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2023-12-13drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" groupIdo Schimmel
[ Upstream commit e03781879a0d524ce3126678d50a80484a513c4b ] The "NET_DM" generic netlink family notifies drop locations over the "events" multicast group. This is problematic since by default generic netlink allows non-root users to listen to these notifications. Fix by adding a new field to the generic netlink multicast group structure that when set prevents non-root users or root without the 'CAP_SYS_ADMIN' capability (in the user namespace owning the network namespace) from joining the group. Set this field for the "events" group. Use 'CAP_SYS_ADMIN' rather than 'CAP_NET_ADMIN' because of the nature of the information that is shared over this group. Note that the capability check in this case will always be performed against the initial user namespace since the family is not netns aware and only operates in the initial network namespace. A new field is added to the structure rather than using the "flags" field because the existing field uses uAPI flags and it is inappropriate to add a new uAPI flag for an internal kernel check. In net-next we can rework the "flags" field to use internal flags and fold the new field into it. But for now, in order to reduce the amount of changes, add a new field. Since the information can only be consumed by root, mark the control plane operations that start and stop the tracing as root-only using the 'GENL_ADMIN_PERM' flag. Tested using [1]. Before: # capsh -- -c ./dm_repo # capsh --drop=cap_sys_admin -- -c ./dm_repo After: # capsh -- -c ./dm_repo # capsh --drop=cap_sys_admin -- -c ./dm_repo Failed to join "events" multicast group [1] $ cat dm.c #include <stdio.h> #include <netlink/genl/ctrl.h> #include <netlink/genl/genl.h> #include <netlink/socket.h> int main(int argc, char **argv) { struct nl_sock *sk; int grp, err; sk = nl_socket_alloc(); if (!sk) { fprintf(stderr, "Failed to allocate socket\n"); return -1; } err = genl_connect(sk); if (err) { fprintf(stderr, "Failed to connect socket\n"); return err; } grp = genl_ctrl_resolve_grp(sk, "NET_DM", "events"); if (grp < 0) { fprintf(stderr, "Failed to resolve \"events\" multicast group\n"); return grp; } err = nl_socket_add_memberships(sk, grp, NFNLGRP_NONE); if (err) { fprintf(stderr, "Failed to join \"events\" multicast group\n"); return err; } return 0; } $ gcc -I/usr/include/libnl3 -lnl-3 -lnl-genl-3 -o dm_repo dm.c Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol") Reported-by: "The UK's National Cyber Security Centre (NCSC)" <security@ncsc.gov.uk> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231206213102.1824398-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-27genetlink: limit the use of validation workarounds to old opsJakub Kicinski
During review of previous change another thing came up - we should limit the use of validation workarounds to old commands. Don't list the workarounds one by one, as we're rejecting all existing ones. We can deal with the masking in the unlikely event that new flag is added. Link: https://lore.kernel.org/all/6ba9f727e555fd376623a298d5d305ad408c3d47.camel@sipsolutions.net/ Link: https://lore.kernel.org/r/20221026001524.1892202-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-24genetlink: piggy back on resv_op to default to a reject policyJakub Kicinski
To keep backward compatibility we used to leave attribute parsing to the family if no policy is specified. This becomes tedious as we move to more strict validation. Families must define reject all policies if they don't want any attributes accepted. Piggy back on the resv_start_op field as the switchover point. AFAICT only ethtool has added new commands since the resv_start_op was defined, and it has per-op policies so this should be a no-op. Nonetheless the patch should still go into v6.1 for consistency. Link: https://lore.kernel.org/all/20221019125745.3f2e7659@kernel.org/ Link: https://lore.kernel.org/r/20221021193532.1511293-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-30genetlink: reject use of nlmsg_flags for new commandsJakub Kicinski
Commit 9c5d03d36251 ("genetlink: start to validate reserved header bytes") introduced extra validation for genetlink headers. We had to gate it to only apply to new commands, to maintain bug-wards compatibility. Use this opportunity (before the new checks make it to Linus's tree) to add more conditions. Validate that Generic Netlink families do not use nlmsg_flags outside of the well-understood set. Link: https://lore.kernel.org/all/20220928073709.1b93b74a@kernel.org/ Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Link: https://lore.kernel.org/r/20220929142809.1167546-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-29genetlink: start to validate reserved header bytesJakub Kicinski
We had historically not checked that genlmsghdr.reserved is 0 on input which prevents us from using those precious bytes in the future. One use case would be to extend the cmd field, which is currently just 8 bits wide and 256 is not a lot of commands for some core families. To make sure that new families do the right thing by default put the onus of opting out of validation on existing families. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel) Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-26genetlink: hold read cb_lock during iteration of genl_fam_idr in genl_bind()Jiri Pirko
In genl_bind(), currently genl_lock and write cb_lock are taken for iteration of genl_fam_idr and processing of static values stored in struct genl_family. Take just read cb_lock for this task as it is sufficient to guard the idr and the struct against concurrent genl_register/unregister_family() calls. This will allow to run genl command processing in genl_rcv() and mnl_socket_setsockopt(.., NETLINK_ADD_MEMBERSHIP, ..) in parallel. Reported-by: Vikas Gupta <vikas.gupta@broadcom.com> Signed-off-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20220825081940.1283335-1-jiri@resnulli.us Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-18net: genl: fix error path memory leak in policy dumpingJakub Kicinski
If construction of the array of policies fails when recording non-first policy we need to unwind. netlink_policy_dump_add_policy() itself also needs fixing as it currently gives up on error without recording the allocated pointer in the pstate pointer. Reported-by: syzbot+dc54d9ba8153b216cae0@syzkaller.appspotmail.com Fixes: 50a896cf2d6f ("genetlink: properly support per-op policy dumping") Link: https://lore.kernel.org/r/20220816161939.577583-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30net: netlink: Remove unused functionYajun Deng
lockdep_genl_is_held() and its caller arm not used now, just remove them. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Link: https://lore.kernel.org/r/20210729074854.8968-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-27net: netlink: add the case when nlh is NULLYajun Deng
Add the case when nlh is NULL in nlmsg_report(), so that the caller doesn't need to deal with this case. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-12mptcp: avoid lock_fast usage in accept pathFlorian Westphal
Once event support is added this may need to allocate memory while msk lock is held with softirqs disabled. Not using lock_fast also allows to do the allocation with GFP_KERNEL. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03genetlink: allow dumping command-specific policyJakub Kicinski
Right now CTRL_CMD_GETPOLICY can only dump the family-wide policy. Support dumping policy of a specific op. v3: - rebase after per-op policy export and handle that v2: - make cmd U32, just in case. v1: - don't echo op in the output in a naive way, this should make it cleaner to extend the output format for dumping policies for all the commands at once in the future. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20201001225933.1373426-11-kuba@kernel.org Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03genetlink: properly support per-op policy dumpingJohannes Berg
Add support for per-op policy dumping. The data is pretty much as before, except that now the assumption that the policy with index 0 is "the" policy no longer holds - you now need to look at the new CTRL_ATTR_OP_POLICY attribute which is a nested attr (indexed by op) containing attributes for do and dump policies. When a single op is requested, the CTRL_ATTR_OP_POLICY will be added in the same way, since do and dump policies may differ. v2: - conditionally advertise per-command policies only if there actually is a policy being used for the do/dump and it's present at all Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03genetlink: factor skb preparation out of ctrl_dumppolicy()Johannes Berg
We'll need this later for the per-op policy index dump. Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03netlink: rework policy dump to support multiple policiesJohannes Berg
Rework the policy dump code a bit to support adding multiple policies to a single dump, in order to e.g. support per-op policies in generic netlink. v2: - move kernel-doc to implementation [Jakub] - squash the first patch to not flip-flop on the prototype [Jakub] - merge netlink_policy_dump_get_policy_idx() with the old get_policy_idx() we already had - rebase without Jakub's patch to have per-op dump Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: switch control commands to per-op policiesJakub Kicinski
In preparation for adding a new attribute to CTRL_CMD_GETPOLICY split the policies for getpolicy and getfamily apart. This will cause a slight user-visible change in that dumping the policies will switch from per family to per op, but supposedly sniffer-type applications (which are the main use case for policy dumping thus far) should support both, anyway. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: use parsed attrs in dumppolicyJakub Kicinski
Attributes are already parsed based on the policy specified in the family and ready-to-use in info->attrs. No need to call genlmsg_parse() again. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: bring back per op policyJakub Kicinski
Add policy to the struct genl_ops structure, this time with maxattr, so it can be used properly. Propagate .policy and .maxattr from the family in genl_get_cmd() if needed, this way the rest of the code does not have to worry if the policy is per op or global. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: use .start callback for dumppolicyJakub Kicinski
The structure of ctrl_dumppolicy() is clearly split into init and dumping. Move the init to a .start callback for clarity, it's a more idiomatic netlink dump code structure. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: add a structure for dump stateJakub Kicinski
Whenever netlink dump uses more than 2 cb->args[] entries code gets hard to read. We're about to add more state to ctrl_dumppolicy() so create a structure. Since the structure is typed and clearly named we can remove the local fam_id variable and use ctx->fam_id directly. v3: - rebase onto explicit free fix v1: - s/nl_policy_dump/netlink_policy_dump_state/ - forward declare struct netlink_policy_dump_state, and move from passing unsigned long to actual pointer type - add build bug on - u16 fam_id - s/args/ctx/ Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: add small version of opsJakub Kicinski
We want to add maxattr and policy back to genl_ops, to enable dumping per command policy to user space. This, however, would cause bloat for all the families with global policies. Introduce smaller version of ops (half the size of genl_ops). Translate these smaller ops into a full blown struct before use in the core. v1: - use struct assignment - put a full copy of the op in struct genl_dumpit_info - s/light/small/ Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02netlink: fix policy dump leakJohannes Berg
[ Upstream commit a95bc734e60449e7b073ff7ff70c35083b290ae9 ] If userspace doesn't complete the policy dump, we leak the allocated state. Fix this. Fixes: d07dcf9aadd6 ("netlink: add infrastructure to expose policies to userspace") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-24net: netlink: delete repeated wordsRandy Dunlap
Drop duplicated words in net/netlink/. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-06Merge tag 'thermal-v5.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux Pull thermal updates from Daniel Lezcano: - Add support to enable/disable the thermal zones resulting on core code and drivers cleanup (Andrzej Pietrasiewicz) - Add generic netlink support for userspace notifications: events, temperature and discovery commands (Daniel Lezcano) - Fix redundant initialization for a ret variable (Colin Ian King) - Remove the clock cooling code as it is used nowhere (Amit Kucheria) - Add the rcar_gen3_thermal's r8a774e1 support (Marian-Cristian Rotariu) - Replace all references to thermal.txt in the documentation to the corresponding yaml files (Amit Kucheria) - Add maintainer entry for the IPA (Lukasz Luba) - Add support for MSM8939 for the tsens (Shawn Guo) - Update power allocator and devfreq cooling to SPDX licensing (Lukasz Luba) - Add Cannon Lake Low Power PCH support (Sumeet Pawnikar) - Add tsensor support for V2 mediatek thermal system (Henry Yen) - Fix thermal zone lookup by ID for the core code (Thierry Reding) * tag 'thermal-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (40 commits) thermal: intel: intel_pch_thermal: Add Cannon Lake Low Power PCH support thermal: mediatek: Add tsensor support for V2 thermal system thermal: mediatek: Prepare to add support for other platforms thermal: Update power allocator and devfreq cooling to SPDX licensing MAINTAINERS: update entry to thermal governors file name prefixing thermal: core: Add thermal zone enable/disable notification thermal: qcom: tsens-v0_1: Add support for MSM8939 dt-bindings: tsens: qcom: Document MSM8939 compatible thermal: core: Fix thermal zone lookup by ID thermal: int340x: processor_thermal: fix: update Jasper Lake PCI id thermal: imx8mm: Support module autoloading thermal: ti-soc-thermal: Fix reversed condition in ti_thermal_expose_sensor() MAINTAINERS: Add maintenance information for IPA thermal: rcar_gen3_thermal: Do not shadow thcode variable dt-bindings: thermal: Get rid of thermal.txt and replace references thermal: core: Move initialization after core initcall thermal: netlink: Improve the initcall ordering net: genetlink: Move initialization to core_initcall thermal: rcar_gen3_thermal: Add r8a774e1 support thermal/drivers/clock_cooling: Remove clock_cooling code ...
2020-07-21net: genetlink: Move initialization to core_initcallDaniel Lezcano
The generic netlink is initialized far after the netlink protocol itself at subsys_initcall. The devlink is initialized at the same level, but after, as shown by a disassembly of the vmlinux: [ ... ] 374 ffff8000115f22c0 <__initcall_devlink_init4>: 375 ffff8000115f22c4 <__initcall_genl_init4>: [ ... ] The function devlink_init() calls genl_register_family() before the generic netlink subsystem is initialized. As the generic netlink initcall level is set since 2005, it seems that was not a problem, but now we have the thermal framework initialized at the core_initcall level which creates the generic netlink family and sends a notification which leads to a subtle memory corruption only detectable when the CONFIG_INIT_ON_ALLOC_DEFAULT_ON option is set with the earlycon at init time. The thermal framework needs to be initialized early in order to begin the mitigation as soon as possible. Moving it to postcore_initcall is acceptable. This patch changes the initialization level for the generic netlink family to the core_initcall and comes after the netlink protocol initialization. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org> Link: https://lore.kernel.org/r/20200715074120.8768-1-daniel.lezcano@linaro.org
2020-07-01genetlink: remove genl_bindSean Tranchetti
A potential deadlock can occur during registering or unregistering a new generic netlink family between the main nl_table_lock and the cb_lock where each thread wants the lock held by the other, as demonstrated below. 1) Thread 1 is performing a netlink_bind() operation on a socket. As part of this call, it will call netlink_lock_table(), incrementing the nl_table_users count to 1. 2) Thread 2 is registering (or unregistering) a genl_family via the genl_(un)register_family() API. The cb_lock semaphore will be taken for writing. 3) Thread 1 will call genl_bind() as part of the bind operation to handle subscribing to GENL multicast groups at the request of the user. It will attempt to take the cb_lock semaphore for reading, but it will fail and be scheduled away, waiting for Thread 2 to finish the write. 4) Thread 2 will call netlink_table_grab() during the (un)registration call. However, as Thread 1 has incremented nl_table_users, it will not be able to proceed, and both threads will be stuck waiting for the other. genl_bind() is a noop, unless a genl_family implements the mcast_bind() function to handle setting up family-specific multicast operations. Since no one in-tree uses this functionality as Cong pointed out, simply removing the genl_bind() function will remove the possibility for deadlock, as there is no attempt by Thread 1 above to take the cb_lock semaphore. Fixes: c380d9a7afff ("genetlink: pass multicast bind/unbind to families") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Johannes Berg <johannes.berg@intel.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sean Tranchetti <stranche@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29genetlink: get rid of family->attrbufCong Wang
genl_family_rcv_msg_attrs_parse() reuses the global family->attrbuf when family->parallel_ops is false. However, family->attrbuf is not protected by any lock on the genl_family_rcv_msg_doit() code path. This leads to several different consequences, one of them is UAF, like the following: genl_family_rcv_msg_doit(): genl_start(): genl_family_rcv_msg_attrs_parse() attrbuf = family->attrbuf __nlmsg_parse(attrbuf); genl_family_rcv_msg_attrs_parse() attrbuf = family->attrbuf __nlmsg_parse(attrbuf); info->attrs = attrs; cb->data = info; netlink_unicast_kernel(): consume_skb() genl_lock_dumpit(): genl_dumpit_info(cb)->attrs Note family->attrbuf is an array of pointers to the skb data, once the skb is freed, any dereference of family->attrbuf will be a UAF. Maybe we could serialize the family->attrbuf with genl_mutex too, but that would make the locking more complicated. Instead, we can just get rid of family->attrbuf and always allocate attrbuf from heap like the family->parallel_ops==true code path. This may add some performance overhead but comparing with taking the global genl_mutex, it still looks better. Fixes: 75cdbdd08900 ("net: ieee802154: have genetlink code to parse the attrs during dumpit") Fixes: 057af7071344 ("net: tipc: have genetlink code to parse the attrs during dumpit") Reported-and-tested-by: syzbot+3039ddf6d7b13daf3787@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+80cad1e3cb4c41cde6ff@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+736bcbcb11b60d0c0792@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+520f8704db2b68091d44@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+c96e4dfb32f8987fdeed@syzkaller.appspotmail.com Cc: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-12genetlink: clean up family attributes allocationsCong Wang
genl_family_rcv_msg_attrs_parse() and genl_family_rcv_msg_attrs_free() take a boolean parameter to determine whether allocate/free the family attrs. This is unnecessary as we can just check family->parallel_ops. More importantly, callers would not need to worry about pairing these parameters correctly after this patch. And this fixes a memory leak, as after commit c36f05559104 ("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()") we call genl_family_rcv_msg_attrs_parse() for both parallel and non-parallel cases. Fixes: c36f05559104 ("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()") Reported-by: Ido Schimmel <idosch@idosch.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Tested-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-04genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()Cong Wang
There are two kinds of memory leaks in genl_family_rcv_msg_dumpit(): 1. Before we call ops->start(), whenever an error happens, we forget to free the memory allocated in genl_family_rcv_msg_dumpit(). 2. When ops->start() fails, the 'info' has been already installed on the per socket control block, so we should not free it here. More importantly, nlk->cb_running is still false at this point, so netlink_sock_destruct() cannot free it either. The first kind of memory leaks is easier to resolve, but the second one requires some deeper thoughts. After reviewing how netfilter handles this, the most elegant solution I find is just to use a similar way to allocate the memory, that is, moving memory allocations from caller into ops->start(). With this, we can solve both kinds of memory leaks: for 1), no memory allocation happens before ops->start(); for 2), ops->start() handles its own failures and 'info' is installed to the socket control block only when success. The only ugliness here is we have to pass all local variables on stack via a struct, but this is not hard to understand. Alternatively, we can introduce a ops->free() to solve this too, but it is overkill as only genetlink has this problem so far. Fixes: 1927f41a22a0 ("net: genetlink: introduce dump info struct to be available during dumpit op") Reported-by: syzbot+21f04f481f449c8db840@syzkaller.appspotmail.com Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Florian Westphal <fw@strlen.de> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Jiri Pirko <jiri@mellanox.com> Cc: YueHaibing <yuehaibing@huawei.com> Cc: Shaochun Chen <cscnull@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30netlink: add infrastructure to expose policies to userspaceJohannes Berg
Add, and use in generic netlink, helpers to dump out a netlink policy to userspace, including all the range validation data, nested policies etc. This lets userspace discover what the kernel understands. For families/commands other than generic netlink, the helpers need to be used directly in an appropriate command, or we can add some infrastructure (a new netlink family) that those can register their policies with for introspection. I'm not that familiar with non-generic netlink, so that's left out for now. The data exposed to userspace also includes min and max length for binary/string data, I've done that instead of letting the userspace tools figure out whether min/max is intended based on the type so that we can extend this later in the kernel, we might want to just use the range data for example. Because of this, I opted to not directly expose the NLA_* values, even if some of them are already exposed via BPF, as with min/max length we don't need to have different types here for NLA_BINARY/NLA_MIN_LEN/NLA_EXACT_LEN, we just make them all NL_ATTR_TYPE_BINARY with min/max length optionally set. Similarly, we don't really need NLA_MSECS, and perhaps can remove it in the future - but not if we encode it into the userspace API now. It gets mapped to NL_ATTR_TYPE_U64 here. Note that the exposing here corresponds to the strict policy interpretation, and NLA_UNSPEC items are omitted entirely. To get those, change them to NLA_MIN_LEN which behaves in exactly the same way, but is exposed. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-22net: genetlink: return the error code when attribute parsing fails.Paolo Abeni
Currently if attribute parsing fails and the genl family does not support parallel operation, the error code returned by __nlmsg_parse() is discarded by genl_family_rcv_msg_attrs_parse(). Be sure to report the error for all genl families. Fixes: c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to a separate function") Fixes: ab5b526da048 ("net: genetlink: always allocate separate attrs for dumpit ops") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13genetlink: do not parse attributes for families with zero maxattrMichal Kubecek
Commit c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to a separate function") moved attribute buffer allocation and attribute parsing from genl_family_rcv_msg_doit() into a separate function genl_family_rcv_msg_attrs_parse() which, unlike the previous code, calls __nlmsg_parse() even if family->maxattr is 0 (i.e. the family does its own parsing). The parser error is ignored and does not propagate out of genl_family_rcv_msg_attrs_parse() but an error message ("Unknown attribute type") is set in extack and if further processing generates no error or warning, it stays there and is interpreted as a warning by userspace. Dumpit requests are not affected as genl_family_rcv_msg_dumpit() bypasses the call of genl_family_rcv_msg_attrs_parse() if family->maxattr is zero. Move this logic inside genl_family_rcv_msg_attrs_parse() so that we don't have to handle it in each caller. v3: put the check inside genl_family_rcv_msg_attrs_parse() v2: adjust also argument of genl_family_rcv_msg_attrs_free() Fixes: c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to a separate function") Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-08net: genetlink: always allocate separate attrs for dumpit opsJiri Pirko
Individual dumpit ops (start, dumpit, done) are locked by genl_lock if !family->parallel_ops. However, multiple genl_family_rcv_msg_dumpit() calls may in in flight in parallel. Each has a separate struct genl_dumpit_info allocated but they share the same family->attrbuf. Fix this by allocating separate memory for attrs for dumpit ops, for non-parallel_ops (for parallel_ops it is done already). Reported-by: syzbot+495688b736534bb6c6ad@syzkaller.appspotmail.com Reported-by: syzbot+ff59dc711f2cff879a05@syzkaller.appspotmail.com Reported-by: syzbot+dbe02e13bcce52bcf182@syzkaller.appspotmail.com Reported-by: syzbot+9cb7edb2906ea1e83006@syzkaller.appspotmail.com Fixes: bf813b0afeae ("net: genetlink: parse attrs and store in contect info struct during dumpit") Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-06net: genetlink: remove unused genl_family_attrbuf()Jiri Pirko
genl_family_attrbuf() function is no longer used by anyone, so remove it. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-06net: genetlink: parse attrs and store in contect info struct during dumpitJiri Pirko
Extend the dumpit info struct for attrs. Instead of existing attribute validation do parse them and save in the info struct. Caller can benefit from this and does not have to do parse itself. In order to properly free attrs, genl_family pointer needs to be added to dumpit info struct as well. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-06net: genetlink: push attrbuf allocation and parsing to a separate functionJiri Pirko
To be re-usable by dumpit as well, push the code that is taking care of attrbuf allocation and parting from doit into separate function. Introduce a helper to free the buffer too. Check family->maxattr too before calling kfree() to be symmetrical with the allocation check. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-06net: genetlink: introduce dump info struct to be available during dumpit opJiri Pirko
Currently the cb->data is taken by ops during non-parallel dumping. Introduce a new structure genl_dumpit_info and store the ops there. Distribute the info to both non-parallel and parallel dumping. Also add a helper genl_dumpit_info() to easily get the info structure in the dumpit callback from cb. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-06net: genetlink: push doit/dumpit code from genl_family_rcv_msgJiri Pirko
Currently the function genl_family_rcv_msg() is quite big. Since it is quite convenient, push code that is related to doit and dumpit ops into separate functions. Do small changes on the way, like rc/err unification, NULL check etc. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-04genetlink: do not validate dump requests if there is no policyMichal Kubecek
Unlike do requests, dump genetlink requests now perform strict validation by default even if the genetlink family does not set policy and maxtype because it does validation and parsing on its own (e.g. because it wants to allow different message format for different commands). While the null policy will be ignored, maxtype (which would be zero) is still checked so that any attribute will fail validation. The solution is to only call __nla_validate() from genl_family_rcv_msg() if family->maxtype is set. Fixes: ef6243acb478 ("genetlink: optionally validate strictly/dumps") Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Three trivial overlapping conflicts. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27genetlink: optionally validate strictly/dumpsJohannes Berg
Add options to strictly validate messages and dump messages, sometimes perhaps validating dump messages non-strictly may be required, so add an option for that as well. Since none of this can really be applied to existing commands, set the options everwhere using the following spatch: @@ identifier ops; expression X; @@ struct genl_ops ops[] = { ..., { .cmd = X, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, ... }, ... }; For new commands one should just not copy the .validate 'opt-out' flags and thus get strict validation. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg
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>
2019-04-27netlink: make nla_nest_start() add NLA_F_NESTED flagMichal Kubecek
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>
2019-04-26genetlink: use idr_alloc_cyclic for family->id assignmentMarcel Holtmann
When allocating the next family->id it makes more sense to use idr_alloc_cyclic to avoid re-using a previously used family->id as much as possible. Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2019-03-22genetlink: make policy common to familyJohannes Berg
Since maxattr is common, the policy can't really differ sanely, so make it common as well. The only user that did in fact manage to make a non-common policy is taskstats, which has to be really careful about it (since it's still using a common maxattr!). This is no longer supported, but we can fake it using pre_doit. This reduces the size of e.g. nl80211.o (which has lots of commands): text data bss dec hex filename 398745 14323 2240 415308 6564c net/wireless/nl80211.o (before) 397913 14331 2240 414484 65314 net/wireless/nl80211.o (after) -------------------------------- -832 +8 0 -824 Which is obviously just 8 bytes for each command, and an added 8 bytes for the new policy pointer. I'm not sure why the ops list is counted as .text though. Most of the code transformations were done using the following spatch: @ops@ identifier OPS; expression POLICY; @@ struct genl_ops OPS[] = { ..., { - .policy = POLICY, }, ... }; @@ identifier ops.OPS; expression ops.POLICY; identifier fam; expression M; @@ struct genl_family fam = { .ops = OPS, .maxattr = M, + .policy = POLICY, ... }; This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing the cb->data as ops, which we want to change in a later genl patch. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-21genetlink: Fix a memory leak on error pathYueHaibing
In genl_register_family(), when idr_alloc() fails, we forget to free the memory we possibly allocate for family->attrbuf. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 2ae0f17df1cd ("genetlink: use idr to track families") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-03-16netlink: avoid a double skb free in genlmsg_mcast()Nicolas Dichtel
nlmsg_multicast() consumes always the skb, thus the original skb must be freed only when this function is called with a clone. Fixes: cb9f7a9a5c96 ("netlink: ensure to loop over all netns in genlmsg_multicast_allns()") Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-08netlink: ensure to loop over all netns in genlmsg_multicast_allns()Nicolas Dichtel
Nowadays, nlmsg_multicast() returns only 0 or -ESRCH but this was not the case when commit 134e63756d5f was pushed. However, there was no reason to stop the loop if a netns does not have listeners. Returns -ESRCH only if there was no listeners in all netns. To avoid having the same problem in the future, I didn't take the assumption that nlmsg_multicast() returns only 0 or -ESRCH. Fixes: 134e63756d5f ("genetlink: make netns aware") CC: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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>