linux/net/netfilter/nfnetlink_queue.c, branch v6.17

netfilter: nfnetlink_queue: Initialize ctx to avoid memory allocation error

2025-03-23T09:20:33Z

It is possible that ctx in nfqnl_build_packet_message() could be used before it is properly initialize, which is only initialized by nfqnl_get_sk_secctx(). This patch corrects this problem by initializing the lsmctx to a safe value when it is declared. This is similar to the commit 35fcac7a7c25 ("audit: Initialize lsmctx to avoid memory allocation error"). Fixes: 2d470c778120 ("lsm: replace context+len with lsm_context") Signed-off-by: Chenyuan Yang Signed-off-by: Pablo Neira Ayuso

net: corrections for security_secid_to_secctx returns

2025-01-05T03:11:22Z

security_secid_to_secctx() returns the size of the new context, whereas previous versions provided that via a pointer parameter. Correct the type of the value returned in nfqnl_get_sk_secctx() and the check for error in netlbl_unlhsh_add(). Add an error check. Fixes: 2d470c778120 ("lsm: replace context+len with lsm_context") Signed-off-by: Casey Schaufler Signed-off-by: Paul Moore

lsm: replace context+len with lsm_context

2024-12-04T19:42:31Z

Replace the (secctx,seclen) pointer pair with a single lsm_context pointer to allow return of the LSM identifier along with the context and context length. This allows security_release_secctx() to know how to release the context. Callers have been modified to use or save the returned data from the new structure. security_secid_to_secctx() and security_lsmproc_to_secctx() will now return the length value on success instead of 0. Cc: netdev@vger.kernel.org Cc: audit@vger.kernel.org Cc: netfilter-devel@vger.kernel.org Cc: Todd Kjos Signed-off-by: Casey Schaufler [PM: subject tweak, kdoc fix, signedness fix from Dan Carpenter] Signed-off-by: Paul Moore

lsm: ensure the correct LSM context releaser

2024-12-04T15:46:26Z

Add a new lsm_context data structure to hold all the information about a "security context", including the string, its size and which LSM allocated the string. The allocation information is necessary because LSMs have different policies regarding the lifecycle of these strings. SELinux allocates and destroys them on each use, whereas Smack provides a pointer to an entry in a list that never goes away. Update security_release_secctx() to use the lsm_context instead of a (char *, len) pair. Change its callers to do likewise. The LSMs supporting this hook have had comments added to remind the developer that there is more work to be done. The BPF security module provides all LSM hooks. While there has yet to be a known instance of a BPF configuration that uses security contexts, the possibility is real. In the existing implementation there is potential for multiple frees in that case. Cc: linux-integrity@vger.kernel.org Cc: netdev@vger.kernel.org Cc: audit@vger.kernel.org Cc: netfilter-devel@vger.kernel.org To: Pablo Neira Ayuso Cc: linux-nfs@vger.kernel.org Cc: Todd Kjos Signed-off-by: Casey Schaufler [PM: subject tweak] Signed-off-by: Paul Moore

netfilter: nfnetlink_queue: unbreak SCTP traffic

2024-08-19T16:44:50Z

when packet is enqueued with nfqueue and GSO is enabled, checksum calculation has to take into account the protocol, as SCTP uses a 32 bits CRC checksum. Enter skb_gso_segment() path in case of SCTP GSO packets because skb_zerocopy() does not support for GSO_BY_FRAGS. Joint work with Pablo. Signed-off-by: Antonio Ojea Signed-off-by: Pablo Neira Ayuso

netfilter: nf_queue: drop packets with cloned unconfirmed conntracks

2024-08-14T21:37:23Z

Conntrack assumes an unconfirmed entry (not yet committed to global hash table) has a refcount of 1 and is not visible to other cores. With multicast forwarding this assumption breaks down because such skbs get cloned after being picked up, i.e. ct->use refcount is > 1. Likewise, bridge netfilter will clone broad/mutlicast frames and all frames in case they need to be flood-forwarded during learning phase. For ip multicast forwarding or plain bridge flood-forward this will "work" because packets don't leave softirq and are implicitly serialized. With nfqueue this no longer holds true, the packets get queued and can be reinjected in arbitrary ways. Disable this feature, I see no other solution. After this patch, nfqueue cannot queue packets except the last multicast/broadcast packet. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink_queue: drop bogus WARN_ON

2024-07-11T09:26:33Z

Happens when rules get flushed/deleted while packet is out, so remove this WARN_ON. This WARN exists in one form or another since v4.14, no need to backport this to older releases, hence use a more recent fixes tag. Fixes: 3f8019688894 ("netfilter: move nf_reinject into nfnetlink_queue modules") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202407081453.11ac0f63-lkp@intel.com Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu()

2024-05-20T09:38:42Z

syzbot reported that nf_reinject() could be called without rcu_read_lock() : WARNING: suspicious RCU usage 6.9.0-rc7-syzkaller-02060-g5c1672705a1a #0 Not tainted net/netfilter/nfnetlink_queue.c:263 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by syz-executor.4/13427: #0: ffffffff8e334f60 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334f60 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2190 [inline] #0: ffffffff8e334f60 (rcu_callback){....}-{0:0}, at: rcu_core+0xa86/0x1830 kernel/rcu/tree.c:2471 #1: ffff88801ca92958 (&inst->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff88801ca92958 (&inst->lock){+.-.}-{2:2}, at: nfqnl_flush net/netfilter/nfnetlink_queue.c:405 [inline] #1: ffff88801ca92958 (&inst->lock){+.-.}-{2:2}, at: instance_destroy_rcu+0x30/0x220 net/netfilter/nfnetlink_queue.c:172 stack backtrace: CPU: 0 PID: 13427 Comm: syz-executor.4 Not tainted 6.9.0-rc7-syzkaller-02060-g5c1672705a1a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712 nf_reinject net/netfilter/nfnetlink_queue.c:323 [inline] nfqnl_reinject+0x6ec/0x1120 net/netfilter/nfnetlink_queue.c:397 nfqnl_flush net/netfilter/nfnetlink_queue.c:410 [inline] instance_destroy_rcu+0x1ae/0x220 net/netfilter/nfnetlink_queue.c:172 rcu_do_batch kernel/rcu/tree.c:2196 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471 handle_softirqs+0x2d6/0x990 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 Fixes: 9872bec773c2 ("[NETFILTER]: nfnetlink: use RCU for queue instances hash") Reported-by: syzbot Signed-off-by: Eric Dumazet Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: move nf_reinject into nfnetlink_queue modules

2024-02-21T11:03:22Z

No need to keep this in the core, move it to the nfnetlink_queue module. nf_reroute is moved too, there were no other callers. Signed-off-by: Florian Westphal

netfilter: nfnetlink_queue: un-break NF_REPEAT

2024-02-08T11:10:19Z

Only override userspace verdict if the ct hook returns something other than ACCEPT. Else, this replaces NF_REPEAT (run all hooks again) with NF_ACCEPT (move to next hook). Fixes: 6291b3a67ad5 ("netfilter: conntrack: convert nf_conntrack_update to netfilter verdicts") Reported-by: l.6diay@passmail.com Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso