kernel/linux.git/include/linux/skbuff.h, branch v5.10.258

netmem: fix skb_frag_address_safe with unreadable skbs

2025-08-28T14:22:43+00:00

[ Upstream commit 4672aec56d2e8edabcb74c3e2320301d106a377e ] skb_frag_address_safe() needs a check that the skb_frag_page exists check similar to skb_frag_address(). Cc: ap420073@gmail.com Signed-off-by: Mina Almasry Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20250619175239.3039329-1-almasrymina@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv6: reject malicious packets in ipv6_gso_segment()

2025-08-28T14:22:37+00:00

[ Upstream commit d45cf1e7d7180256e17c9ce88e32e8061a7887fe ] syzbot was able to craft a packet with very long IPv6 extension headers leading to an overflow of skb->transport_header. This 16bit field has a limited range. Add skb_reset_transport_header_careful() helper and use it from ipv6_gso_segment() WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 skb_reset_transport_header include/linux/skbuff.h:3032 [inline] WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151 Modules linked in: CPU: 0 UID: 0 PID: 5871 Comm: syz-executor211 Not tainted 6.16.0-rc6-syzkaller-g7abc678e3084 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:skb_reset_transport_header include/linux/skbuff.h:3032 [inline] RIP: 0010:ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151 Call Trace: skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53 nsh_gso_segment+0x54a/0xe10 net/nsh/nsh.c:110 skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53 __skb_gso_segment+0x342/0x510 net/core/gso.c:124 skb_gso_segment include/net/gso.h:83 [inline] validate_xmit_skb+0x857/0x11b0 net/core/dev.c:3950 validate_xmit_skb_list+0x84/0x120 net/core/dev.c:4000 sch_direct_xmit+0xd3/0x4b0 net/sched/sch_generic.c:329 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679 Fixes: d1da932ed4ec ("ipv6: Separate ipv6 offload support") Reported-by: syzbot+af43e647fd835acc02df@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/688a1a05.050a0220.5d226.0008.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Reviewed-by: Dawid Osuchowski Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20250730131738.3385939-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

skbuff: introduce skb_expand_head()

2025-01-09T12:24:59+00:00

[ Upstream commit f1260ff15a71b8fc122b2c9abd8a7abffb6e0168 ] Like skb_realloc_headroom(), new helper increases headroom of specified skb. Unlike skb_realloc_headroom(), it does not allocate a new skb if possible; copies skb->sk on new skb when as needed and frees original skb in case of failures. This helps to simplify ip[6]_finish_output2() and a few other similar cases. Signed-off-by: Vasily Averin Signed-off-by: David S. Miller (cherry picked from commit f1260ff15a71b8fc122b2c9abd8a7abffb6e0168) Signed-off-by: Harshvardhan Jha Signed-off-by: Sasha Levin

inet: inet_defrag: prevent sk release while still in use

2024-10-17T13:07:37+00:00

commit 18685451fc4e546fc0e718580d32df3c0e5c8272 upstream. ip_local_out() and other functions can pass skb->sk as function argument. If the skb is a fragment and reassembly happens before such function call returns, the sk must not be released. This affects skb fragments reassembled via netfilter or similar modules, e.g. openvswitch or ct_act.c, when run as part of tx pipeline. Eric Dumazet made an initial analysis of this bug. Quoting Eric: Calling ip_defrag() in output path is also implying skb_orphan(), which is buggy because output path relies on sk not disappearing. A relevant old patch about the issue was : 8282f27449bf ("inet: frag: Always orphan skbs inside ip_defrag()") [..] net/ipv4/ip_output.c depends on skb->sk being set, and probably to an inet socket, not an arbitrary one. If we orphan the packet in ipvlan, then downstream things like FQ packet scheduler will not work properly. We need to change ip_defrag() to only use skb_orphan() when really needed, ie whenever frag_list is going to be used. Eric suggested to stash sk in fragment queue and made an initial patch. However there is a problem with this: If skb is refragmented again right after, ip_do_fragment() will copy head->sk to the new fragments, and sets up destructor to sock_wfree. IOW, we have no choice but to fix up sk_wmem accouting to reflect the fully reassembled skb, else wmem will underflow. This change moves the orphan down into the core, to last possible moment. As ip_defrag_offset is aliased with sk_buff->sk member, we must move the offset into the FRAG_CB, else skb->sk gets clobbered. This allows to delay the orphaning long enough to learn if the skb has to be queued or if the skb is completing the reasm queue. In the former case, things work as before, skb is orphaned. This is safe because skb gets queued/stolen and won't continue past reasm engine. In the latter case, we will steal the skb->sk reference, reattach it to the head skb, and fix up wmem accouting when inet_frag inflates truesize. Fixes: 7026b1ddb6b8 ("netfilter: Pass socket pointer down through okfn().") Diagnosed-by: Eric Dumazet Reported-by: xingwei lee Reported-by: yue sun Reported-by: syzbot+e5167d7144a62715044c@syzkaller.appspotmail.com Signed-off-by: Florian Westphal Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20240326101845.30836-1-fw@strlen.de Signed-off-by: Paolo Abeni Signed-off-by: Saeed Mirzamohammadi Signed-off-by: Greg Kroah-Hartman

xfrm: Preserve vlan tags for transport mode software GRO

2024-05-17T09:48:06+00:00

[ Upstream commit 58fbfecab965014b6e3cc956a76b4a96265a1add ] The software GRO path for esp transport mode uses skb_mac_header_rebuild prior to re-injecting the packet via the xfrm_napi_dev. This only copies skb->mac_len bytes of header which may not be sufficient if the packet contains 802.1Q tags or other VLAN tags. Worse copying only the initial header will leave a packet marked as being VLAN tagged but without the corresponding tag leading to mangling when it is later untagged. The VLAN tags are important when receiving the decrypted esp transport mode packet after GRO processing to ensure it is received on the correct interface. Therefore record the full mac header length in xfrm*_transport_input for later use in corresponding xfrm*_transport_finish to copy the entire mac header when rebuilding the mac header for GRO. The skb->data pointer is left pointing skb->mac_header bytes after the start of the mac header as is expected by the network stack and network and transport header offsets reset to this location. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Signed-off-by: Paul Davey Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin

netfilter: nf_tables: fix ifdef to also consider nf_tables=m

2023-04-26T09:27:35+00:00

[ Upstream commit c55c0e91c813589dc55bea6bf9a9fbfaa10ae41d ] nftables can be built as a module, so fix the preprocessor conditional accordingly. Fixes: 478b360a47b7 ("netfilter: nf_tables: fix nf_trace always-on with XT_TRACE=n") Reported-by: Florian Fainelli Reported-by: Jakub Kicinski Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

netfilter: br_netfilter: fix recent physdev match breakage

2023-04-26T09:27:34+00:00

[ Upstream commit 94623f579ce338b5fa61b5acaa5beb8aa657fb9e ] Recent attempt to ensure PREROUTING hook is executed again when a decrypted ipsec packet received on a bridge passes through the network stack a second time broke the physdev match in INPUT hook. We can't discard the nf_bridge info strct from sabotage_in hook, as this is needed by the physdev match. Keep the struct around and handle this with another conditional instead. Fixes: 2b272bb558f1 ("netfilter: br_netfilter: disable sabotage_in hook after first suppression") Reported-and-tested-by: Farid BENAMROUCHE Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

net: add inline function skb_csum_is_sctp

2023-01-14T09:16:10+00:00

[ Upstream commit fa82117010430aff2ce86400f7328f55a31b48a6 ] This patch is to define a inline function skb_csum_is_sctp(), and also replace all places where it checks if it's a SCTP CSUM skb. This function would be used later in many networking drivers in the following patches. Suggested-by: Alexander Duyck Signed-off-by: Xin Long Reviewed-by: Alexander Duyck Signed-off-by: Jakub Kicinski Stable-dep-of: db0b124f02ba ("igc: Enhance Qbv scheduling by using first flag bit") Signed-off-by: Sasha Levin

net: switch to storing KCOV handle directly in sk_buff

2023-01-14T09:16:10+00:00

[ Upstream commit fa69ee5aa48b5b52e8028c2eb486906e9998d081 ] It turns out that usage of skb extensions can cause memory leaks. Ido Schimmel reported: "[...] there are instances that blindly overwrite 'skb->extensions' by invoking skb_copy_header() after __alloc_skb()." Therefore, give up on using skb extensions for KCOV handle, and instead directly store kcov_handle in sk_buff. Fixes: 6370cc3bbd8a ("net: add kcov handle to skb extensions") Fixes: 85ce50d337d1 ("net: kcov: don't select SKB_EXTENSIONS when there is no NET") Fixes: 97f53a08cba1 ("net: linux/skbuff.h: combine SKB_EXTENSIONS + KCOV handling") Link: https://lore.kernel.org/linux-wireless/20201121160941.GA485907@shredder.lan/ Reported-by: Ido Schimmel Signed-off-by: Marco Elver Link: https://lore.kernel.org/r/20201125224840.2014773-1-elver@google.com Signed-off-by: Jakub Kicinski Stable-dep-of: db0b124f02ba ("igc: Enhance Qbv scheduling by using first flag bit") Signed-off-by: Sasha Levin

io_uring/af_unix: defer registered files gc to io_uring release

2022-10-26T11:25:55+00:00

[ upstream commit 0091bfc81741b8d3aeb3b7ab8636f911b2de6e80 ] Instead of putting io_uring's registered files in unix_gc() we want it to be done by io_uring itself. The trick here is to consider io_uring registered files for cycle detection but not actually putting them down. Because io_uring can't register other ring instances, this will remove all refs to the ring file triggering the ->release path and clean up with io_ring_ctx_free(). Cc: stable@vger.kernel.org Fixes: 6b06314c47e1 ("io_uring: add file set registration") Reported-and-tested-by: David Bouman Signed-off-by: Pavel Begunkov Signed-off-by: Thadeu Lima de Souza Cascardo [axboe: add kerneldoc comment to skb, fold in skb leak fix] Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman