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2016-11-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller3-1/+72
All conflicts were simple overlapping changes except perhaps for the Thunder driver. That driver has a change_mtu method explicitly for sending a message to the hardware. If that fails it returns an error. Normally a driver doesn't need an ndo_change_mtu method becuase those are usually just range changes, which are now handled generically. But since this extra operation is needed in the Thunder driver, it has to stay. However, if the message send fails we have to restore the original MTU before the change because the entire call chain expects that if an error is thrown by ndo_change_mtu then the MTU did not change. Therefore code is added to nicvf_change_mtu to remember the original MTU, and to restore it upon nicvf_update_hw_max_frs() failue. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18cfg80211: limit scan results cache sizeJohannes Berg2-0/+70
It's possible to make scanning consume almost arbitrary amounts of memory, e.g. by sending beacon frames with random BSSIDs at high rates while somebody is scanning. Limit the number of BSS table entries we're willing to cache to 1000, limiting maximum memory usage to maybe 4-5MB, but lower in practice - that would be the case for having both full-sized beacon and probe response frames for each entry; this seems not possible in practice, so a limit of 1000 entries will likely be closer to 0.5 MB. Cc: stable@vger.kernel.org Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-11-15cfg80211: add bitrate for 20MHz MCS 9Pedersen, Thomas1-1/+2
Some drivers (ath10k) report MCS 9 @ 20MHz, which technically isn't defined. To get more meaningful value than 0 out of this however, just extrapolate a bitrate from ratio of MCS 7 and 9 in channels where it is allowed. Signed-off-by: Thomas Pedersen <twp@qca.qualcomm.com> [add a comment about it in the code] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2-20/+19
Mostly simple overlapping changes. For example, David Ahern's adjacency list revamp in 'net-next' conflicted with an adjacency list traversal bug fix in 'net'. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29Merge tag 'mac80211-next-for-davem-2016-10-28' of ↵David S. Miller9-211/+467
git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next Johannes Berg says: ==================== Among various cleanups and improvements, we have the following: * client FILS authentication support in mac80211 (Jouni) * AP/VLAN multicast improvements (Michael Braun) * config/advertising support for differing beacon intervals on multiple virtual interfaces (Purushottam Kushwaha, myself) * deprecate the old WDS mode for cfg80211-based drivers, the mode is hardly usable since it doesn't support any "modern" features like WPA encryption (2003), HT (2009) or VHT (2014), I'm not even sure WEP (introduced in 1997) could be done. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29netlink: Add nla_memdup() to wrap kmemdup() use on nlattrThomas Graf1-2/+1
Wrap several common instances of: kmemdup(nla_data(attr), nla_len(attr), GFP_KERNEL); Signed-off-by: Thomas Graf <tgraf@suug.ch> Acked-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27genetlink: mark families as __ro_after_initJohannes Berg1-2/+2
Now genl_register_family() is the only thing (other than the users themselves, perhaps, but I didn't find any doing that) writing to the family struct. In all families that I found, genl_register_family() is only called from __init functions (some indirectly, in which case I've add __init annotations to clarifly things), so all can actually be marked __ro_after_init. This protects the data structure from accidental corruption. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27genetlink: statically initialize familiesJohannes Berg1-16/+17
Instead of providing macros/inline functions to initialize the families, make all users initialize them statically and get rid of the macros. This reduces the kernel code size by about 1.6k on x86-64 (with allyesconfig). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27genetlink: no longer support using static family IDsJohannes Berg1-1/+0
Static family IDs have never really been used, the only use case was the workaround I introduced for those users that assumed their family ID was also their multicast group ID. Additionally, because static family IDs would never be reserved by the generic netlink code, using a relatively low ID would only work for built-in families that can be registered immediately after generic netlink is started, which is basically only the control family (apart from the workaround code, which I also had to add code for so it would reserve those IDs) Thus, anything other than GENL_ID_GENERATE is flawed and luckily not used except in the cases I mentioned. Move those workarounds into a few lines of code, and then get rid of GENL_ID_GENERATE entirely, making it more robust. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27genetlink: introduce and use genl_family_attrbuf()Johannes Berg1-26/+25
This helper function allows family implementations to access their family's attrbuf. This gets rid of the attrbuf usage in families, and also adds locking validation, since it's not valid to use the attrbuf with parallel_ops or outside of the dumpit callback. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27cfg80211: Add support to update connection parametersvamsi krishna3-0/+70
Add functionality to update the connection parameters when in connected state, so that driver/firmware uses the updated parameters for subsequent roaming. This is for drivers that support internal BSS selection and roaming. The new command does not change the current association state, i.e., it can be used to update IE contents for future (re)associations without causing an immediate disassociation or reassociation with the current BSS. This commit implements the required functionality for updating IEs for (Re)Association Request frame only. Other parameters can be added in future when required. Signed-off-by: vamsi krishna <vamsin@qti.qualcomm.com> Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: handle fragmented IEs in splittingJohannes Berg1-3/+22
The IEs "output" can sometimes combine IEs coming from userspace with IEs generated in the kernel - in particular mac80211 does this for association frames. Add support in this code for the 802.11 IE fragmentation. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: configure multicast to unicast for AP interfacesMichael Braun3-0/+66
Add the ability to configure if an AP (and associated VLANs) will do multicast-to-unicast conversion for ARP, IPv4 and IPv6 frames (possibly within 802.1Q). If enabled, such frames are to be sent to each station separately, with the DA replaced by their own MAC address rather than the group address. Note that this may break certain expectations of the receiver, such as the ability to drop unicast IP packets received within multicast L2 frames, or the ability to not send ICMP destination unreachable messages for packets received in L2 multicast (which is required, but the receiver can't tell the difference if this new option is enabled.) This also doesn't implement the 802.11 DMS (directed multicast service). Signed-off-by: Michael Braun <michael-dev@fami-braun.de> [fix disabling, add better documentation & commit message] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: Add KEK/nonces for FILS association framesJouni Malinen1-0/+12
The new nl80211 attributes can be used to provide KEK and nonces to allow the driver to encrypt and decrypt FILS (Re)Association Request/Response frames in station mode. Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: Add Fast Initial Link Setup (FILS) auth algsJouni Malinen1-2/+19
This defines authentication algorithms for FILS (IEEE 802.11ai). Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: Rename SAE_DATA to more generic AUTH_DATAJouni Malinen3-13/+13
This adds defines and nl80211 extensions to allow FILS Authentication to be implemented similarly to SAE. FILS does not need the special rules for the Authentication transaction number and Status code fields, but it does need to add non-IE fields. The previously used NL80211_ATTR_SAE_DATA can be reused for this to avoid having to duplicate that implementation. Rename that attribute to more generic NL80211_ATTR_AUTH_DATA (with backwards compatibility define for NL80211_SAE_DATA). Also document the special rules related to the Authentication transaction number and Status code fiels. Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27nl80211: use nla_parse_nested() instead of nla_parse()Johannes Berg1-48/+37
It's just an inline doing the same thing, but the code is nicer with it. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27nl80211: move unsplit command advertising to a separate functionJohannes Berg1-75/+92
When we split the wiphy dump because it got too large, I added a comment and asked that all new command advertising be done only for userspace clients capable of receiving split data, in order to not break older ones (which can't use the new commands anyway) This mostly worked, and we haven't added many new commands, but I occasionally get patches that modify the wrong place. Make this easier to detect and understand by splitting out the old commands to a separate function that makes it more clear it should never be modified again. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: validate beacon int as part of iface combinationsJohannes Berg1-31/+52
Remove the pointless checking against interface combinations in the initial basic beacon interval validation, that currently isn't taking into account radar detection or channels properly. Instead, just validate the basic range there, and then delay real checking to the interface combination validation that drivers must do. This means that drivers wanting to use the beacon_int_min_gcd will now have to pass the new_beacon_int when validating the AP/mesh start. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: disallow beacon_int_min_gcd with IBSSJohannes Berg1-0/+15
This can't really be supported right now, because the IBSS interface may change its beacon interval at any time due to joining another network; thus, there's already "support" for different beacon intervals here, implicitly. Until we figure out how we should handle this case (continue to allow it to arbitrarily join? Join only if compatible?) disallow advertising that different beacon intervals are supported if IBSS is allowed. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: mesh: track (and thus validate) beacon intervalJohannes Berg1-0/+2
This is needed for beacon interval validation; if we don't store it, then new interfaces added won't validate that the beacon interval is the same as existing ones. Fix this. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: fix beacon interval in interface combination iterationJohannes Berg1-4/+2
We shouldn't abort the iteration with an error when one of the potential combinations can't accomodate the beacon interval request, we should just skip that particular combination. Fix the code to do so. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27cfg80211: add generic helper to check interface is runningArend Van Spriel2-41/+20
Add a helper using wdev to check if interface is running. This deals with both non-netdev and netdev interfaces. In struct wireless_dev replace 'p2p_started' and 'nan_started' by 'is_running' as those are mutually exclusive anyway, and unify all the code to use wdev_running(). Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27wireless: deprecate WDS and disable by defaultJohannes Berg1-0/+10
The old WDS 4-addr frame support is very limited, e.g. * no encryption is possible on such links * it cannot support rate/HT/VHT negotiation * management APIs are very restricted These make the WDS legacy mode useless in practice. All of these are resolved by the 4-addr AP/client support, so there's also no reason to improve WDS in the future. Therefore, add a Kconfig option to disable legacy WDS. This gives people an "emergency valve" while they migrate to the better-supported 4-addr AP/client option; we plan to remove it (and the associated cfg80211/mac80211 code, which is the ultimate goal) in the future. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-26cfg80211: process events caused by suspend before suspendingJohannes Berg1-1/+4
When suspending without WoWLAN, cfg80211 will ask drivers to disconnect. Even when the driver does this synchronously, and immediately returns with a notification, cfg80211 schedules the handling thereof to a workqueue, and may then call back into the driver when the driver was already suspended/ing. Fix this by processing all events caused by cfg80211_leave_all() directly after that function returns. The driver still needs to do the right thing here and wait for the firmware response, but that is - at least - true for mwifiex where this occurred. Reported-by: Amitkumar Karwar <akarwar@marvell.com> Tested-by: Amitkumar Karwar <akarwar@marvell.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19cfg80211: allow vendor commands to be sent to nan interfaceAndrei Otcheretianski1-1/+2
Allow vendor commands that require WIPHY_VENDOR_CMD_NEED_RUNNING flag to be sent to NAN interface. Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19cfg80211: allow aborting in-progress connection atttemptsIlan Peer1-1/+1
On a disconnect request from userspace, cfg80211 currently calls called rdev_disconnect() only in case that 'current_bss' was set, i.e. connection had been established. Change this to allow the userspace call to succeed and call the driver's disconnect() method also while the connection attempt is in progress, to be able to abort attempts. Signed-off-by: Ilan Peer <ilan.peer@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> [change commit subject/message] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-18cfg80211: fix possible memory leak in cfg80211_iter_combinations()Wei Yongjun1-1/+3
'limits' is malloced in cfg80211_iter_combinations() and should be freed before leaving from the error handling cases, otherwise it will cause memory leak. Fixes: 0c317a02ca98 ("cfg80211: support virtual interfaces with different beacon intervals") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-17nl80211: ifdef WoWLAN related policiesJohannes Berg1-0/+2
To avoid unused variable warnings when CONFIG_PM isn't set, add the appropriate ifdef to the policies that are only used for WoWLAN, which can only be invoked when CONFIG_PM is set. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-17nl80211: correctly use nl80211_nan_srf_policyJohannes Berg1-1/+2
This was clearly intended to be used in the attribute parsing, so do that instead of leaving the attribute policy unused. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-13cfg80211: support virtual interfaces with different beacon intervalsPurushottam Kushwaha3-10/+49
This commit provides a mechanism for the host drivers to advertise the support for different beacon intervals among the respective interface combinations in a group, through NL80211_IFACE_COMB_BI_MIN_GCD (u32). This value will be compared against GCD of all beaconing interfaces of matching combinations. If the driver doesn't advertise this value, the old behaviour where all beacon intervals must be identical is retained. If it is specified, then any beacon interval for an interface in the interface combination as well as the GCD of all active beacon intervals in the combination must be greater or equal to this value. Signed-off-by: Purushottam Kushwaha <pkushwah@qti.qualcomm.com> [change commit message, some variable names, small other things] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-13cfg80211: pass struct to interface combination check/iterPurushottam Kushwaha1-16/+12
Move the growing parameter list to a structure for the interface combination check and iteration functions in cfg80211 and mac80211 to make the code easier to understand. Signed-off-by: Purushottam Kushwaha <pkushwah@qti.qualcomm.com> [edit commit message] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-12cfg80211: add ability to check DA/SA in A-MSDU decapsulationJohannes Berg1-2/+12
We should not accept arbitrary DA/SA inside A-MSDUs, it could be used to circumvent protections, like allowing a station to send frames and make them seem to come from somewhere else. Add the necessary infrastructure in cfg80211 to allow such checks, in further patches we'll start using them. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-12cfg80211: let ieee80211_amsdu_to_8023s() take only header-less SKBJohannes Berg1-19/+5
There's only a single case where has_80211_header is passed as true, which is in mac80211. Given that there's only simple code that needs to be done before calling it, export that function from cfg80211 instead and let mac80211 call it itself. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-04Merge remote-tracking branch 'net-next/master' into mac80211-nextJohannes Berg1-1/+1
Resolve the merge conflict between Felix's/my and Toke's patches coming into the tree through net and mac80211-next respectively. Most of Felix's changes go away due to Toke's new infrastructure work, my patch changes to "goto begin" (the label wasn't there before) instead of returning NULL so flow control towards drivers is preserved better. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-30cfg80211: Provide an API to report NAN function terminationAyala Beker1-0/+60
Provide a function that reports NAN DE function termination. The function may be terminated due to one of the following reasons: user request, ttl expiration or failure. If the NAN instance is tied to the owner, the notification will be sent to the socket that started the NAN interface only Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-30cfg80211: provide a function to report a match for NANAyala Beker1-0/+80
Provide a function the driver can call to report a match. This will send the event to the user space. If the NAN instance is tied to the owner, the notifications will be sent to the socket that started the NAN interface only. Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-30cfg80211: allow the user space to change current NAN configurationAyala Beker3-0/+83
Some NAN configuration paramaters may change during the operation of the NAN device. For example, a user may want to update master preference value when the device gets plugged/unplugged to the power. Add API that allows to do so. Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-30cfg80211: add add_nan_func / del_nan_funcAyala Beker5-1/+453
A NAN function can be either publish, subscribe or follow up. Make all the necessary verifications and just pass the request to the driver. Allow the user space application that starts NAN to forbid any other socket to add or remove functions. Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Ayala Beker <ayala.beker@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-30cfg80211: add start / stop NAN commandsAyala Beker8-5/+179
This allows user space to start/stop NAN interface. A NAN interface is like P2P device in a few aspects: it doesn't have a netdev associated to it. Add the new interface type and prevent operations that can't be executed on NAN interface like scan. Define several attributes that may be configured by user space when starting NAN functionality (master preference and dual band operation) Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-30cfg80211: Add support for static WEP in the driverDavid Spinadel6-8/+13
Add support for drivers that implement static WEP internally, i.e. expose connection keys to the driver in connect flow and don't upload the keys after the connection. Signed-off-by: David Spinadel <david.spinadel@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-28cfg80211: wext: really don't store non-WEP keysJohannes Berg1-1/+11
Jouni reported that during (repeated) wext_pmf test runs (from the wpa_supplicant hwsim test suite) the kernel crashes. The reason is that after the key is set, the wext code still unnecessarily stores it into the key cache. Despite smatch pointing out an overflow, I failed to identify the possibility for this in the code and missed it during development of the earlier patch series. In order to fix this, simply check that we never store anything but WEP keys into the cache, adding a comment as to why that's enough. Also, since the cache is still allocated early even if it won't be used in many cases, add a comment explaining why - otherwise we'd have to roll back key settings to the driver in case of allocation failures, which is far more difficult. Fixes: 89b706fb28e4 ("cfg80211: reduce connect key caching struct size") Reported-by: Jouni Malinen <j@w1.fi> Bisected-by: Jouni Malinen <j@w1.fi> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-26cfg80211: add checks for beacon rate, extend to meshJohannes Berg1-11/+35
The previous commit added support for specifying the beacon rate for AP mode. Add features checks to this, and extend it to also support the rate configuration for mesh networks. For IBSS it's not as simple due to joining etc., so that's not yet supported. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-26cfg80211: Add support to configure a beacon data ratePurushottam Kushwaha1-222/+288
This allows an option to configure a single beacon tx rate for an AP. Signed-off-by: Purushottam Kushwaha <pkushwah@qti.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
2016-09-18Merge tag 'mac80211-next-for-davem-2016-09-16' of ↵David S. Miller11-66/+130
git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next Johannes Berg says: ==================== This time we have various things - all across the board: * MU-MIMO sniffer support in mac80211 * a create_singlethread_workqueue() cleanup * interface dump filtering that was documented but not implemented * support for the new radiotap timestamp field * send delBA in two unexpected conditions (as required by the spec) * connect keys cleanups - allow only WEP with index 0-3 * per-station aggregation limit to work around broken APs * debugfs improvement for the integrated codel algorithm and various other small improvements and cleanups. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-16cfg80211: add helper to find an IE that matches a byte-arrayLuca Coelho1-31/+27
There are a few places where an IE that matches not only the EID, but also other bytes inside the element, needs to be found. To simplify that and reduce the amount of similar code, implement a new helper function to match the EID and an extra array of bytes. Additionally, simplify cfg80211_find_vendor_ie() by using the new match function. Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-15cfg80211: remove unnecessary pointer-ofJohannes Berg1-1/+1
For an array, there's no need to use &array, so just use the plain wiphy->addresses[i].addr here to silence smatch. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-15nl80211: always check nla_put* return valuesJohannes Berg1-5/+8
A few instances were found where we didn't check them, add the missing checks even though they'll probably never trigger as the message should be large enough here. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-15nl80211: always check nla_nest_start() return valueJohannes Berg1-0/+11
If the message got full during nla_nest_start(), it can return NULL. None of the cases here seem like that can really happen, but check the return value nonetheless. Signed-off-by: Johannes Berg <johannes.berg@intel.com>