kernel/linux.git/include/net/genetlink.h, branch v5.18.16

mptcp: avoid lock_fast usage in accept path

2021-02-13T00:31:46+00:00

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 Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-10-06T01:40:01+00:00

Rejecting non-native endian BTF overlapped with the addition of support for it. The rest were more simple overlapping changes, except the renesas ravb binding update, which had to follow a file move as well as a YAML conversion. Signed-off-by: David S. Miller

genetlink: bring back per op policy

2020-10-03T02:11:12+00:00

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 Reviewed-by: Johannes Berg Signed-off-by: David S. Miller

genetlink: add small version of ops

2020-10-03T02:11:11+00:00

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 Reviewed-by: Johannes Berg Signed-off-by: David S. Miller

genetlink: reorg struct genl_family

2020-10-03T02:11:11+00:00

There are holes and oversized members in struct genl_family. Before: /* size: 104, cachelines: 2, members: 16 */ After: /* size: 88, cachelines: 2, members: 16 */ The command field in struct genlmsghdr is a u8, so no point in the operation count being 32 bit. Also operation 0 is usually undefined, so we only need 255 entries. netnsok and parallel_ops are only ever initialized to true. We can grow the fields as needed, compiler should warn us if someone tries to assign larger constants. Signed-off-by: Jakub Kicinski Reviewed-by: Johannes Berg Signed-off-by: David S. Miller

genetlink: add missing kdoc for validation flags

2020-09-29T01:51:50+00:00

Validation flags are missing kdoc, add it. Fixes: ef6243acb478 ("genetlink: optionally validate strictly/dumps") Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

genetlink: Remove unused function genl_err_attr()

2020-09-17T23:28:13+00:00

It is never used, so can remove it. Signed-off-by: YueHaibing Signed-off-by: David S. Miller

genetlink: remove genl_bind

2020-07-01T22:49:11+00:00

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 Acked-by: Johannes Berg Reported-by: kernel test robot Signed-off-by: Sean Tranchetti Signed-off-by: David S. Miller

genetlink: get rid of family->attrbuf

2020-06-30T00:15:57+00:00

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 Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net: genetlink: remove unused genl_family_attrbuf()

2019-10-06T13:44:47+00:00

genl_family_attrbuf() function is no longer used by anyone, so remove it. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller