR_DCB_BUFFER argument

The parameter passed via DCB_ATTR_DCB_BUFFER is a struct dcbnl_buffer. The
field prio2buffer is an array of IEEE_8021Q_MAX_PRIORITIES bytes, where
each value is a number of a buffer to direct that priority's traffic to.
That value is however never validated to lie within the bounds set by
DCBX_MAX_BUFFERS. The only driver that currently implements the callback is
mlx5 (maintainers CCd), and that does not do any validation either, in
particual allowing incorrect configuration if the prio2buffer value does
not fit into 4 bits.

Instead of offloading the need to validate the buffer index to drivers, do
it right there in core, and bounce the request if the value is too large.

CC: Parav Pandit <parav@nvidia.com>
CC: Saeed Mahameed <saeedm@nvidia.com>
Fixes: e549f6f9c098 ("net/dcb: Add dcbnl buffer attribute")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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dcb_doit: remove redundant skb check

skb cannot be NULL here since its already being accessed
before: sock_net(skb->sk). Remove the redundant null check.

Signed-off-by: Gaurav Singh <gaurav1086@gma

dcb_doit: remove redundant skb check

skb cannot be NULL here since its already being accessed
before: sock_net(skb->sk). Remove the redundant null check.

Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms and c

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 228 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.107155473@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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netlink: make validation more configurable for future strictness

We currently have two levels of strict validation:

1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes acce

netlink: make validation more configurable for future strictness

We currently have two levels of strict validation:

1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
- garbage at end of message accepted
2) strict (opt-in)
- NLA_UNSPEC attributes accepted
- attribute length >= expected accepted

Split out parsing strictness into four different options:
* TRAILING - check that there's no trailing data after parsing
attributes (in message or nested)
* MAXTYPE - reject attrs > max known type
* UNSPEC - reject attributes with NLA_UNSPEC policy entries
* STRICT_ATTRS - strictly validate attribute size

The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().

Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.

We end up with the following renames:
* nla_parse -> nla_parse_deprecated
* nla_parse_strict -> nla_parse_deprecated_strict
* nlmsg_parse -> nlmsg_parse_deprecated
* nlmsg_parse_strict -> nlmsg_parse_deprecated_strict
* nla_parse_nested -> nla_parse_nested_deprecated
* nla_validate_nested -> nla_validate_nested_deprecated

Using spatch, of course:
@@
expression TB, MAX, HEAD, LEN, POL, EXT;
@@
-nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
+nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)

@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)

@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)

@@
expression TB, MAX, NLA, POL, EXT;
@@
-nla_parse_nested(TB, MAX, NLA, POL, EXT)
+nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)

@@
expression START, MAX, POL, EXT;
@@
-nla_validate_nested(START, MAX, POL, EXT)
+nla_validate_nested_deprecated(START, MAX, POL, EXT)

@@
expression NLH, HDRLEN, MAX, POL, EXT;
@@
-nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
+nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)

For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.

Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.

Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.

In effect then, this adds fully strict validation for any new command.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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netlink: make nla_nest_start() add NLA_F_NESTED flag

Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not

netlink: make nla_nest_start() add NLA_F_NESTED flag

Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dcb: Add priority-to-DSCP map getters

On ingress, a network device such as a switch assigns to packets
priority based on various criteria. Common options include interpreting
PCP and DSCP field

net: dcb: Add priority-to-DSCP map getters

On ingress, a network device such as a switch assigns to packets
priority based on various criteria. Common options include interpreting
PCP and DSCP fields according to user configuration. When a packet
egresses the switch, a reverse process may rewrite PCP and/or DSCP
values according to packet priority.

The following three functions support a) obtaining a DSCP-to-priority
map or vice versa, and b) finding default-priority entries in APP
database.

The DCB subsystem supports for APP entries a very generous M:N mapping
between priorities and protocol identifiers. Understandably,
several (say) DSCP values can map to the same priority. But this
asymmetry holds the other way around as well--one priority can map to
several DSCP values. For this reason, the following functions operate in
terms of bitmaps, with ones in positions that match some APP entry.

- dcb_ieee_getapp_dscp_prio_mask_map() to compute for a given netdevice
a map of DSCP-to-priority-mask, which gives for each DSCP value a
bitmap of priorities related to that DSCP value by APP, along the
lines of dcb_ieee_getapp_mask().

- dcb_ieee_getapp_prio_dscp_mask_map() similarly to compute for a given
netdevice a map from priorities to a bitmap of DSCPs.

- dcb_ieee_getapp_default_prio_mask() which finds all default-priority
rules for a given port in APP database, and returns a mask of
priorities allowed by these default-priority rules.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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