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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-13netlink: pass extended ACK struct where availableJohannes Berg1-1/+1
This is an add-on to the previous patch that passes the extended ACK structure where it's already available by existing genl_info or extack function arguments. This was done with this spatch (with some manual adjustment of indentation): @@ expression A, B, C, D, E; identifier fn, info; @@ fn(..., struct genl_info *info, ...) { ... -nlmsg_parse(A, B, C, D, E, NULL) +nlmsg_parse(A, B, C, D, E, info->extack) ... } @@ expression A, B, C, D, E; identifier fn, info; @@ fn(..., struct genl_info *info, ...) { <... -nla_parse_nested(A, B, C, D, NULL) +nla_parse_nested(A, B, C, D, info->extack) ...> } @@ expression A, B, C, D, E; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nlmsg_parse(A, B, C, D, E, NULL) +nlmsg_parse(A, B, C, D, E, extack) ...> } @@ expression A, B, C, D, E; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_parse(A, B, C, D, E, NULL) +nla_parse(A, B, C, D, E, extack) ...> } @@ expression A, B, C, D, E; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { ... -nlmsg_parse(A, B, C, D, E, NULL) +nlmsg_parse(A, B, C, D, E, extack) ... } @@ expression A, B, C, D; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_parse_nested(A, B, C, D, NULL) +nla_parse_nested(A, B, C, D, extack) ...> } @@ expression A, B, C, D; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nlmsg_validate(A, B, C, D, NULL) +nlmsg_validate(A, B, C, D, extack) ...> } @@ expression A, B, C, D; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_validate(A, B, C, D, NULL) +nla_validate(A, B, C, D, extack) ...> } @@ expression A, B, C; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_validate_nested(A, B, C, NULL) +nla_validate_nested(A, B, C, extack) ...> } Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg1-1/+1
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13genetlink: pass extended ACK report downJohannes Berg1-2/+4
Pass the extended ACK reporting struct down from generic netlink to the families, using the existing struct genl_info for simplicity. Also add support to set the extended ACK information from generic netlink users. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: extended ACK reportingJohannes Berg1-1/+2
Add the base infrastructure and UAPI for netlink extended ACK reporting. All "manual" calls to netlink_ack() pass NULL for now and thus don't get extended ACK reporting. Big thanks goes to Pablo Neira Ayuso for not only bringing up the whole topic at netconf (again) but also coming up with the nlattr passing trick and various other ideas. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22genetlink: fix counting regression on ctrl_dumpfamily()Stanislaw Gruszka1-1/+3
Commit 2ae0f17df1cd ("genetlink: use idr to track families") replaced if (++n < fams_to_skip) continue; into: if (n++ < fams_to_skip) continue; This subtle change cause that on retry ctrl_dumpfamily() call we omit one family that failed to do ctrl_fill_info() on previous call, because cb->args[0] = n number counts also family that failed to do ctrl_fill_info(). Patch fixes the problem and avoid confusion in the future just decrease n counter when ctrl_fill_info() fail. User visible problem caused by this bug is failure to get access to some genetlink family i.e. nl80211. However problem is reproducible only if number of registered genetlink families is big enough to cause second call of ctrl_dumpfamily(). Cc: Xose Vazquez Perez <xose.vazquez@gmail.com> Cc: Larry Finger <Larry.Finger@lwfinger.net> Cc: Johannes Berg <johannes@sipsolutions.net> Fixes: 2ae0f17df1cd ("genetlink: use idr to track families") Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
Several cases of bug fixes in 'net' overlapping other changes in 'net-next-. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03genetlink: fix a memory leak on error pathWANG Cong1-1/+3
In __genl_register_family(), when genl_validate_assign_mc_groups() fails, we forget to free the memory we possibly allocate for family->attrbuf. Note, some callers call genl_unregister_family() to clean up on error path, it doesn't work because the family is inserted to the global list in the nearly last step. Cc: Jakub Kicinski <kubakici@wp.pl> Cc: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-01genetlink: fix error return code in genl_register_family()Wei Yongjun1-1/+3
Fix to return a negative error code from the idr_alloc() error handling case instead of 0, as done elsewhere in this function. Also fix the return value check of idr_alloc() since idr_alloc return negative errors on failure, not zero. Fixes: 2ae0f17df1cd ("genetlink: use idr to track families") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29genetlink: Fix generic netlink family unregisterpravin shelar1-1/+1
This patch fixes a typo in unregister operation. Following crash is fixed by this patch. It can be easily reproduced by repeating modprobe and rmmod module that uses genetlink. [ 261.446686] BUG: unable to handle kernel paging request at ffffffffa0264088 [ 261.448921] IP: [<ffffffff813cb70e>] strcmp+0xe/0x30 [ 261.450494] PGD 1c09067 [ 261.451266] PUD 1c0a063 [ 261.452091] PMD 8068d5067 [ 261.452525] PTE 0 [ 261.453164] [ 261.453618] Oops: 0000 [#1] SMP [ 261.454577] Modules linked in: openvswitch(+) ... [ 261.480753] RIP: 0010:[<ffffffff813cb70e>] [<ffffffff813cb70e>] strcmp+0xe/0x30 [ 261.483069] RSP: 0018:ffffc90003c0bc28 EFLAGS: 00010282 [ 261.510145] Call Trace: [ 261.510896] [<ffffffff816f10ca>] genl_family_find_byname+0x5a/0x70 [ 261.512819] [<ffffffff816f2319>] genl_register_family+0xb9/0x630 [ 261.514805] [<ffffffffa02840bc>] dp_init+0xbc/0x120 [openvswitch] [ 261.518268] [<ffffffff8100217d>] do_one_initcall+0x3d/0x160 [ 261.525041] [<ffffffff811808a9>] do_init_module+0x60/0x1f1 [ 261.526754] [<ffffffff8110687f>] load_module+0x22af/0x2860 [ 261.530144] [<ffffffff81107026>] SYSC_finit_module+0x96/0xd0 [ 261.531901] [<ffffffff8110707e>] SyS_finit_module+0xe/0x10 [ 261.533605] [<ffffffff8100391e>] do_syscall_64+0x6e/0x180 [ 261.535284] [<ffffffff817c2faf>] entry_SYSCALL64_slow_path+0x25/0x25 [ 261.546512] RIP [<ffffffff813cb70e>] strcmp+0xe/0x30 [ 261.550198] ---[ end trace 76505a814dd68770 ]--- Fixes: 2ae0f17df1c ("genetlink: use idr to track families"). Reported-by: Jarno Rajahalme <jarno@ovn.org> CC: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Pravin B Shelar <pshelar@ovn.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27genetlink: mark families as __ro_after_initJohannes Berg1-1/+1
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: use idr to track familiesJohannes Berg1-165/+106
Since generic netlink family IDs are small integers, allocated densely, IDR is an ideal match for lookups. Replace the existing hand-written hash-table with IDR for allocation and lookup. This lets the families only be written to once, during register, since the list_head can be removed and removal of a family won't cause any writes. It also slightly reduces the code size (by about 1.3k on x86-64). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27genetlink: statically initialize familiesJohannes Berg1-15/+20
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 Berg1-15/+22
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 Berg1-0/+19
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>
2016-09-01net: make genetlink ctrl ops conststephen hemminger1-2/+2
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18Revert "genl: Add genlmsg_new_unicast() for unicast message allocation"Florian Westphal1-21/+0
This reverts commit bb9b18fb55b0 ("genl: Add genlmsg_new_unicast() for unicast message allocation")'. Nothing wrong with it; its no longer needed since this was only for mmapped netlink support. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11openvswitch: allow management from inside user namespacesTycho Andersen1-0/+4
Operations with the GENL_ADMIN_PERM flag fail permissions checks because this flag means we call netlink_capable, which uses the init user ns. Instead, let's introduce a new flag, GENL_UNS_ADMIN_PERM for operations which should be allowed inside a user namespace. The motivation for this is to be able to run openvswitch in unprivileged containers. I've tested this and it seems to work, but I really have no idea about the security consequences of this patch, so thoughts would be much appreciated. v2: use the GENL_UNS_ADMIN_PERM flag instead of a check in each function v3: use separate ifs for UNS_ADMIN_PERM and ADMIN_PERM, instead of one massive one Reported-by: James Page <james.page@canonical.com> Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com> CC: Eric Biederman <ebiederm@xmission.com> CC: Pravin Shelar <pshelar@ovn.org> CC: Justin Pettit <jpettit@nicira.com> CC: "David S. Miller" <davem@davemloft.net> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-13genetlink: Fix off-by-one in genl_allocate_reserve_groups()David S. Miller1-1/+1
The bug fix for adding n_groups to the computation forgot to adjust ">=" to ">" to keep the condition correct. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linuxDavid S. Miller1-0/+16
2016-01-12net: netlink: Fix multicast group storage allocation for families with more ↵Matti Vaittinen1-1/+1
than one groups Multicast groups are stored in global buffer. Check for needed buffer size incorrectly compares buffer size to first id for family. This means that for families with more than one mcast id one may allocate too small buffer and end up writing rest of the groups to some unallocated memory. Fix the buffer size check to compare allocated space to last mcast id for the family. Tested on ARM using kernel 3.14 Signed-off-by: Matti Vaittinen <matti.vaittinen@nokia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15netlink: add a start callback for starting a netlink dumpTom Herbert1-0/+16
The start callback allows the caller to set up a context for the dump callbacks. Presumably, the context can then be destroyed in the done callback. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-09net/netlink: lockdep_genl_is_held can be booleanYaowei Bai1-1/+1
This patch makes lockdep_genl_is_held return bool to improve readability due to this particular function only using either one or zero as its return value. No functional change. Signed-off-by: Yaowei Bai <bywxiaobai@163.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24genetlink: simplify genl_notifyJiri Benc1-6/+6
The genl_notify function has too many arguments for no real reason - all callers use genl_info to get them anyway. Just pass the genl_info down to genl_notify. Signed-off-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-8/+10
Conflicts: arch/arm/boot/dts/imx6sx-sdb.dts net/sched/cls_bpf.c Two simple sets of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18netlink: make nlmsg_end() and genlmsg_end() voidJohannes Berg1-2/+4
Contrary to common expectations for an "int" return, these functions return only a positive value -- if used correctly they cannot even return 0 because the message header will necessarily be in the skb. This makes the very common pattern of if (genlmsg_end(...) < 0) { ... } be a whole bunch of dead code. Many places also simply do return nlmsg_end(...); and the caller is expected to deal with it. This also commonly (at least for me) causes errors, because it is very common to write if (my_function(...)) /* error condition */ and if my_function() does "return nlmsg_end()" this is of course wrong. Additionally, there's not a single place in the kernel that actually needs the message length returned, and if anyone needs it later then it'll be very easy to just use skb->len there. Remove this, and make the functions void. This removes a bunch of dead code as described above. The patch adds lines because I did - return nlmsg_end(...); + nlmsg_end(...); + return 0; I could have preserved all the function's return values by returning skb->len, but instead I've audited all the places calling the affected functions and found that none cared. A few places actually compared the return value with <= 0 in dump functionality, but that could just be changed to < 0 with no change in behaviour, so I opted for the more efficient version. One instance of the error I've made numerous times now is also present in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't check for <0 or <=0 and thus broke out of the loop every single time. I've preserved this since it will (I think) have caused the messages to userspace to be formatted differently with just a single message for every SKB returned to userspace. It's possible that this isn't needed for the tools that actually use this, but I don't even know what they are so couldn't test that changing this behaviour would be acceptable. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-16genetlink: synchronize socket closing and family removalJohannes Berg1-7/+9
In addition to the problem Jeff Layton reported, I looked at the code and reproduced the same warning by subscribing and removing the genl family with a socket still open. This is a fairly tricky race which originates in the fact that generic netlink allows the family to go away while sockets are still open - unlike regular netlink which has a module refcount for every open socket so in general this cannot be triggered. Trying to resolve this issue by the obvious locking isn't possible as it will result in deadlocks between unregistration and group unbind notification (which incidentally lockdep doesn't find due to the home grown locking in the netlink table.) To really resolve this, introduce a "closing socket" reference counter (for generic netlink only, as it's the only affected family) in the core netlink code and use that in generic netlink to wait for all the sockets that are being closed at the same time as a generic netlink family is removed. This fixes the race that when a socket is closed, it will should call the unbind, but if the family is removed at the same time the unbind will not find it, leading to the warning. The real problem though is that in this case the unbind could actually find a new family that is registered to have a multicast group with the same ID, and call its mcast_unbind() leading to confusing. Also remove the warning since it would still trigger, but is now no longer a problem. This also moves the code in af_netlink.c to before unreferencing the module to avoid having the same problem in the normal non-genl case. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-16genetlink: disallow subscribing to unknown mcast groupsJohannes Berg1-1/+1
Jeff Layton reported that he could trigger the multicast unbind warning in generic netlink using trinity. I originally thought it was a race condition between unregistering the generic netlink family and closing the socket, but there's a far simpler explanation: genetlink currently allows subscribing to groups that don't (yet) exist, and the warning is triggered when unsubscribing again while the group still doesn't exist. Originally, I had a warning in the subscribe case and accepted it out of userspace API concerns, but the warning was of course wrong and removed later. However, I now think that allowing userspace to subscribe to groups that don't exist is wrong and could possibly become a security problem: Consider a (new) genetlink family implementing a permission check in the mcast_bind() function similar to the like the audit code does today; it would be possible to bypass the permission check by guessing the ID and subscribing to the group it exists. This is only possible in case a family like that would be dynamically loaded, but it doesn't seem like a huge stretch, for example wireless may be loaded when you plug in a USB device. To avoid this reject such subscription attempts. If this ends up causing userspace issues we may need to add a workaround in af_netlink to deny such requests but not return an error. Reported-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-29genetlink: A genl_bind() to an out-of-range multicast group should not WARN().David S. Miller1-6/+1
Users can request to bind to arbitrary multicast groups, so warning when the requested group number is out of range is not appropriate. And with the warning removed, and the 'err' variable properly given an initial value, we can remove 'found' altogether. Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-27netlink/genetlink: pass network namespace to bind/unbindJohannes Berg1-5/+7
Netlink families can exist in multiple namespaces, and for the most part multicast subscriptions are per network namespace. Thus it only makes sense to have bind/unbind notifications per network namespace. To achieve this, pass the network namespace of a given client socket to the bind/unbind functions. Also do this in generic netlink, and there also make sure that any bind for multicast groups that only exist in init_net is rejected. This isn't really a problem if it is accepted since a client in a different namespace will never receive any notifications from such a group, but it can confuse the family if not rejected (it's also possible to silently (without telling the family) accept it, but it would also have to be ignored on unbind so families that take any kind of action on bind/unbind won't do unnecessary work for invalid clients like that. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-27genetlink: pass multicast bind/unbind to familiesJohannes Berg1-0/+59
In order to make the newly fixed multicast bind/unbind functionality in generic netlink, pass them down to the appropriate family. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-02genetlink: remove superfluous assignmentDenis ChengRq1-5/+1
the local variable ops and n_ops were just read out from family, and not changed, hence no need to assign back. Validation functions should operate on const parameters and not change anything. Signed-off-by: Cheng Renquan <crquan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-24net: Use netlink_ns_capable to verify the permisions of netlink messagesEric W. Biederman1-1/+1
It is possible by passing a netlink socket to a more privileged executable and then to fool that executable into writing to the socket data that happens to be valid netlink message to do something that privileged executable did not intend to do. To keep this from happening replace bare capable and ns_capable calls with netlink_capable, netlink_net_calls and netlink_ns_capable calls. Which act the same as the previous calls except they verify that the opener of the socket had the desired permissions as well. Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-06Merge branch 'master' of ↵David S. Miller1-0/+21
git://git.kernel.org/pub/scm/linux/kernel/git/jesse/openvswitch Jesse Gross says: ==================== [GIT net-next] Open vSwitch Open vSwitch changes for net-next/3.14. Highlights are: * Performance improvements in the mechanism to get packets to userspace using memory mapped netlink and skb zero copy where appropriate. * Per-cpu flow stats in situations where flows are likely to be shared across CPUs. Standard flow stats are used in other situations to save memory and allocation time. * A handful of code cleanups and rationalization. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-06genl: Add genlmsg_new_unicast() for unicast message allocationThomas Graf1-0/+21
Allocates a new sk_buff large enough to cover the specified payload plus required Netlink headers. Will check receiving socket for memory mapped i/o capability and use it if enabled. Will fall back to non-mapped skb if message size exceeds the frame size of the ring. Signed-of-by: Thomas Graf <tgraf@suug.ch> Reviewed-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-11-28genetlink/pmcraid: use proper genetlink multicast APIJohannes Berg1-2/+9
The pmcraid driver is abusing the genetlink API and is using its family ID as the multicast group ID, which is invalid and may belong to somebody else (and likely will.) Make it use the correct API, but since this may already be used as-is by userspace, reserve a family ID for this code and also reserve that group ID to not break userspace assumptions. My previous patch broke event delivery in the driver as I missed that it wasn't using the right API and forgot to update it later in my series. While changing this, I noticed that the genetlink code could use the static group ID instead of a strcmp(), so also do that for the VFS_DQUOT family. Cc: Anil Ravindranath <anil_ravindranath@pmc-sierra.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-28genetlink: Fix uninitialized variable in genl_validate_assign_mc_groups()Geert Uytterhoeven1-1/+1
net/netlink/genetlink.c: In function ‘genl_validate_assign_mc_groups’: net/netlink/genetlink.c:217: warning: ‘err’ may be used uninitialized in this function Commit 2a94fe48f32ccf7321450a2cc07f2b724a444e5b ("genetlink: make multicast groups const, prevent abuse") split genl_register_mc_group() in multiple functions, but dropped the initialization of err. Initialize err to zero to fix this. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-21genetlink: fix genlmsg_multicast() bugJohannes Berg1-2/+2
Unfortunately, I introduced a tremendously stupid bug into genlmsg_multicast() when doing all those multicast group changes: it adjusts the group number, but then passes it to genlmsg_multicast_netns() which does that again. Somehow, my tests failed to catch this, so add a warning into genlmsg_multicast_netns() and remove the offending group ID adjustment. Also add a warning to the similar code in other functions so people who misuse them are more loudly warned. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: make multicast groups const, prevent abuseJohannes Berg1-112/+166
Register generic netlink multicast groups as an array with the family and give them contiguous group IDs. Then instead of passing the global group ID to the various functions that send messages, pass the ID relative to the family - for most families that's just 0 because the only have one group. This avoids the list_head and ID in each group, adding a new field for the mcast group ID offset to the family. At the same time, this allows us to prevent abusing groups again like the quota and dropmon code did, since we can now check that a family only uses a group it owns. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: pass family to functions using groupsJohannes Berg1-5/+7
This doesn't really change anything, but prepares for the next patch that will change the APIs to pass the group ID within the family, rather than the global group ID. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: remove family pointer from genl_multicast_groupJohannes Berg1-20/+18
There's no reason to have the family pointer there since it can just be passed internally where needed, so remove it. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: remove genl_unregister_mc_group()Johannes Berg1-23/+0
There are no users of this API remaining, and we'll soon change group registration to be static (like ops are now) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19quota/genetlink: use proper genetlink multicast APIsJohannes Berg1-2/+8
The quota code is abusing the genetlink API and is using its family ID as the multicast group ID, which is invalid and may belong to somebody else (and likely will.) Make the quota code use the correct API, but since this is already used as-is by userspace, reserve a family ID for this code and also reserve that group ID to not break userspace assumptions. Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19drop_monitor/genetlink: use proper genetlink multicast APIsJohannes Berg1-3/+10
The drop monitor code is abusing the genetlink API and is statically using the generic netlink multicast group 1, even if that group belongs to somebody else (which it invariably will, since it's not reserved.) Make the drop monitor code use the proper APIs to reserve a group ID, but also reserve the group id 1 in generic netlink code to preserve the userspace API. Since drop monitor can be a module, don't clear the bit for it on unregistration. Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: only pass array to genl_register_family_with_ops()Johannes Berg1-6/+8
As suggested by David Miller, make genl_register_family_with_ops() a macro and pass only the array, evaluating ARRAY_SIZE() in the macro, this is a little safer. The openvswitch has some indirection, assing ops/n_ops directly in that code. This might ultimately just assign the pointers in the family initializations, saving the struct genl_family_and_ops and code (once mcast groups are handled differently.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-18genetlink: rename shadowed variableJohannes Berg1-5/+5
Sparse pointed out that the new flags variable I had added shadowed an existing one, rename the new one to avoid that, making the code clearer. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-15genetlink: unify registration functionsJohannes Berg1-37/+16
Now that the ops assignment is just two variables rather than a long list iteration etc., there's no reason to separately export __genl_register_family() and __genl_register_family_with_ops(). Unify the two functions into __genl_register_family() and make genl_register_family_with_ops() call it after assigning the ops. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14genetlink: allow making ops constJohannes Berg1-15/+21
Allow making the ops array const by not modifying the ops flags on registration but rather only when ops are sent out in the family information. No users are updated yet except for the pre_doit/post_doit calls in wireless (the only ones that exist now.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14genetlink: register family ops as arrayJohannes Berg1-45/+33
Instead of using a linked list, use an array. This reduces the data size needed by the users of genetlink, for example in wireless (net/wireless/nl80211.c) on 64-bit it frees up over 1K of data space. Remove the attempted sending of CTRL_CMD_NEWOPS ctrl event since genl_ctrl_event(CTRL_CMD_NEWOPS, ...) only returns -EINVAL anyway, therefore no such event could ever be sent. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14genetlink: remove genl_register_ops/genl_unregister_opsJohannes Berg1-56/+1
genl_register_ops() is still needed for internal registration, but is no longer available to users of the API. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>