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7 daysMerge tag 'nf-26-03-26' of ↵ipvs/mainipvs/HEADPaolo Abeni
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter for net This is v3, I kept back an ipset fix and another to tigthen the xtables interface to reject invalid combinations with the NFPROTO_ARP family. They need a bit more discussion. I fixed the issues reported by AI on patch 9 (add #ifdef to access ct zone, update nf_conntrack_broadcast and patch 10 (use better Fixes: tag). Thanks! The following patchset contains Netfilter fixes for *net*. Note that most bugs fixed here stem from 2.6 days, the large PR is not due to an increase in regressions. 1) Fix incorrect reject of set updates with nf_tables pipapo set avx2 backend. This comes with a regression test in patch 2. From Florian Westphal. 2) nfnetlink_log needs to zero padding to prevent infoleak to userspace, from Weiming Shi. 3) xtables ip6t_rt module never validated that addrnr length is within the allowed array boundary. Reject bogus values. From Ren Wei. 4) Fix high memory usage in rbtree set backend that was unwanted side-effect of the recently added binary search blob. From Pablo Neira Ayuso. 5) Patches 5 to 10, also from Pablo, address long-standing RCU safety bugs in conntracks handling of expectations: We can never safely defer a conntrack extension area without holding a reference. Yet expectation handling does so in multiple places. Fix this by avoiding the need to look into the master conntrack to begin with and by extending locked sections in a few places. 11) Fix use of uninitialized rtp_addr in the sip conntrack helper, also from Weiming Shi. 12) Add stricter netlink policy checks in ctnetlink, from David Carlier. This avoids undefined behaviour when userspace provides huge wscale value. netfilter pull request 26-03-26 * tag 'nf-26-03-26' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: ctnetlink: use netlink policy range checks netfilter: nf_conntrack_sip: fix use of uninitialized rtp_addr in process_sdp netfilter: nf_conntrack_expect: skip expectations in other netns via proc netfilter: nf_conntrack_expect: store netns and zone in expectation netfilter: ctnetlink: ensure safe access to master conntrack netfilter: nf_conntrack_expect: use expect->helper netfilter: nf_conntrack_expect: honor expectation helper field netfilter: nft_set_rbtree: revisit array resize logic netfilter: ip6t_rt: reject oversized addrnr in rt_mt6_check() netfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD selftests: netfilter: nft_concat_range.sh: add check for flush+reload bug netfilter: nft_set_pipapo_avx2: don't return non-matching entry on expiry ==================== Link: https://patch.msgid.link/20260326125153.685915-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
7 daysMerge tag 'for-net-2026-03-25' of ↵Paolo Abeni
git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth Luiz Augusto von Dentz says: ==================== bluetooth pull request for net: - L2CAP: Fix deadlock in l2cap_conn_del() - L2CAP: Fix ERTM re-init and zero pdu_len infinite loop - L2CAP: Fix send LE flow credits in ACL link - btintel: serialize btintel_hw_error() with hci_req_sync_lock - btusb: clamp SCO altsetting table indices * tag 'for-net-2026-03-25' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth: Bluetooth: btusb: clamp SCO altsetting table indices Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop Bluetooth: L2CAP: Fix deadlock in l2cap_conn_del() Bluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock Bluetooth: L2CAP: Fix send LE flow credits in ACL link ==================== Link: https://patch.msgid.link/20260325194358.618892-1-luiz.dentz@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
7 daysnetfilter: ctnetlink: use netlink policy range checksDavid Carlier
Replace manual range and mask validations with netlink policy annotations in ctnetlink code paths, so that the netlink core rejects invalid values early and can generate extack errors. - CTA_PROTOINFO_TCP_STATE: reject values > TCP_CONNTRACK_SYN_SENT2 at policy level, removing the manual >= TCP_CONNTRACK_MAX check. - CTA_PROTOINFO_TCP_WSCALE_ORIGINAL/REPLY: reject values > TCP_MAX_WSCALE (14). The normal TCP option parsing path already clamps to this value, but the ctnetlink path accepted 0-255, causing undefined behavior when used as a u32 shift count. - CTA_FILTER_ORIG_FLAGS/REPLY_FLAGS: use NLA_POLICY_MASK with CTA_FILTER_F_ALL, removing the manual mask checks. - CTA_EXPECT_FLAGS: use NLA_POLICY_MASK with NF_CT_EXPECT_MASK, adding a new mask define grouping all valid expect flags. Extracted from a broader nf-next patch by Florian Westphal, scoped to ctnetlink for the fixes tree. Fixes: c8e2078cfe41 ("[NETFILTER]: ctnetlink: add support for internal tcp connection tracking flags handling") Signed-off-by: David Carlier <devnexen@gmail.com> Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nf_conntrack_sip: fix use of uninitialized rtp_addr in process_sdpWeiming Shi
process_sdp() declares union nf_inet_addr rtp_addr on the stack and passes it to the nf_nat_sip sdp_session hook after walking the SDP media descriptions. However rtp_addr is only initialized inside the media loop when a recognized media type with a non-zero port is found. If the SDP body contains no m= lines, only inactive media sections (m=audio 0 ...) or only unrecognized media types, rtp_addr is never assigned. Despite that, the function still calls hooks->sdp_session() with &rtp_addr, causing nf_nat_sdp_session() to format the stale stack value as an IP address and rewrite the SDP session owner and connection lines with it. With CONFIG_INIT_STACK_ALL_ZERO (default on most distributions) this results in the session-level o= and c= addresses being rewritten to 0.0.0.0 for inactive SDP sessions. Without stack auto-init the rewritten address is whatever happened to be on the stack. Fix this by pre-initializing rtp_addr from the session-level connection address (caddr) when available, and tracking via a have_rtp_addr flag whether any valid address was established. Skip the sdp_session hook entirely when no valid address exists. Fixes: 4ab9e64e5e3c ("[NETFILTER]: nf_nat_sip: split up SDP mangling") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nf_conntrack_expect: skip expectations in other netns via procPablo Neira Ayuso
Skip expectations that do not reside in this netns. Similar to e77e6ff502ea ("netfilter: conntrack: do not dump other netns's conntrack entries via proc"). Fixes: 9b03f38d0487 ("netfilter: netns nf_conntrack: per-netns expectations") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nf_conntrack_expect: store netns and zone in expectationPablo Neira Ayuso
__nf_ct_expect_find() and nf_ct_expect_find_get() are called under rcu_read_lock() but they dereference the master conntrack via exp->master. Since the expectation does not hold a reference on the master conntrack, this could be dying conntrack or different recycled conntrack than the real master due to SLAB_TYPESAFE_RCU. Store the netns, the master_tuple and the zone in struct nf_conntrack_expect as a safety measure. This patch is required by the follow up fix not to dump expectations that do not belong to this netns. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: ctnetlink: ensure safe access to master conntrackPablo Neira Ayuso
Holding reference on the expectation is not sufficient, the master conntrack object can just go away, making exp->master invalid. To access exp->master safely: - Grab the nf_conntrack_expect_lock, this gets serialized with clean_from_lists() which also holds this lock when the master conntrack goes away. - Hold reference on master conntrack via nf_conntrack_find_get(). Not so easy since the master tuple to look up for the master conntrack is not available in the existing problematic paths. This patch goes for extending the nf_conntrack_expect_lock section to address this issue for simplicity, in the cases that are described below this is just slightly extending the lock section. The add expectation command already holds a reference to the master conntrack from ctnetlink_create_expect(). However, the delete expectation command needs to grab the spinlock before looking up for the expectation. Expand the existing spinlock section to address this to cover the expectation lookup. Note that, the nf_ct_expect_iterate_net() calls already grabs the spinlock while iterating over the expectation table, which is correct. The get expectation command needs to grab the spinlock to ensure master conntrack does not go away. This also expands the existing spinlock section to cover the expectation lookup too. I needed to move the netlink skb allocation out of the spinlock to keep it GFP_KERNEL. For the expectation events, the IPEXP_DESTROY event is already delivered under the spinlock, just move the delivery of IPEXP_NEW under the spinlock too because the master conntrack event cache is reached through exp->master. While at it, add lockdep notations to help identify what codepaths need to grab the spinlock. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nf_conntrack_expect: use expect->helperPablo Neira Ayuso
Use expect->helper in ctnetlink and /proc to dump the helper name. Using nfct_help() without holding a reference to the master conntrack is unsafe. Use exp->master->helper in ctnetlink path if userspace does not provide an explicit helper when creating an expectation to retain the existing behaviour. The ctnetlink expectation path holds the reference on the master conntrack and nf_conntrack_expect lock and the nfnetlink glue path refers to the master ct that is attached to the skb. Reported-by: Hyunwoo Kim <imv4bel@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nf_conntrack_expect: honor expectation helper fieldPablo Neira Ayuso
The expectation helper field is mostly unused. As a result, the netfilter codebase relies on accessing the helper through exp->master. Always set on the expectation helper field so it can be used to reach the helper. nf_ct_expect_init() is called from packet path where the skb owns the ct object, therefore accessing exp->master for the newly created expectation is safe. This saves a lot of updates in all callsites to pass the ct object as parameter to nf_ct_expect_init(). This is a preparation patches for follow up fixes. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nft_set_rbtree: revisit array resize logicPablo Neira Ayuso
Chris Arges reports high memory consumption with thousands of containers, this patch revisits the array allocation logic. For anonymous sets, start by 16 slots (which takes 256 bytes on x86_64). Expand it by x2 until threshold of 512 slots is reached, over that threshold, expand it by x1.5. For non-anonymous set, start by 1024 slots in the array (which takes 16 Kbytes initially on x86_64). Expand it by x1.5. Use set->ndeact to subtract deactivated elements when calculating the number of the slots in the array, otherwise the array size array gets increased artifically. Add special case shrink logic to deal with flush set too. The shrink logic is skipped by anonymous sets. Use check_add_overflow() to calculate the new array size. Add a WARN_ON_ONCE check to make sure elements fit into the new array size. Reported-by: Chris Arges <carges@cloudflare.com> Fixes: 7e43e0a1141d ("netfilter: nft_set_rbtree: translate rbtree to array for binary search") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: ip6t_rt: reject oversized addrnr in rt_mt6_check()Ren Wei
Reject rt match rules whose addrnr exceeds IP6T_RT_HOPS. rt_mt6() expects addrnr to stay within the bounds of rtinfo->addrs[]. Validate addrnr during rule installation so malformed rules are rejected before the match logic can use an out-of-range value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Co-developed-by: Yuan Tan <yuantan098@gmail.com> Signed-off-by: Yuan Tan <yuantan098@gmail.com> Suggested-by: Xin Liu <bird@lzu.edu.cn> Tested-by: Yuhang Zheng <z1652074432@gmail.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daysnetfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOADWeiming Shi
__build_packet_message() manually constructs the NFULA_PAYLOAD netlink attribute using skb_put() and skb_copy_bits(), bypassing the standard nla_reserve()/nla_put() helpers. While nla_total_size(data_len) bytes are allocated (including NLA alignment padding), only data_len bytes of actual packet data are copied. The trailing nla_padlen(data_len) bytes (1-3 when data_len is not 4-byte aligned) are never initialized, leaking stale heap contents to userspace via the NFLOG netlink socket. Replace the manual attribute construction with nla_reserve(), which handles the tailroom check, header setup, and padding zeroing via __nla_reserve(). The subsequent skb_copy_bits() fills in the payload data on top of the properly initialized attribute. Fixes: df6fb868d611 ("[NETFILTER]: nfnetlink: convert to generic netlink attribute functions") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
7 daystls: Purge async_hold in tls_decrypt_async_wait()Chuck Lever
The async_hold queue pins encrypted input skbs while the AEAD engine references their scatterlist data. Once tls_decrypt_async_wait() returns, every AEAD operation has completed and the engine no longer references those skbs, so they can be freed unconditionally. A subsequent patch adds batch async decryption to tls_sw_read_sock(), introducing a new call site that must drain pending AEAD operations and release held skbs. Move __skb_queue_purge(&ctx->async_hold) into tls_decrypt_async_wait() so the purge is centralized and every caller -- recvmsg's drain path, the -EBUSY fallback in tls_do_decryption(), and the new read_sock batch path -- releases held skbs on synchronization without each site managing the purge independently. This fixes a leak when tls_strp_msg_hold() fails part-way through, after having added some cloned skbs to the async_hold queue. tls_decrypt_sg() will then call tls_decrypt_async_wait() to process all pending decrypts, and drop back to synchronous mode, but tls_sw_recvmsg() only flushes the async_hold queue when one record has been processed in "fully-async" mode, which may not be the case here. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reported-by: Yiming Qian <yimingqian591@gmail.com> Fixes: b8a6ff84abbc ("tls: wait for pending async decryptions if tls_strp_msg_hold fails") Link: https://patch.msgid.link/20260324-tls-read-sock-v5-1-5408befe5774@oracle.com [pabeni@redhat.com: added leak comment] Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8 daysnetfilter: nft_set_pipapo_avx2: don't return non-matching entry on expiryFlorian Westphal
New test case fails unexpectedly when avx2 matching functions are used. The test first loads a ranomly generated pipapo set with 'ipv4 . port' key, i.e. nft -f foo. This works. Then, it reloads the set after a flush: (echo flush set t s; cat foo) | nft -f - This is expected to work, because its the same set after all and it was already loaded once. But with avx2, this fails: nft reports a clashing element. The reported clash is of following form: We successfully re-inserted a . b c . d Then we try to insert a . d avx2 finds the already existing a . d, which (due to 'flush set') is marked as invalid in the new generation. It skips the element and moves to next. Due to incorrect masking, the skip-step finds the next matching element *only considering the first field*, i.e. we return the already reinserted "a . b", even though the last field is different and the entry should not have been matched. No such error is reported for the generic c implementation (no avx2) or when the last field has to use the 'nft_pipapo_avx2_lookup_slow' fallback. Bisection points to 7711f4bb4b36 ("netfilter: nft_set_pipapo: fix range overlap detection") but that fix merely uncovers this bug. Before this commit, the wrong element is returned, but erronously reported as a full, identical duplicate. The root-cause is too early return in the avx2 match functions. When we process the last field, we should continue to process data until the entire input size has been consumed to make sure no stale bits remain in the map. Link: https://lore.kernel.org/netfilter-devel/20260321152506.037f68c0@elisabeth/ Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysBluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loopHyunwoo Kim
l2cap_config_req() processes CONFIG_REQ for channels in BT_CONNECTED state to support L2CAP reconfiguration (e.g. MTU changes). However, since both CONF_INPUT_DONE and CONF_OUTPUT_DONE are already set from the initial configuration, the reconfiguration path falls through to l2cap_ertm_init(), which re-initializes tx_q, srej_q, srej_list, and retrans_list without freeing the previous allocations and sets chan->sdu to NULL without freeing the existing skb. This leaks all previously allocated ERTM resources. Additionally, l2cap_parse_conf_req() does not validate the minimum value of remote_mps derived from the RFC max_pdu_size option. A zero value propagates to l2cap_segment_sdu() where pdu_len becomes zero, causing the while loop to never terminate since len is never decremented, exhausting all available memory. Fix the double-init by skipping l2cap_ertm_init() and l2cap_chan_ready() when the channel is already in BT_CONNECTED state, while still allowing the reconfiguration parameters to be updated through l2cap_parse_conf_req(). Also add a pdu_len zero check in l2cap_segment_sdu() as a safeguard. Fixes: 96298f640104 ("Bluetooth: L2CAP: handle l2cap config request during open state") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
8 daysBluetooth: L2CAP: Fix deadlock in l2cap_conn_del()Hyunwoo Kim
l2cap_conn_del() calls cancel_delayed_work_sync() for both info_timer and id_addr_timer while holding conn->lock. However, the work functions l2cap_info_timeout() and l2cap_conn_update_id_addr() both acquire conn->lock, creating a potential AB-BA deadlock if the work is already executing when l2cap_conn_del() takes the lock. Move the work cancellations before acquiring conn->lock and use disable_delayed_work_sync() to additionally prevent the works from being rearmed after cancellation, consistent with the pattern used in hci_conn_del(). Fixes: ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
8 daysBluetooth: L2CAP: Fix send LE flow credits in ACL linkZhang Chen
When the L2CAP channel mode is L2CAP_MODE_ERTM/L2CAP_MODE_STREAMING, l2cap_publish_rx_avail will be called and le flow credits will be sent in l2cap_chan_rx_avail, even though the link type is ACL. The logs in question as follows: > ACL Data RX: Handle 129 flags 0x02 dlen 12 L2CAP: Unknown (0x16) ident 4 len 4 40 00 ed 05 < ACL Data TX: Handle 129 flags 0x00 dlen 10 L2CAP: Command Reject (0x01) ident 4 len 2 Reason: Command not understood (0x0000) Bluetooth: Unknown BR/EDR signaling command 0x16 Bluetooth: Wrong link type (-22) Fixes: ce60b9231b66 ("Bluetooth: compute LE flow credits based on recvbuf space") Signed-off-by: Zhang Chen <zhangchen01@kylinos.cn> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
8 daysrtnetlink: fix leak of SRCU struct in rtnl_link_registerSabrina Dubroca
Commit 6b57ff21a310 ("rtnetlink: Protect link_ops by mutex.") swapped the EEXIST check with the init_srcu_struct, but didn't add cleanup of the SRCU struct we just allocated in case of error. Fixes: 6b57ff21a310 ("rtnetlink: Protect link_ops by mutex.") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/e77fe499f9a58c547b33b5212b3596dad417cec6.1774025341.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
9 daysMerge tag 'ipsec-2026-03-23' of ↵Paolo Abeni
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2026-03-23 1) Add missing extack for XFRMA_SA_PCPU in add_acquire and allocspi. From Sabrina Dubroca. 2) Fix the condition on x->pcpu_num in xfrm_sa_len by using the proper check. From Sabrina Dubroca. 3) Call xdo_dev_state_delete during state update to properly cleanup the xdo device state. From Sabrina Dubroca. 4) Fix a potential skb leak in espintcp when async crypto is used. From Sabrina Dubroca. 5) Validate inner IPv4 header length in IPTFS payload to avoid parsing malformed packets. From Roshan Kumar. 6) Fix skb_put() panic on non-linear skb during IPTFS reassembly. From Fernando Fernandez Mancera. 7) Silence various sparse warnings related to RCU, state, and policy handling. From Sabrina Dubroca. 8) Fix work re-schedule race after cancel in xfrm_nat_keepalive_net_fini(). From Hyunwoo Kim. 9) Prevent policy_hthresh.work from racing with netns teardown by using a proper cleanup mechanism. From Minwoo Ra. 10) Validate that the family of the source and destination addresses match in pfkey_send_migrate(). From Eric Dumazet. 11) Only publish mode_data after the clone is setup in the IPTFS receive path. This prevents leaving x->mode_data pointing at freed memory on error. From Paul Moses. Please pull or let me know if there are problems. ipsec-2026-03-23 * tag 'ipsec-2026-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec: xfrm: iptfs: only publish mode_data after clone setup af_key: validate families in pfkey_send_migrate() xfrm: prevent policy_hthresh.work from racing with netns teardown xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini() xfrm: avoid RCU warnings around the per-netns netlink socket xfrm: add rcu_access_pointer to silence sparse warning for xfrm_input_afinfo xfrm: policy: silence sparse warning in xfrm_policy_unregister_afinfo xfrm: policy: fix sparse warnings in xfrm_policy_{init,fini} xfrm: state: silence sparse warnings during netns exit xfrm: remove rcu/state_hold from xfrm_state_lookup_spi_proto xfrm: state: add xfrm_state_deref_prot to state_by* walk under lock xfrm: state: fix sparse warnings around XFRM_STATE_INSERT xfrm: state: fix sparse warnings in xfrm_state_init xfrm: state: fix sparse warnings on xfrm_state_hold_rcu xfrm: iptfs: fix skb_put() panic on non-linear skb during reassembly xfrm: iptfs: validate inner IPv4 header length in IPTFS payload esp: fix skb leak with espintcp and async crypto xfrm: call xdo_dev_state_delete during state update xfrm: fix the condition on x->pcpu_num in xfrm_sa_len xfrm: add missing extack for XFRMA_SA_PCPU in add_acquire and allocspi ==================== Link: https://patch.msgid.link/20260323083440.2741292-1-steffen.klassert@secunet.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
9 daysnet: correctly handle tunneled traffic on IPV6_CSUM GSO fallbackWillem de Bruijn
NETIF_F_IPV6_CSUM only advertises support for checksum offload of packets without IPv6 extension headers. Packets with extension headers must fall back onto software checksumming. Since TSO depends on checksum offload, those must revert to GSO. The below commit introduces that fallback. It always checks network header length. For tunneled packets, the inner header length must be checked instead. Extend the check accordingly. A special case is tunneled packets without inner IP protocol. Such as RFC 6951 SCTP in UDP. Those are not standard IPv6 followed by transport header either, so also must revert to the software GSO path. Cc: stable@vger.kernel.org Fixes: 864e3396976e ("net: gso: Forbid IPv6 TSO with extensions on devices with only IPV6_CSUM") Reported-by: Tangxin Xie <xietangxin@yeah.net> Closes: https://lore.kernel.org/netdev/0414e7e2-9a1c-4d7c-a99d-b9039cf68f40@yeah.net/ Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260320190148.2409107-1-willemdebruijn.kernel@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
9 daysMerge tag 'linux-can-fixes-for-7.0-20260323' of ↵Paolo Abeni
git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can Marc Kleine-Budde says: ==================== pull-request: can 2026-03-23 this is a pull request of 5 patches for net/main. The first patch is by me and adds missing error handling to the CAN netlink device configuration code. Wenyuan Li contributes a patch for the mcp251x drier to add missing error handling for power enabling in th open and resume functions. Oliver Hartkopp's patch adds missing atomic access in hot path for the CAN procfs statistics. A series by Ali Norouzi and Oliver Hartkopp fix a can-Out-of-Bounds Heap R/W in the can-gw protocol and a UAF in the CAN isotp protocol. linux-can-fixes-for-7.0-20260323 * tag 'linux-can-fixes-for-7.0-20260323' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can: can: isotp: fix tx.buf use-after-free in isotp_sendmsg() can: gw: fix OOB heap access in cgw_csum_crc8_rel() can: statistics: add missing atomic access in hot path can: mcp251x: add error handling for power enable in open and resume can: netlink: can_changelink(): add missing error handling to call can_ctrlmode_changelink() ==================== Link: https://patch.msgid.link/20260323103224.218099-1-mkl@pengutronix.de Signed-off-by: Paolo Abeni <pabeni@redhat.com>
9 daysudp: Fix wildcard bind conflict check when using hash2Martin KaFai Lau
When binding a udp_sock to a local address and port, UDP uses two hashes (udptable->hash and udptable->hash2) for collision detection. The current code switches to "hash2" when hslot->count > 10. "hash2" is keyed by local address and local port. "hash" is keyed by local port only. The issue can be shown in the following bind sequence (pseudo code): bind(fd1, "[fd00::1]:8888") bind(fd2, "[fd00::2]:8888") bind(fd3, "[fd00::3]:8888") bind(fd4, "[fd00::4]:8888") bind(fd5, "[fd00::5]:8888") bind(fd6, "[fd00::6]:8888") bind(fd7, "[fd00::7]:8888") bind(fd8, "[fd00::8]:8888") bind(fd9, "[fd00::9]:8888") bind(fd10, "[fd00::10]:8888") /* Correctly return -EADDRINUSE because "hash" is used * instead of "hash2". udp_lib_lport_inuse() detects the * conflict. */ bind(fail_fd, "[::]:8888") /* After one more socket is bound to "[fd00::11]:8888", * hslot->count exceeds 10 and "hash2" is used instead. */ bind(fd11, "[fd00::11]:8888") bind(fail_fd, "[::]:8888") /* succeeds unexpectedly */ The same issue applies to the IPv4 wildcard address "0.0.0.0" and the IPv4-mapped wildcard address "::ffff:0.0.0.0". For example, if there are existing sockets bound to "192.168.1.[1-11]:8888", then binding "0.0.0.0:8888" or "[::ffff:0.0.0.0]:8888" can also miss the conflict when hslot->count > 10. TCP inet_csk_get_port() already has the correct check in inet_use_bhash2_on_bind(). Rename it to inet_use_hash2_on_bind() and move it to inet_hashtables.h so udp.c can reuse it in this fix. Fixes: 30fff9231fad ("udp: bind() optimisation") Reported-by: Andrew Onyshchuk <oandrew@meta.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260319181817.1901357-1-martin.lau@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
9 daysnet: fix fanout UAF in packet_release() via NETDEV_UP raceYochai Eisenrich
`packet_release()` has a race window where `NETDEV_UP` can re-register a socket into a fanout group's `arr[]` array. The re-registration is not cleaned up by `fanout_release()`, leaving a dangling pointer in the fanout array. `packet_release()` does NOT zero `po->num` in its `bind_lock` section. After releasing `bind_lock`, `po->num` is still non-zero and `po->ifindex` still matches the bound device. A concurrent `packet_notifier(NETDEV_UP)` that already found the socket in `sklist` can re-register the hook. For fanout sockets, this re-registration calls `__fanout_link(sk, po)` which adds the socket back into `f->arr[]` and increments `f->num_members`, but does NOT increment `f->sk_ref`. The fix sets `po->num` to zero in `packet_release` while `bind_lock` is held to prevent NETDEV_UP from linking, preventing the race window. This bug was found following an additional audit with Claude Code based on CVE-2025-38617. Fixes: ce06b03e60fc ("packet: Add helpers to register/unregister ->prot_hook") Link: https://blog.calif.io/p/a-race-within-a-race-exploiting-cve Signed-off-by: Yochai Eisenrich <echelonh@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260319200610.25101-1-echelonh@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
9 daysipv6: Don't remove permanent routes with exceptions from tb6_gc_hlist.Kuniyuki Iwashima
The cited commit mechanically put fib6_remove_gc_list() just after every fib6_clean_expires() call. When a temporary route is promoted to a permanent route, there may already be exception routes tied to it. If fib6_remove_gc_list() removes the route from tb6_gc_hlist, such exception routes will no longer be aged. Let's replace fib6_remove_gc_list() with a new helper fib6_may_remove_gc_list() and use fib6_age_exceptions() there. Note that net->ipv6 is only compiled when CONFIG_IPV6 is enabled, so fib6_{add,remove,may_remove}_gc_list() are guarded. Fixes: 5eb902b8e719 ("net/ipv6: Remove expired routes with a separated list of routes.") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20260320072317.2561779-3-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
9 daysipv6: Remove permanent routes from tb6_gc_hlist when all exceptions expire.Kuniyuki Iwashima
Commit 5eb902b8e719 ("net/ipv6: Remove expired routes with a separated list of routes.") introduced a per-table GC list and changed GC to iterate over that list instead of traversing the entire route table. However, it forgot to add permanent routes to tb6_gc_hlist when exception routes are added. Commit cfe82469a00f ("ipv6: add exception routes to GC list in rt6_insert_exception") fixed that issue but introduced another one. Even after all exception routes expire, the permanent routes remain in tb6_gc_hlist, potentially negating the performance benefits intended by the initial change. Let's count gc_args->more before and after rt6_age_exceptions() and remove the permanent route when the delta is 0. Note that the next patch will reuse fib6_age_exceptions(). Fixes: cfe82469a00f ("ipv6: add exception routes to GC list in rt6_insert_exception") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20260320072317.2561779-2-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
12 daysrtnetlink: count IFLA_INFO_SLAVE_KIND in if_nlmsg_sizeSabrina Dubroca
rtnl_link_get_slave_info_data_size counts IFLA_INFO_SLAVE_DATA, but rtnl_link_slave_info_fill adds both IFLA_INFO_SLAVE_DATA and IFLA_INFO_SLAVE_KIND. Fixes: ba7d49b1f0f8 ("rtnetlink: provide api for getting and setting slave info") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://patch.msgid.link/049843b532e23cde7ddba263c0bbe35ba6f0d26d.1773919462.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
12 daysrtnetlink: count IFLA_PARENT_DEV_{NAME,BUS_NAME} in if_nlmsg_sizeSabrina Dubroca
Commit 00e77ed8e64d ("rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME") added those attributes to rtnl_fill_ifinfo, but forgot to extend if_nlmsg_size. Fixes: 00e77ed8e64d ("rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://patch.msgid.link/0b849da95562af45487080528d60f578636aba5c.1773919462.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
12 daysnet/smc: fix double-free of smc_spd_priv when tee() duplicates splice pipe ↵Qi Tang
buffer smc_rx_splice() allocates one smc_spd_priv per pipe_buffer and stores the pointer in pipe_buffer.private. The pipe_buf_operations for these buffers used .get = generic_pipe_buf_get, which only increments the page reference count when tee(2) duplicates a pipe buffer. The smc_spd_priv pointer itself was not handled, so after tee() both the original and the cloned pipe_buffer share the same smc_spd_priv *. When both pipes are subsequently released, smc_rx_pipe_buf_release() is called twice against the same object: 1st call: kfree(priv) sock_put(sk) smc_rx_update_cons() [correct] 2nd call: kfree(priv) sock_put(sk) smc_rx_update_cons() [UAF] KASAN reports a slab-use-after-free in smc_rx_pipe_buf_release(), which then escalates to a NULL-pointer dereference and kernel panic via smc_rx_update_consumer() when it chases the freed priv->smc pointer: BUG: KASAN: slab-use-after-free in smc_rx_pipe_buf_release+0x78/0x2a0 Read of size 8 at addr ffff888004a45740 by task smc_splice_tee_/74 Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xce/0x650 kasan_report+0xc6/0x100 smc_rx_pipe_buf_release+0x78/0x2a0 free_pipe_info+0xd4/0x130 pipe_release+0x142/0x160 __fput+0x1c6/0x490 __x64_sys_close+0x4f/0x90 do_syscall_64+0xa6/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> BUG: kernel NULL pointer dereference, address: 0000000000000020 RIP: 0010:smc_rx_update_consumer+0x8d/0x350 Call Trace: <TASK> smc_rx_pipe_buf_release+0x121/0x2a0 free_pipe_info+0xd4/0x130 pipe_release+0x142/0x160 __fput+0x1c6/0x490 __x64_sys_close+0x4f/0x90 do_syscall_64+0xa6/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Kernel panic - not syncing: Fatal exception Beyond the memory-safety problem, duplicating an SMC splice buffer is semantically questionable: smc_rx_update_cons() would advance the consumer cursor twice for the same data, corrupting receive-window accounting. A refcount on smc_spd_priv could fix the double-free, but the cursor-accounting issue would still need to be addressed separately. The .get callback is invoked by both tee(2) and splice_pipe_to_pipe() for partial transfers; both will now return -EFAULT. Users who need to duplicate SMC socket data must use a copy-based read path. Fixes: 9014db202cb7 ("smc: add support for splice()") Signed-off-by: Qi Tang <tpluszz77@gmail.com> Link: https://patch.msgid.link/20260318064847.23341-1-tpluszz77@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
12 daysopenvswitch: validate MPLS set/set_masked payload lengthYang Yang
validate_set() accepted OVS_KEY_ATTR_MPLS as variable-sized payload for SET/SET_MASKED actions. In action handling, OVS expects fixed-size MPLS key data (struct ovs_key_mpls). Use the already normalized key_len (masked case included) and reject non-matching MPLS action key sizes. Reject invalid MPLS action payload lengths early. Fixes: fbdcdd78da7c ("Change in Openvswitch to support MPLS label depth of 3 in ingress direction") Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Tested-by: Ao Zhou <n05ec@lzu.edu.cn> Co-developed-by: Yuan Tan <tanyuan98@outlook.com> Signed-off-by: Yuan Tan <tanyuan98@outlook.com> Suggested-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Yang Yang <n05ec@lzu.edu.cn> Reviewed-by: Ilya Maximets <i.maximets@ovn.org> Link: https://patch.msgid.link/20260319080228.3423307-1-n05ec@lzu.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
12 daysopenvswitch: defer tunnel netdev_put to RCU releaseYang Yang
ovs_netdev_tunnel_destroy() may run after NETDEV_UNREGISTER already detached the device. Dropping the netdev reference in destroy can race with concurrent readers that still observe vport->dev. Do not release vport->dev in ovs_netdev_tunnel_destroy(). Instead, let vport_netdev_free() drop the reference from the RCU callback, matching the non-tunnel destroy path and avoiding additional synchronization under RTNL. Fixes: a9020fde67a6 ("openvswitch: Move tunnel destroy function to oppenvswitch module.") Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Tested-by: Ao Zhou <n05ec@lzu.edu.cn> Co-developed-by: Yuan Tan <tanyuan98@outlook.com> Signed-off-by: Yuan Tan <tanyuan98@outlook.com> Suggested-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Yang Yang <n05ec@lzu.edu.cn> Reviewed-by: Ilya Maximets <i.maximets@ovn.org> Link: https://patch.msgid.link/20260319074241.3405262-1-n05ec@lzu.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
13 daysnet: openvswitch: Avoid releasing netdev before teardown completesToke Høiland-Jørgensen
The patch cited in the Fixes tag below changed the teardown code for OVS ports to no longer unconditionally take the RTNL. After this change, the netdev_destroy() callback can proceed immediately to the call_rcu() invocation if the IFF_OVS_DATAPATH flag is already cleared on the netdev. The ovs_netdev_detach_dev() function clears the flag before completing the unregistration, and if it gets preempted after clearing the flag (as can happen on an -rt kernel), netdev_destroy() can complete and the device can be freed before the unregistration completes. This leads to a splat like: [ 998.393867] Oops: general protection fault, probably for non-canonical address 0xff00000001000239: 0000 [#1] SMP PTI [ 998.393877] CPU: 42 UID: 0 PID: 55177 Comm: ip Kdump: loaded Not tainted 6.12.0-211.1.1.el10_2.x86_64+rt #1 PREEMPT_RT [ 998.393886] Hardware name: Dell Inc. PowerEdge R740/0JMK61, BIOS 2.24.0 03/27/2025 [ 998.393889] RIP: 0010:dev_set_promiscuity+0x8d/0xa0 [ 998.393901] Code: 00 00 75 d8 48 8b 53 08 48 83 ba b0 02 00 00 00 75 ca 48 83 c4 08 5b c3 cc cc cc cc 48 83 bf 48 09 00 00 00 75 91 48 8b 47 08 <48> 83 b8 b0 02 00 00 00 74 97 eb 81 0f 1f 80 00 00 00 00 90 90 90 [ 998.393906] RSP: 0018:ffffce5864a5f6a0 EFLAGS: 00010246 [ 998.393912] RAX: ff00000000ffff89 RBX: ffff894d0adf5a05 RCX: 0000000000000000 [ 998.393917] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff894d0adf5a05 [ 998.393921] RBP: ffff894d19252000 R08: ffff894d19252000 R09: 0000000000000000 [ 998.393924] R10: ffff894d19252000 R11: ffff894d192521b8 R12: 0000000000000006 [ 998.393927] R13: ffffce5864a5f738 R14: 00000000ffffffe2 R15: 0000000000000000 [ 998.393931] FS: 00007fad61971800(0000) GS:ffff894cc0140000(0000) knlGS:0000000000000000 [ 998.393936] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 998.393940] CR2: 000055df0a2a6e40 CR3: 000000011c7fe003 CR4: 00000000007726f0 [ 998.393944] PKRU: 55555554 [ 998.393946] Call Trace: [ 998.393949] <TASK> [ 998.393952] ? show_trace_log_lvl+0x1b0/0x2f0 [ 998.393961] ? show_trace_log_lvl+0x1b0/0x2f0 [ 998.393975] ? dp_device_event+0x41/0x80 [openvswitch] [ 998.394009] ? __die_body.cold+0x8/0x12 [ 998.394016] ? die_addr+0x3c/0x60 [ 998.394027] ? exc_general_protection+0x16d/0x390 [ 998.394042] ? asm_exc_general_protection+0x26/0x30 [ 998.394058] ? dev_set_promiscuity+0x8d/0xa0 [ 998.394066] ? ovs_netdev_detach_dev+0x3a/0x80 [openvswitch] [ 998.394092] dp_device_event+0x41/0x80 [openvswitch] [ 998.394102] notifier_call_chain+0x5a/0xd0 [ 998.394106] unregister_netdevice_many_notify+0x51b/0xa60 [ 998.394110] rtnl_dellink+0x169/0x3e0 [ 998.394121] ? rt_mutex_slowlock.constprop.0+0x95/0xd0 [ 998.394125] rtnetlink_rcv_msg+0x142/0x3f0 [ 998.394128] ? avc_has_perm_noaudit+0x69/0xf0 [ 998.394130] ? __pfx_rtnetlink_rcv_msg+0x10/0x10 [ 998.394132] netlink_rcv_skb+0x50/0x100 [ 998.394138] netlink_unicast+0x292/0x3f0 [ 998.394141] netlink_sendmsg+0x21b/0x470 [ 998.394145] ____sys_sendmsg+0x39d/0x3d0 [ 998.394149] ___sys_sendmsg+0x9a/0xe0 [ 998.394156] __sys_sendmsg+0x7a/0xd0 [ 998.394160] do_syscall_64+0x7f/0x170 [ 998.394162] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 998.394165] RIP: 0033:0x7fad61bf4724 [ 998.394188] Code: 89 02 b8 ff ff ff ff eb bb 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 80 3d c5 e9 0c 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 89 54 24 1c 48 89 [ 998.394189] RSP: 002b:00007ffd7e2f7cb8 EFLAGS: 00000202 ORIG_RAX: 000000000000002e [ 998.394191] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fad61bf4724 [ 998.394193] RDX: 0000000000000000 RSI: 00007ffd7e2f7d20 RDI: 0000000000000003 [ 998.394194] RBP: 00007ffd7e2f7d90 R08: 0000000000000010 R09: 000000000000003f [ 998.394195] R10: 000055df11558010 R11: 0000000000000202 R12: 00007ffd7e2f8380 [ 998.394196] R13: 0000000069b233d7 R14: 000055df0a256040 R15: 0000000000000000 [ 998.394200] </TASK> To fix this, reorder the operations in ovs_netdev_detach_dev() to only clear the flag after completing the other operations, and introduce an smp_wmb() to make the ordering requirement explicit. The smp_wmb() is paired with a full smp_mb() in netdev_destroy() to make sure the call_rcu() invocation does not happen before the unregister operations are visible. Reported-by: Minxi Hou <mhou@redhat.com> Tested-by: Minxi Hou <mhou@redhat.com> Fixes: 549822767630 ("net: openvswitch: Avoid needlessly taking the RTNL on vport destroy") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20260318155554.1133405-1-toke@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
13 daysnfc: nci: fix circular locking dependency in nci_close_deviceJakub Kicinski
nci_close_device() flushes rx_wq and tx_wq while holding req_lock. This causes a circular locking dependency because nci_rx_work() running on rx_wq can end up taking req_lock too: nci_rx_work -> nci_rx_data_packet -> nci_data_exchange_complete -> __sk_destruct -> rawsock_destruct -> nfc_deactivate_target -> nci_deactivate_target -> nci_request -> mutex_lock(&ndev->req_lock) Move the flush of rx_wq after req_lock has been released. This should safe (I think) because NCI_UP has already been cleared and the transport is closed, so the work will see it and return -ENETDOWN. NIPA has been hitting this running the nci selftest with a debug kernel on roughly 4% of the runs. Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation") Reviewed-by: Ian Ray <ian.ray@gehealthcare.com> Link: https://patch.msgid.link/20260317193334.988609-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
13 daysMerge tag 'for-net-2026-03-19' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth Luiz Augusto von Dentz says: ==================== bluetooth pull request for net: - hci_ll: Fix firmware leak on error path - hci_sync: annotate data-races around hdev->req_status - L2CAP: Fix null-ptr-deref on l2cap_sock_ready_cb - L2CAP: Validate PDU length before reading SDU length in l2cap_ecred_data_rcv() - L2CAP: Fix regressions caused by reusing ident - L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req - MGMT: Fix dangling pointer on mgmt_add_adv_patterns_monitor_complete - SCO: Fix use-after-free in sco_recv_frame() due to missing sock_hold * tag 'for-net-2026-03-19' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth: Bluetooth: L2CAP: Fix regressions caused by reusing ident Bluetooth: L2CAP: Fix null-ptr-deref on l2cap_sock_ready_cb Bluetooth: hci_ll: Fix firmware leak on error path Bluetooth: hci_sync: annotate data-races around hdev->req_status Bluetooth: MGMT: Fix dangling pointer on mgmt_add_adv_patterns_monitor_complete Bluetooth: SCO: Fix use-after-free in sco_recv_frame() due to missing sock_hold Bluetooth: L2CAP: Validate PDU length before reading SDU length in l2cap_ecred_data_rcv() Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req ==================== Link: https://patch.msgid.link/20260319190455.135302-1-luiz.dentz@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
14 daysBluetooth: L2CAP: Fix regressions caused by reusing identLuiz Augusto von Dentz
This attempt to fix regressions caused by reusing ident which apparently is not handled well on certain stacks causing the stack to not respond to requests, so instead of simple returning the first unallocated id this stores the last used tx_ident and then attempt to use the next until all available ids are exausted and then cycle starting over to 1. Link: https://bugzilla.kernel.org/show_bug.cgi?id=221120 Link: https://bugzilla.kernel.org/show_bug.cgi?id=221177 Fixes: 6c3ea155e5ee ("Bluetooth: L2CAP: Fix not tracking outstanding TX ident") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Tested-by: Christian Eggers <ceggers@arri.de>
14 daysBluetooth: L2CAP: Fix null-ptr-deref on l2cap_sock_ready_cbHelen Koike
Before using sk pointer, check if it is null. Fix the following: KASAN: null-ptr-deref in range [0x0000000000000260-0x0000000000000267] CPU: 0 UID: 0 PID: 5985 Comm: kworker/0:5 Not tainted 7.0.0-rc4-00029-ga989fde763f4 #1 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-9.fc43 06/10/2025 Workqueue: events l2cap_info_timeout RIP: 0010:kasan_byte_accessible+0x12/0x30 Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cce veth0_macvtap: entered promiscuous mode RSP: 0018:ffffc90006e0f808 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffff89746018 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff89746018 RDI: 000000000000004c RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8aae3e70 R12: 0000000000000000 R13: 0000000000000260 R14: 0000000000000260 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880983c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005582615a5008 CR3: 000000007007e000 CR4: 0000000000752ef0 PKRU: 55555554 Call Trace: <TASK> __kasan_check_byte+0x12/0x40 lock_acquire+0x79/0x2e0 lock_sock_nested+0x48/0x100 ? l2cap_sock_ready_cb+0x46/0x160 l2cap_sock_ready_cb+0x46/0x160 l2cap_conn_start+0x779/0xff0 ? __pfx_l2cap_conn_start+0x10/0x10 ? l2cap_info_timeout+0x60/0xa0 ? __pfx___mutex_lock+0x10/0x10 l2cap_info_timeout+0x68/0xa0 ? process_scheduled_works+0xa8d/0x18c0 process_scheduled_works+0xb6e/0x18c0 ? __pfx_process_scheduled_works+0x10/0x10 ? assign_work+0x3d5/0x5e0 worker_thread+0xa53/0xfc0 kthread+0x388/0x470 ? __pfx_worker_thread+0x10/0x10 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x51e/0xb90 ? __pfx_ret_from_fork+0x10/0x10 veth1_macvtap: entered promiscuous mode ? __switch_to+0xc7d/0x1450 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- batman_adv: batadv0: Interface activated: batadv_slave_0 batman_adv: batadv0: Interface activated: batadv_slave_1 netdevsim netdevsim7 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim7 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim7 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim7 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 RIP: 0010:kasan_byte_accessible+0x12/0x30 Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cce ieee80211 phy39: Selected rate control algorithm 'minstrel_ht' RSP: 0018:ffffc90006e0f808 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffff89746018 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff89746018 RDI: 000000000000004c RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8aae3e70 R12: 0000000000000000 R13: 0000000000000260 R14: 0000000000000260 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880983c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7e16139e9c CR3: 000000000e74e000 CR4: 0000000000752ef0 PKRU: 55555554 Kernel panic - not syncing: Fatal exception Fixes: 54a59aa2b562 ("Bluetooth: Add l2cap_chan->ops->ready()") Signed-off-by: Helen Koike <koike@igalia.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
14 daysBluetooth: hci_sync: annotate data-races around hdev->req_statusCen Zhang
__hci_cmd_sync_sk() sets hdev->req_status under hdev->req_lock: hdev->req_status = HCI_REQ_PEND; However, several other functions read or write hdev->req_status without holding any lock: - hci_send_cmd_sync() reads req_status in hci_cmd_work (workqueue) - hci_cmd_sync_complete() reads/writes from HCI event completion - hci_cmd_sync_cancel() / hci_cmd_sync_cancel_sync() read/write - hci_abort_conn() reads in connection abort path Since __hci_cmd_sync_sk() runs on hdev->req_workqueue while hci_send_cmd_sync() runs on hdev->workqueue, these are different workqueues that can execute concurrently on different CPUs. The plain C accesses constitute a data race. Add READ_ONCE()/WRITE_ONCE() annotations on all concurrent accesses to hdev->req_status to prevent potential compiler optimizations that could affect correctness (e.g., load fusing in the wait_event condition or store reordering). Signed-off-by: Cen Zhang <zzzccc427@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
14 daysBluetooth: MGMT: Fix dangling pointer on mgmt_add_adv_patterns_monitor_completeLuiz Augusto von Dentz
This fixes the condition checking so mgmt_pending_valid is executed whenever status != -ECANCELED otherwise calling mgmt_pending_free(cmd) would kfree(cmd) without unlinking it from the list first, leaving a dangling pointer. Any subsequent list traversal (e.g., mgmt_pending_foreach during __mgmt_power_off, or another mgmt_pending_valid call) would dereference freed memory. Link: https://lore.kernel.org/linux-bluetooth/20260315132013.75ab40c5@kernel.org/T/#m1418f9c82eeff8510c1beaa21cf53af20db96c06 Fixes: 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
14 daysBluetooth: SCO: Fix use-after-free in sco_recv_frame() due to missing sock_holdHyunwoo Kim
sco_recv_frame() reads conn->sk under sco_conn_lock() but immediately releases the lock without holding a reference to the socket. A concurrent close() can free the socket between the lock release and the subsequent sk->sk_state access, resulting in a use-after-free. Other functions in the same file (sco_sock_timeout(), sco_conn_del()) correctly use sco_sock_hold() to safely hold a reference under the lock. Fix by using sco_sock_hold() to take a reference before releasing the lock, and adding sock_put() on all exit paths. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
14 daysBluetooth: L2CAP: Validate PDU length before reading SDU length in ↵Hyunwoo Kim
l2cap_ecred_data_rcv() l2cap_ecred_data_rcv() reads the SDU length field from skb->data using get_unaligned_le16() without first verifying that skb contains at least L2CAP_SDULEN_SIZE (2) bytes. When skb->len is less than 2, this reads past the valid data in the skb. The ERTM reassembly path correctly calls pskb_may_pull() before reading the SDU length (l2cap_reassemble_sdu, L2CAP_SAR_START case). Apply the same validation to the Enhanced Credit Based Flow Control data path. Fixes: aac23bf63659 ("Bluetooth: Implement LE L2CAP reassembly") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
14 daysBluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_reqMinseo Park
Syzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd() that is triggered by a malformed Enhanced Credit Based Connection Request. The vulnerability stems from l2cap_ecred_conn_req(). The function allocates a local stack buffer (`pdu`) designed to hold a maximum of 5 Source Channel IDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more than 5 SCIDs, the function calculates `rsp_len` based on this unvalidated `cmd_len` before checking if the number of SCIDs exceeds L2CAP_ECRED_MAX_CID. If the SCID count is too high, the function correctly jumps to the `response` label to reject the packet, but `rsp_len` retains the attacker's oversized value. Consequently, l2cap_send_cmd() is instructed to read past the end of the 18-byte `pdu` buffer, triggering a KASAN panic. Fix this by moving the assignment of `rsp_len` to after the `num_scid` boundary check. If the packet is rejected, `rsp_len` will safely remain 0, and the error response will only read the 8-byte base header from the stack. Fixes: c28d2bff7044 ("Bluetooth: L2CAP: Fix result of L2CAP_ECRED_CONN_RSP when MTU is too short") Reported-by: syzbot+b7f3e7d9a596bf6a63e3@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=b7f3e7d9a596bf6a63e3 Tested-by: syzbot+b7f3e7d9a596bf6a63e3@syzkaller.appspotmail.com Signed-off-by: Minseo Park <jacob.park.9436@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
14 daysMerge tag 'net-7.0-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from wireless, Bluetooth and netfilter. Nothing too exciting here, mostly fixes for corner cases. Current release - fix to a fix: - bonding: prevent potential infinite loop in bond_header_parse() Current release - new code bugs: - wifi: mac80211: check tdls flag in ieee80211_tdls_oper Previous releases - regressions: - af_unix: give up GC if MSG_PEEK intervened - netfilter: conntrack: add missing netlink policy validations - NFC: nxp-nci: allow GPIOs to sleep" * tag 'net-7.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (78 commits) MPTCP: fix lock class name family in pm_nl_create_listen_socket icmp: fix NULL pointer dereference in icmp_tag_validation() net: dsa: bcm_sf2: fix missing clk_disable_unprepare() in error paths net: shaper: protect from late creation of hierarchy net: shaper: protect late read accesses to the hierarchy net: mvpp2: guard flow control update with global_tx_fc in buffer switching nfnetlink_osf: validate individual option lengths in fingerprints netfilter: nf_tables: release flowtable after rcu grace period on error netfilter: bpf: defer hook memory release until rcu readers are done net: bonding: fix NULL deref in bond_debug_rlb_hash_show udp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n net/mlx5e: Fix race condition during IPSec ESN update net/mlx5e: Prevent concurrent access to IPSec ASO context net/mlx5: qos: Restrict RTNL area to avoid a lock cycle ipv6: add NULL checks for idev in SRv6 paths NFC: nxp-nci: allow GPIOs to sleep net: macb: fix uninitialized rx_fs_lock net: macb: fix use-after-free access to PTP clock netdevsim: drop PSP ext ref on forward failure wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure ...
14 daysMPTCP: fix lock class name family in pm_nl_create_listen_socketLi Xiasong
In mptcp_pm_nl_create_listen_socket(), use entry->addr.family instead of sk->sk_family for lock class setup. The 'sk' parameter is a netlink socket, not the MPTCP subflow socket being created. Fixes: cee4034a3db1 ("mptcp: fix lockdep false positive in mptcp_pm_nl_create_listen_socket()") Signed-off-by: Li Xiasong <lixiasong1@huawei.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20260319112159.3118874-1-lixiasong1@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
14 daysicmp: fix NULL pointer dereference in icmp_tag_validation()Weiming Shi
icmp_tag_validation() unconditionally dereferences the result of rcu_dereference(inet_protos[proto]) without checking for NULL. The inet_protos[] array is sparse -- only about 15 of 256 protocol numbers have registered handlers. When ip_no_pmtu_disc is set to 3 (hardened PMTU mode) and the kernel receives an ICMP Fragmentation Needed error with a quoted inner IP header containing an unregistered protocol number, the NULL dereference causes a kernel panic in softirq context. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143) Call Trace: <IRQ> icmp_rcv (net/ipv4/icmp.c:1527) ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207) ip_local_deliver_finish (net/ipv4/ip_input.c:242) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) __netif_receive_skb_one_core (net/core/dev.c:6164) process_backlog (net/core/dev.c:6628) handle_softirqs (kernel/softirq.c:561) </IRQ> Add a NULL check before accessing icmp_strict_tag_validation. If the protocol has no registered handler, return false since it cannot perform strict tag validation. Fixes: 8ed1dc44d3e9 ("ipv4: introduce hardened ip_no_pmtu_disc mode") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Link: https://patch.msgid.link/20260318130558.1050247-4-bestswngs@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
14 dayscan: isotp: fix tx.buf use-after-free in isotp_sendmsg()Oliver Hartkopp
isotp_sendmsg() uses only cmpxchg() on so->tx.state to serialize access to so->tx.buf. isotp_release() waits for ISOTP_IDLE via wait_event_interruptible() and then calls kfree(so->tx.buf). If a signal interrupts the wait_event_interruptible() inside close() while tx.state is ISOTP_SENDING, the loop exits early and release proceeds to force ISOTP_SHUTDOWN and continues to kfree(so->tx.buf) while sendmsg may still be reading so->tx.buf for the final CAN frame in isotp_fill_dataframe(). The so->tx.buf can be allocated once when the standard tx.buf length needs to be extended. Move the kfree() of this potentially extended tx.buf to sk_destruct time when either isotp_sendmsg() and isotp_release() are done. Fixes: 96d1c81e6a04 ("can: isotp: add module parameter for maximum pdu size") Cc: stable@vger.kernel.org Reported-by: Ali Norouzi <ali.norouzi@keysight.com> Co-developed-by: Ali Norouzi <ali.norouzi@keysight.com> Signed-off-by: Ali Norouzi <ali.norouzi@keysight.com> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20260319-fix-can-gw-and-can-isotp-v2-2-c45d52c6d2d8@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
14 dayscan: gw: fix OOB heap access in cgw_csum_crc8_rel()Ali Norouzi
cgw_csum_crc8_rel() correctly computes bounds-safe indices via calc_idx(): int from = calc_idx(crc8->from_idx, cf->len); int to = calc_idx(crc8->to_idx, cf->len); int res = calc_idx(crc8->result_idx, cf->len); if (from < 0 || to < 0 || res < 0) return; However, the loop and the result write then use the raw s8 fields directly instead of the computed variables: for (i = crc8->from_idx; ...) /* BUG: raw negative index */ cf->data[crc8->result_idx] = ...; /* BUG: raw negative index */ With from_idx = to_idx = result_idx = -64 on a 64-byte CAN FD frame, calc_idx(-64, 64) = 0 so the guard passes, but the loop iterates with i = -64, reading cf->data[-64], and the write goes to cf->data[-64]. This write might end up to 56 (7.0-rc) or 40 (<= 6.19) bytes before the start of the canfd_frame on the heap. The companion function cgw_csum_xor_rel() uses `from`/`to`/`res` correctly throughout; fix cgw_csum_crc8_rel() to match. Confirmed with KASAN on linux-7.0-rc2: BUG: KASAN: slab-out-of-bounds in cgw_csum_crc8_rel+0x515/0x5b0 Read of size 1 at addr ffff8880076619c8 by task poc_cgw_oob/62 To configure the can-gw crc8 checksums CAP_NET_ADMIN is needed. Fixes: 456a8a646b25 ("can: gw: add support for CAN FD frames") Cc: stable@vger.kernel.org Reported-by: Ali Norouzi <ali.norouzi@keysight.com> Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Ali Norouzi <ali.norouzi@keysight.com> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20260319-fix-can-gw-and-can-isotp-v2-1-c45d52c6d2d8@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
14 daysMerge tag 'nf-26-03-19' of ↵Paolo Abeni
https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Florian Westphal says: ==================== netfilter: updates for net The following patchset contains Netfilter fixes for *net*: 1) Fix UaF when netfilter bpf link goes away while nfnetlink dumps current hook list, we have to wait until rcu readers are gone. 2) Fix UaF when flowtable fails to register all devices, similar bug as 1). From Pablo Neira Ayuso. 3) nfnetlink_osf fails to properly validate option length fields. From Weiming Shi. netfilter pull request nf-26-03-19 * tag 'nf-26-03-19' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: nfnetlink_osf: validate individual option lengths in fingerprints netfilter: nf_tables: release flowtable after rcu grace period on error netfilter: bpf: defer hook memory release until rcu readers are done ==================== Link: https://patch.msgid.link/20260319093834.19933-1-fw@strlen.de Signed-off-by: Paolo Abeni <pabeni@redhat.com>
14 dayscan: statistics: add missing atomic access in hot pathOliver Hartkopp
Commit 80b5f90158d1 ("can: statistics: use atomic access in hot path") fixed a KCSAN issue in can_receive() but missed to convert the 'matches' variable used in can_rcv_filter(). Fixes: 80b5f90158d1 ("can: statistics: use atomic access in hot path") Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20260318173413.28235-1-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
14 daysnet: shaper: protect from late creation of hierarchyJakub Kicinski
We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. The netdev may get unregistered in between the time we take the ref and the time we lock it. We may allocate the hierarchy after flush has already run, which would lead to a leak. Take the instance lock in pre- already, this saves us from the race and removes the need for dedicated lock/unlock callbacks completely. After all, if there's any chance of write happening concurrently with the flush - we're back to leaking the hierarchy. We may take the lock for devices which don't support shapers but we're only dealing with SET operations here, not taking the lock would be optimizing for an error case. Fixes: 93954b40f6a4 ("net-shapers: implement NL set and delete operations") Link: https://lore.kernel.org/20260309173450.538026-1-p@1g4.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20260317161014.779569-2-kuba@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
14 daysnet: shaper: protect late read accesses to the hierarchyJakub Kicinski
We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. This is not proper, a conversion from a ref to a locked netdev must include a liveness check (a check if the netdev hasn't been unregistered already). Fix the read cases (those under RCU). Writes needs a separate change to protect from creating the hierarchy after flush has already run. Fixes: 4b623f9f0f59 ("net-shapers: implement NL get operation") Reported-by: Paul Moses <p@1g4.org> Link: https://lore.kernel.org/20260309173450.538026-1-p@1g4.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20260317161014.779569-1-kuba@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-03-19nfnetlink_osf: validate individual option lengths in fingerprintsWeiming Shi
nfnl_osf_add_callback() validates opt_num bounds and string NUL-termination but does not check individual option length fields. A zero-length option causes nf_osf_match_one() to enter the option matching loop even when foptsize sums to zero, which matches packets with no TCP options where ctx->optp is NULL: Oops: general protection fault KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: nf_osf_match (net/netfilter/nfnetlink_osf.c:227) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:293) nf_hook_slow (net/netfilter/core.c:623) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) Additionally, an MSS option (kind=2) with length < 4 causes out-of-bounds reads when nf_osf_match_one() unconditionally accesses optp[2] and optp[3] for MSS value extraction. While RFC 9293 section 3.2 specifies that the MSS option is always exactly 4 bytes (Kind=2, Length=4), the check uses "< 4" rather than "!= 4" because lengths greater than 4 do not cause memory safety issues -- the buffer is guaranteed to be at least foptsize bytes by the ctx->optsize == foptsize check. Reject fingerprints where any option has zero length, or where an MSS option has length less than 4, at add time rather than trusting these values in the packet matching hot path. Fixes: 11eeef41d5f6 ("netfilter: passive OS fingerprint xtables match") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de>