For lshift and rshift, the shift operations are performed in a loop over
32-bit words. The loop calculates the shifted value and write it to dst,
and then immediately reads from src to calculate the carry for the next
iteration. Because src and dst could point to the same memory location,
the carry is incorrectly calculated using the newly modified dst value
instead of the original src value.
Adding a temporary local variable to cache the original value before
writing to dst and using it for the carry calculation solves the
problem. In addition, partial overlap is rejected from control plane for
all kind of operations including byteorder. This was tested with the
following bytecode:
table test_table ip flags 0 use 1 handle 1
ip test_table test_chain use 3 type filter hook input prio 0 policy accept packets 0 bytes 0 flags 1
ip test_table test_chain 2
[ immediate reg 1 0x44332211 0x88776655 ]
[ bitwise reg 1 = ( reg 1 << 0x08000000 ) ]
[ cmp eq reg 1 0x66443322 0x00887766 ]
[ counter pkts 0 bytes 0 ]
ip test_table test_chain 4 3
[ immediate reg 1 0x44332211 0x88776655 ]
[ bitwise reg 1 = ( reg 1 << 0x08000000 ) ]
[ cmp eq reg 1 0x55443322 0x00887766 ]
[ counter pkts 21794 bytes 1917798 ]
Fixes: 567d746b55 ("netfilter: bitwise: add support for shifts.")
Acked-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
nft_fib6_info_nh_uses_dev() runs from nft_fib6_eval() in softirq under
rcu_read_lock(). fib6_siblings is modified by writers that hold
tb6_lock but do not wait for RCU readers, so the sibling walk should
use list_for_each_entry_rcu(): it adds READ_ONCE() on the ->next
pointer and lets CONFIG_PROVE_RCU_LIST validate the locking.
No functional change for non-debug builds.
Fixes: 1c32b24c23 ("netfilter: nft_fib_ipv6: switch to fib6_lookup")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Florian Westphal <fw@strlen.de>
Luxiao Xu says:
The function compat_mtw_from_user() converts ebtables extensions from
32-bit user structures to kernel native structures. However, it lacks
proper validation of the user-supplied match_size/target_size.
When certain extensions are processed, the kernel-side translation
logic may perform memory accesses based on the extension's expected
size. If the user provides a size smaller than what the extension
requires, it results in an out-of-bounds read as reported by KASAN.
This fix introduces a check to ensure match_size is at least as large
as the extension's required compatsize. This covers matches, watchers,
and targets, while maintaining compatibility with standard targets.
AFAIU this is relevant for matches that need to go though
match->compat_from_user() call. Those that use plain memcpy with the
user-provided size are ok because the caller checks that size vs the
start of the next rule entry offset (which itself is checked vs. total
size copied from userspace).
The ->compat_from_user() callbacks assume they can read compatsize bytes,
so they need this extra check.
Based on an earlier patch from Luxiao Xu.
Fixes: 81e675c227 ("netfilter: ebtables: add CONFIG_COMPAT support")
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Luxiao Xu <rakukuip@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Several parts of network stack rely on iph->ihl validation
done by network stack before PRE_ROUTING.
Disable this feature for user namespaces for now.
tcp option handling is likely safe even for LOCAL_IN, so this
this leaves tcp option mangling via nft_exthdr.c as-is.
I don't think these are the only means to alter packets, but these
appear to be relatively prominent.
This could be relaxed later. Example:
- allow userns for ingress hook.
- allow userns if base is transport header.
Also, we should revalidate or restrict generally:
- Don't allow linklayer writes to spill into network header
- restrict ipv4 and ipv6 to 'known safe' writes, e.g.
saddr/daddr/check/tos
Reported-by: Qi Tang <tpluszz77@gmail.com>
Reported-by: Tong Liu <lyutoon@gmail.com>
Tested-by: Qi Tang <tpluszz77@gmail.com>
Link: https://lore.kernel.org/netfilter-devel/20260515100411.3141-1-fw@strlen.de/
Signed-off-by: Florian Westphal <fw@strlen.de>
With PREEMPT_RCU we get splat:
BUG: using smp_processor_id() in preemptible [..]
caller is cpu_mt+0x53/0xd0 net/netfilter/xt_cpu.c:37
CPU: 1 .. Comm: syz.3.1377 #0 PREEMPT(full)
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
check_preemption_disabled+0xd3/0xe0 lib/smp_processor_id.c:47
cpu_mt+0x53/0xd0 net/netfilter/xt_cpu.c:37
[..]
Just use raw version instead.
This is similar to 14d14a5d29 ("netfilter: nft_meta: use raw_smp_processor_id()").
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Reported-by: syzbot+690d3e3ffa7335ac10eb@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Quoting reporter:
A race between GRE keymap insertion and destruction can corrupt the
kernel list or use a freed object. `nf_ct_gre_keymap_add()` publishes a
new keymap pointer before the embedded `list_head` is linked, while
`nf_ct_gre_keymap_destroy()` can concurrently delete and free that
same object. An unprivileged user can reach this through the PPTP
conntrack helper by racing PPTP control messages or helper teardown,
leading to KASAN-detectable list corruption/UAF in kernel context.
## Root Cause Analysis
`exp_gre()` installs GRE expectations for a PPTP control flow and then
adds two GRE keymap entries [..]
The add path publishes `ct_pptp_info->keymap[dir]` before linking the
embedded list node [..]
Concurrent teardown deletes that partially initialized object.
Make add/destroy symmetric: install both, destroy both while under lock.
Furthermore, we should refuse to publish a new mapping in case ct is going
away, else we may leak the allocation.
The "retrans" detection is strange: existing mapping is checked for key
equality with the new mapping, then for "is on the list" via list walk.
But I can't see how an existing keymap entry can be NOT on list.
Change this to only check if we're asked to map same tuple again -- if so,
skip re-install, else signal failure.
Last, add a bug trap for the keymap list; it has to be empty when namespace
is going away.
Reported-by: Leo Lin <leo@depthfirst.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
synproxy_tstamp_adjust() rewrites the TCP timestamp option in place
and then patches the TCP checksum via inet_proto_csum_replace4() on
the caller-supplied tcphdr pointer. Both ipv4_synproxy_hook() and
ipv6_synproxy_hook() obtain that pointer with skb_header_pointer()
before calling in, so it may either alias skb->head directly or
point at the caller's on-stack _tcph buffer.
Between obtaining the pointer and using it, the function calls
skb_ensure_writable(skb, optend), which on a cloned or non-linear
skb invokes pskb_expand_head() and frees the old skb->head. After
that point the cached th is stale:
caller (ipv[46]_synproxy_hook)
th = skb_header_pointer(skb, ..., &_tcph)
synproxy_tstamp_adjust(skb, protoff, th, ...)
skb_ensure_writable(skb, optend)
pskb_expand_head() /* kfree(old skb->head) */
...
inet_proto_csum_replace4(&th->check, ...)
/* writes into freed head, or
into the caller's stack copy
leaving the on-wire checksum
stale */
The option bytes are written through skb->data and are fine; only
the checksum update goes through th and so lands in the wrong
place. The result is either a write into freed slab memory or a
packet leaving with a checksum that does not match its payload.
Fix by re-deriving th from skb->data + protoff immediately after
skb_ensure_writable() succeeds, so the subsequent checksum update
targets the linear, writable header.
Fixes: 48b1de4c11 ("netfilter: add SYNPROXY core/target")
Assisted-by: kres (claude-opus-4-7)
Signed-off-by: Chris Mason <clm@meta.com>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
An unintended behavior in the TCP conntrack state machine allows a
connection to be forced into the CLOSE state using an RST packet with an
invalid sequence number.
Specifically, after a SYN packet is observed, an RST with an invalid SEQ
can transition the conntrack entry to TCP_CONNTRACK_CLOSE, regardless of
whether the RST corresponds to the expected reply direction. The relevant
code path assumes the RST is a response to an outgoing SYN, but does not
validate packet direction or ensure that a matching SYN was actually sent
in the opposite direction.
As a result, a crafted packet sequence consisting of a SYN followed by an
invalid-sequence RST can prematurely terminate an active NAT entry. This
makes connection teardown easier than intended.
So, tighten the state transition logic to ensure that RST-triggered
CLOSE transitions only occur when the RST is a valid response to a
previously observed SYN in the correct direction.
Cc: stable@vger.kernel.org
Fixes: 9fb9cbb108 ("[NETFILTER]: Add nf_conntrack subsystem.")
Signed-off-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
The ESP out-of-place fast path appends the trailer in esp_output_head()
before esp_output_tail() allocates the destination page frag. The
head-side gate currently checks skb->data_len and tailen separately, but
the tail code allocates a single destination frag from the combined
post-trailer skb->data_len.
Reject the page-frag fast path when the combined aligned length exceeds a
page. Otherwise skb_page_frag_refill() may fall back to a single page while
the destination sg still spans the combined skb->data_len.
Restore this combined-length page gate for both IPv4 and IPv6.
Fixes: 5bd8baab08 ("esp: limit skb_page_frag_refill use to a single page")
Cc: stable@vger.kernel.org
Signed-off-by: Lin Ma <malin89@huawei.com>
Signed-off-by: Chenyuan Mi <michenyuan@huawei.com>
Signed-off-by: Jingguo Tan <tanjingguo@huawei.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
In esp_output_tail(), when esp->inplace is false, the old skb page frags
are replaced with a new page from the xfrm page_frag cache. The source
scatterlist (sg) is built from the old frags before the replacement, and
esp_ssg_unref() is responsible for releasing the old page references
after the crypto operation completes.
However, if the second skb_to_sgvec() call (which builds the destination
scatterlist from the new page) fails, the code jumps to error_free which
only calls kfree(tmp). The old page frag references captured in the
source scatterlist are never released:
1. sg[] is built from old frags via skb_to_sgvec() (no extra get_page)
2. nr_frags is set to 1 and frag[0] is replaced with the new page
3. Second skb_to_sgvec() fails -> goto error_free
4. kfree(tmp) frees the sg[] memory but old frags are not unref'd
5. kfree_skb() only releases frag[0] (the new page), not the old ones
Fix this by adding a bool parameter to esp_ssg_unref() that, when true,
unconditionally unrefs the source scatterlist frags without checking
req->src and req->dst, since those fields are not yet initialized by
aead_request_set_crypt() at the point of the error. Existing callers
pass false to preserve the original behavior.
The same issue exists in both esp4 and esp6 as the code is identical.
Fixes: cac2661c53 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Alessandro Schino <7991aleschino@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Pull networking fixes from Jakub Kicinski:
"Including fixes from Bluetooth, wireless and netfilter.
Craziness continues with no end in sight. Even discounting the driver
revert this is a pretty huge PR for standards of the previous era. I'd
speculate - we haven't seen the worst of it, yet. Good news, I guess,
is that so far we haven't seen many (any?) cases of "AI reported a
bug, we fixed it and a real user regressed".
Current release - fix to a fix:
- Bluetooth: btmtk: accept too short WMT FUNC_CTRL events
- vsock/virtio: relax the recently added memory limit a little
Current release - regressions:
- IB/IPoIB: make sure IB drivers always use async set_rx_mode since
some (mlx5) are now required to use it due to locking changes
Previous releases - regressions:
- udp: fix UDP length on last GSO_PARTIAL segment
- af_unix: fix UAF read of tail->len in unix_stream_data_wait()
- tcp: fix stale per-CPU tcp_tw_isn leak enabling ISN prediction
- mlx5e: fix unlocked writing to ICOSQ, breaking AF_XDP
Previous releases - always broken:
- tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
- ipv4: raw: reject IP_HDRINCL packets with ihl < 5
- Bluetooth: a lot of locking and concurrency fixes (as always)
- batman-adv (mesh wireless networking): a lot of random fixes for
issues reported by security researchers and Sashiko
- netfilter: same thing, a lot of small security-ish fixes all over
the place, nothing really stands out
Misc:
- bring back the old 3c509 driver, Maciej wants to maintain it"
* tag 'net-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (187 commits)
net: enetc: avoid VF->PF mailbox timeout during SR-IOV teardown
net: enetc: fix init and teardown order to prevent use of unsafe resources
net: enetc: fix unbounded loop and interrupt handling in VF-to-PF messaging
net: enetc: fix DMA write to freed memory in enetc_msg_free_mbx()
net: enetc: fix race condition in VF MAC address configuration
net: enetc: fix TOCTOU race and validate VF MAC address
net: enetc: add ratelimiting to VF mailbox error messages
net: enetc: fix missing error code when pf->vf_state allocation fails
net: enetc: fix incorrect mailbox message status returned to VFs
net: bridge: prevent too big nested attributes in br_fill_linkxstats()
l2tp: use list_del_rcu in l2tp_session_unhash
net: bcmgenet: keep RBUF EEE/PM disabled
ethernet: 3c509: Fix most coding style issues
ethernet: 3c509: Update documentation to match MAINTAINERS
ethernet: 3c509: Add GPL 2.0 SPDX license identifier
ethernet: 3c509: Fix AUI transceiver type selection
Revert "drivers: net: 3com: 3c509: Remove this driver"
tools: ynl: support listening on all nsids
net: gro: don't merge zcopy skbs
pds_core: ensure null-termination for firmware version strings
...
Commit 7b546bd899 ("sunrpc/cache: improve RCU safety in
cache_list walking.") changed the tail of __cache_seq_start()
to unconditionally store
*pos = ((long long)hash << 32) + 1
before returning, dropping a prior "hash >= cd->hash_size"
guard. When the while loop exits because every remaining
bucket was empty, hash equals cd->hash_size, so the stored
*pos is one position past the table's last valid bucket.
seq_read_iter() caches that index in m->index. A subsequent
pread(2) at the same file offset skips traverse() and hands
the stored index back to __cache_seq_start(), which decodes
hash = cd->hash_size and dereferences
cd->hash_table[cd->hash_size] -- one hlist_head past the end
of the kzalloc'd table.
KASAN reports an eight-byte slab-out-of-bounds read at the
tail of the 2048-byte hash_table allocation for the NFSD
export cache (EXPORT_HASHMAX * sizeof(struct hlist_head) ==
256 * 8).
Reject an input hash that is out of range before touching the
hash table. cache_seq_next() already bounds-checks its own
loop; the start routine needs to be symmetric.
Reported-by: syzbot+60cfa08822470bbebe44@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=60cfa08822470bbebe44
Fixes: 7b546bd899 ("sunrpc/cache: improve RCU safety in cache_list walking.")
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Johannes Berg says:
====================
Quite a few more updates:
- cfg80211/mac80211:
- various security(-ish) fixes
- fix A-MSDU subframe handling
- fix multi-link element parsing
- ath10: avoid sending commands to dead device
- ath11k:
- fix WMI buffer leaks on error conditions
- fix UAF in RX MSDU coalesce path
- allow peer ID 0 on RX path (legal for mobile devices)
- reinitialize shared SRNG pointers on restart
- ath12k:
- fix 20 MHz-only parsing of EHT-MCS map
- iwlwifi:
- fix TSO segmentation explosion
- don't TX to dead device
- fix warning in WoWLAN
- fix TX rates on old devices
- disconnect on beacon loss only if also no other traffic
- fill NULL-ptr deref
- fix STEP_URM hardware access
* tag 'wireless-2026-05-21' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless: (24 commits)
wifi: cfg80211: wext: validate chandef in monitor mode
wifi: mac80211: consume only present negotiated TTLM maps
wifi: wilc1000: fix dma_buffer leak on bus acquire failure
wifi: mac80211: capture fast-RX rate before mesh reuses skb->cb
wifi: mac80211: fix multi-link element inheritance
wifi: mac80211: fix MLE defragmentation
wifi: mac80211: don't override max_amsdu_subframes
wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs
wifi: ath12k: fix EHT TX MCS limitation due to wrong 20 MHz-only parsing
wifi: ath11k: clear shared SRNG pointer state on restart
wifi: ath11k: fix use after free in ath11k_dp_rx_msdu_coalesce()
wifi: ath11k: fix peer resolution on rx path when peer_id=0
wifi: iwlwifi: mld: disconnect only after 6 beacons without Rx
wifi: iwlwifi: mld: don't WARN on WoWLAN suspend w/o BSS vif
wifi: iwlwifi: use correct function to read STEP_URM register
wifi: iwlwifi: mvm: fix driver-set TX rates on old devices
wifi: iwlwifi: mld: don't dereference a pointer before NULL checking it
wifi: iwlwifi: mld: stop TX during firmware restart
wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
wifi: ath10k: skip WMI and beacon transmission when device is wedged
...
====================
Link: https://patch.msgid.link/20260521152903.374070-3-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
An unprivileged local user can pin a host CPU indefinitely in
l2tp_session_get_by_ifname() by issuing L2TP_CMD_SESSION_GET on
L2TP_ATTR_IFNAME concurrently with L2TP_CMD_SESSION_CREATE and
L2TP_CMD_SESSION_DELETE on the same tunnel. All three commands take
GENL_UNS_ADMIN_PERM, so CAP_NET_ADMIN in the netns user namespace
suffices; on any host that has l2tp_core loaded the trigger is
reachable from a standard `unshare -Urn` sandbox.
l2tp_session_unhash() removes a session from tunnel->session_list
with list_del_init(), but that list is walked by
l2tp_session_get_by_ifname() with list_for_each_entry_rcu() under
rcu_read_lock_bh(). list_del_init() leaves the deleted entry's
next/prev self-pointing; a reader that has loaded the entry and
then advances pos->list.next reads &session->list, container_of()s
back to the same session, and list_for_each_entry_rcu() never
reaches the list head. The CPU stays in strcmp() inside the
walker, with BH and preemption disabled, so RCU grace periods on
the host stall behind it and the wedged thread cannot be killed
(SIGKILL is delivered on syscall return).
Use list_del_rcu() to match the existing list_add_rcu() in
l2tp_session_register(); the deleted session remains visible to
in-flight walkers with consistent next/prev pointers until
kfree_rcu() in l2tp_session_free() releases it. tunnel->session_list
has exactly one list_del_init() call site; the list_del_init
(&session->clist) at l2tp_core.c:533 operates on the per-collision
list, which is not walked under RCU. list_empty(&session->list) is
not used anywhere in net/l2tp/ after the unhash point, so dropping
the post-delete self-init is safe; the fix has no userspace-visible
behavior change.
Fixes: 89b768ec2d ("l2tp: use rcu list add/del when updating lists")
Cc: stable@vger.kernel.org # 6.11+
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260518183447.64078-1-michael.bommarito@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
skb_gro_receive() can currently copy frags between the source and GRO
skb, without checking the zerocopy status, and in particular the
SKBFL_MANAGED_FRAG_REFS flag.
When SKBFL_MANAGED_FRAG_REFS is set, the skb doesn't hold a reference
on the pages in shinfo->frags. Appending those frags to another skb's
frags without fixing up the page refcount can lead to UAF.
When either the last skb in the GRO chain (the one we would append
frags to) or the source skb is zerocopy, don't merge the skbs.
Fixes: 753f1ca4e1 ("net: introduce managed frags infrastructure")
Reported-by: Huzaifa Sidhpurwala <huzaifas@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/c3b7f906bbfcbdfd7b4fa9d6c18a438870df85be.1779307748.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reported by Sashiko:
In ipv6_hop_ioam(), the hdr pointer is initialized to point into the
skb's linear data buffer. Later, the code calls skb_ensure_writable(),
which might reallocate the buffer:
if (skb_ensure_writable(skb, optoff + 2 + hdr->opt_len))
goto drop;
/* Trace pointer may have changed */
trace = (struct ioam6_trace_hdr *)(skb_network_header(skb)
+ optoff + sizeof(*hdr));
ioam6_fill_trace_data(skb, ns, trace, true);
ioam6_event(IOAM6_EVENT_TRACE, dev_net(skb->dev),
GFP_ATOMIC, (void *)trace, hdr->opt_len - 2);
If the skb is cloned or lacks sufficient linear headroom,
skb_ensure_writable() will invoke pskb_expand_head(), which reallocates
the skb's data buffer and frees the old one, invalidating pointers to
it. While the code recalculates the trace pointer immediately after the
call to skb_ensure_writable(), it fails to recalculate the hdr pointer.
This patch fixes the above by recalculating the hdr pointer before
passing hdr->opt_len to ioam6_event(), so that we avoid any UaF.
Fixes: f655c78d62 ("net: exthdrs: ioam6: send trace event")
Cc: stable@vger.kernel.org
Signed-off-by: Justin Iurman <justin.iurman@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260520124242.32320-1-justin.iurman@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
__netpoll_send_skb() always transmits through np->dev and queues busy
packets on np->dev->npinfo->txq, but it leaves skb->dev unchanged.
Stacked callers such as DSA and macvlan can reach netpoll with skb->dev
still naming the upper device while np->dev is the lower device that
owns the netpoll state.
If the skb has to be deferred, queue_process() later dequeues it from
the lower device's txq but retries it through skb->dev. That can
re-enter the upper ndo_start_xmit path on an already transformed skb,
and if the upper device disappears before the lower txq drains the
workqueue can dereference a stale skb->dev pointer.
The buggy scenario involves two paths, with each column showing the
order within that path:
path A label: netpoll enqueue path path B label: upper-device teardown
1. Stacked xmit calls netpoll 1. Teardown unregisters the upper
with lower np->dev and upper net_device while lower npinfo
skb->dev. stays alive.
2. __netpoll_send_skb() uses 2. netdev_release() runs for the
np->dev->npinfo as the txq upper net_device.
owner.
3. Busy transmit queues the skb 3. The lower txq still owns the
on that lower txq with upper deferred skb.
skb->dev.
4. queue_process() drains the 4. queue_process() dereferences
lower txq and reads skb->dev. that stale upper skb->dev.
Normalize skb->dev to np->dev after loading np->dev from the netpoll
instance, before either the direct transmit path or the fallback enqueue.
This keeps the queued skb in the same device and txq domain as the
netpoll state that owns it.
KASAN report as below:
KASAN slab-use-after-free in queue_process+0x7c/0x480
Workqueue: events queue_process
The buggy address belongs to the object at ffff88810906c000 which belongs
to the cache kmalloc-4k of size 4096
The buggy address is located 168 bytes inside of freed 4096-byte region
[ffff88810906c000, ffff88810906d000)
Read of size 8
Call trace:
dump_stack_lvl+0x73/0xb0 (?:?)
print_report+0xd1/0x620 (?:?)
srso_alias_return_thunk+0x5/0xfbef5 (?:?)
__virt_addr_valid+0x215/0x420 (?:?)
kasan_complete_mode_report_info+0x64/0x200 (?:?)
kasan_report+0xf7/0x130 (?:?)
queue_process+0x7c/0x480 (net/core/netpoll.c:88)
kasan_check_range+0x10c/0x1c0 (?:?)
__kasan_check_read+0x15/0x20 (?:?)
process_one_work+0x8b7/0x1af0 (kernel/workqueue.c:3200)
assign_work+0x170/0x3f0 (?:?)
worker_thread+0x574/0xf10 (?:?)
_raw_spin_unlock_irqrestore+0x4b/0x60 (?:?)
trace_hardirqs_on+0x2a/0x180 (?:?)
kthread+0x2fc/0x3f0 (?:?)
ret_from_fork+0x58b/0x830 (?:?)
__switch_to+0x58e/0xe90 (?:?)
__switch_to_asm+0x39/0x70 (?:?)
ret_from_fork_asm+0x1a/0x30 (?:?)
Freed by task stack:
kasan_save_stack+0x3d/0x60 (?:?)
kasan_save_track+0x18/0x40 (?:?)
kasan_save_free_info+0x3f/0x60 (?:?)
__kasan_slab_free+0x48/0x70 (?:?)
kfree+0x20e/0x4e0 (?:?)
kvfree+0x31/0x40 (?:?)
netdev_release+0x71/0x90 (net/core/net-sysfs.c:2227)
device_release+0xd2/0x250 (?:?)
kobject_put+0x181/0x4c0 (lib/kobject.c:730)
netdev_run_todo+0x700/0x1000 (net/core/dev.c:11666)
rtnl_dellink+0x396/0xc00 (net/core/rtnetlink.c:3558)
rtnetlink_rcv_msg+0x740/0xc20 (net/core/rtnetlink.c:6897)
netlink_rcv_skb+0x147/0x3a0 (?:?)
rtnetlink_rcv+0x19/0x20 (net/core/rtnetlink.c:7021)
netlink_unicast+0x4d1/0x830 (net/netlink/af_netlink.c:1327)
netlink_sendmsg+0x840/0xe10 (net/netlink/af_netlink.c:1812)
____sys_sendmsg+0x8a7/0xb50 (?:?)
___sys_sendmsg+0x104/0x190 (?:?)
__sys_sendmsg+0x135/0x1d0 (?:?)
__x64_sys_sendmsg+0x7b/0xc0 (?:?)
x64_sys_call+0x205c/0x2130 (?:?)
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?)
Fixes: 5de4a473bd ("netpoll queue cleanup")
Signed-off-by: Zhang Cen <rollkingzzc@gmail.com>
Link: https://patch.msgid.link/20260519104647.3517990-1-rollkingzzc@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ip6_route_init() registers ip6_route_dev_notifier before registering the
IPv6 route BPF iterator target. If bpf_iter_register() fails after the
notifier has been registered, the error path currently jumps to
out_register_late_subsys and unwinds the RTNL handlers and pernet route
state without removing the notifier from the netdevice notifier chain.
This leaves ip6_route_dev_notify() callable after the IPv6 route state it
uses has been torn down. Add a separate unwind label for the BPF iterator
failure path and unregister the netdevice notifier before continuing with
the existing cleanup.
Fixes: 138d0be35b ("net: bpf: Add netlink and ipv6_route bpf_iter targets")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260520030329.1061183-1-dbgh9129@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The networking receive path is usually run from softirq context, but
protocols that take the socket lock may have packets stored in the
backlog and processed later from process context. In that case
release_sock() -> __release_sock() drops the slock with spin_unlock_bh()
and then calls sk->sk_backlog_rcv() with bottom halves enabled.
Typical sk_backlog_rcv handlers process the socket whose backlog is
being drained, so the BH state at entry is irrelevant for the slocks
they touch. pep_do_rcv() is different: when the inbound skb targets an
existing PEP pipe, it forwards the skb to a different *child* socket
via sk_receive_skb(). That helper takes the child slock with
bh_lock_sock_nested(), which is just spin_lock_nested() and assumes BH
is already off. The same child slock therefore ends up acquired with
BH on (process path) and with BH off (softirq path):
process context softirq context
--------------- ---------------
release_sock(listener) __netif_receive_skb()
__release_sock() phonet_rcv()
spin_unlock_bh() __sk_receive_skb(listener)
[BH now ENABLED] [BH already disabled]
sk_backlog_rcv: sk_backlog_rcv:
pep_do_rcv() pep_do_rcv()
sk_receive_skb(child) sk_receive_skb(child)
bh_lock_sock_nested(child) bh_lock_sock_nested(child)
=> SOFTIRQ-ON-W => IN-SOFTIRQ-W
Lockdep flags this as inconsistent lock state, and it can become a real
self-deadlock if a softirq on the same CPU tries to receive to the same
child socket while its slock is held in the BH-enabled path:
WARNING: inconsistent lock state
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
(slock-AF_PHONET/1){+.?.}-{3:3}, at: __sk_receive_skb+0x1cf/0x900
__sk_receive_skb net/core/sock.c:563
sk_receive_skb include/net/sock.h:2022 [inline]
pep_do_rcv net/phonet/pep.c:675
sk_backlog_rcv include/net/sock.h:1190
__release_sock net/core/sock.c:3216
release_sock net/core/sock.c:3815
pep_sock_accept net/phonet/pep.c:879
Wrap the forwarded sk_receive_skb() in local_bh_disable() /
local_bh_enable() so the child slock is always acquired with BH off.
local_bh_disable() nests safely on the softirq path.
Discovered via in-house syzkaller fuzzing; the same root cause also
on the linux-6.1.y syzbot dashboard as extid 44f0626dd6284f02663c.
Reproduced under KASAN + LOCKDEP + PROVE_LOCKING, reproducer:
https://pastebin.com/A3t8xzCR
Fixes: 9641458d3e ("Phonet: Pipe End Point for Phonet Pipes protocol")
Link: https://syzkaller.appspot.com/bug?extid=44f0626dd6284f02663c
Cc: stable@vger.kernel.org
Signed-off-by: Zijing Yin <yzjaurora@gmail.com>
Acked-by: Rémi Denis-Courmont <remi@remlab.net>
Reported-by: syzbot+9f4a135646b66c509935@syzkaller.appspotmail.com
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260519172635.86304-1-yzjaurora@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After commit 059b7dbd20 ("vsock/virtio: fix potential unbounded skb
queue"), virtio_transport_inc_rx_pkt() subtracts per-skb overhead from
buf_alloc when checking whether a new packet fits. This reduces the
effective receive buffer below what the user configured via
SO_VM_SOCKETS_BUFFER_SIZE, causing legitimate data packets to be
silently dropped and applications that rely on the full buffer size
to deadlock.
Also, the reduced space is not communicated to the remote peer, so
its credit calculation accounts more credit than the receiver will
actually accept, causing data loss (there is no retransmission).
With this approach we currently have failures in
tools/testing/vsock/vsock_test.c. Test 18 sometimes fails, while
test 22 always fails in this way:
18 - SOCK_STREAM MSG_ZEROCOPY...hash mismatch
22 - SOCK_STREAM virtio credit update + SO_RCVLOWAT...send failed:
Resource temporarily unavailable
Fix by allowing at most `buf_alloc * 2` as the total budget for payload
plus skb overhead in virtio_transport_inc_rx_pkt(), similar to how
SO_RCVBUF is doubled to reserve space for sk_buff metadata.
This preserves the full buf_alloc for payload under normal operation,
while still bounding the skb queue growth.
With this patch, all tests in tools/testing/vsock/vsock_test.c are
now passing again.
Fixes: 059b7dbd20 ("vsock/virtio: fix potential unbounded skb queue")
Cc: stable@vger.kernel.org
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20260518090656.134588-3-sgarzare@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When there is no more space to queue an incoming packet, the packet is
silently dropped. This causes data loss without any notification to
either peer, since there is no retransmission.
Under normal circumstances, this should never happen. However, it could
happen if the other peer doesn't respect the credit, or if the skb
overhead, which we recently began to take into account with commit
059b7dbd20 ("vsock/virtio: fix potential unbounded skb queue"),
is too high.
Fix this by resetting the connection and setting the local socket error
to ENOBUFS when virtio_transport_recv_enqueue() can no longer queue a
packet, so both peers are explicitly notified of the failure rather than
silently losing data.
Fixes: ae6fcfbf5f ("vsock/virtio: discard packets if credit is not respected")
Cc: stable@vger.kernel.org
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20260518090656.134588-2-sgarzare@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Two frag-transfer helpers (__pskb_copy_fclone() and skb_shift()) fail
to propagate the SKBFL_SHARED_FRAG bit in skb_shinfo()->flags when
moving frags from source to destination. __pskb_copy_fclone() defers
the rest of the shinfo metadata to skb_copy_header() after copying
frag descriptors, but that helper only carries over gso_{size,segs,
type} and never touches skb_shinfo()->flags; skb_shift() moves frag
descriptors directly and leaves flags untouched. As a result, the
destination skb keeps a reference to the same externally-owned or
page-cache-backed pages while reporting skb_has_shared_frag() as
false.
The mismatch is harmful in any in-place writer that uses
skb_has_shared_frag() to decide whether shared pages must be detoured
through skb_cow_data(). ESP input is one such writer (esp4.c,
esp6.c), and a single nft 'dup to <local>' rule -- or any other
nf_dup_ipv4() / xt_TEE caller -- is enough to land a pskb_copy()'d
skb in esp_input() with the marker stripped, letting an unprivileged
user write into the page cache of a root-owned read-only file via
authencesn-ESN stray writes.
Set SKBFL_SHARED_FRAG on the destination whenever frag descriptors
were actually moved from the source. skb_copy() and skb_copy_expand()
share skb_copy_header() too but linearize all paged data into freshly
allocated head storage and emerge with nr_frags == 0, so
skb_has_shared_frag() returns false on its own; they need no change.
The same omission exists in skb_gro_receive() and skb_gro_receive_list().
The former moves the incoming skb's frag descriptors into the
accumulator's last sub-skb via two paths (a direct frag-move loop and
the head_frag + memcpy path); the latter chains the incoming skb whole
onto p's frag_list. Downstream skb_segment() reads only
skb_shinfo(p)->flags, and skb_segment_list() reuses each sub-skb's
shinfo as the nskb -- both p and lp must carry the marker.
The same omission also exists in tcp_clone_payload(), which builds an
MTU probe skb by moving frag descriptors from skbs on sk_write_queue
into a freshly allocated nskb. The helper falls into the same family
and warrants the same fix for consistency; no TCP TX-side in-place
writer is currently known to reach a user page through this gap, but
a future consumer depending on the marker would regress silently.
The same omission exists in skb_segment(): the per-iteration flag
merge takes only head_skb's flag, and the inner switch that rebinds
frag_skb to list_skb on head_skb-frags exhaustion does not fold the
new frag_skb's flag into nskb. Fold frag_skb's flag at both sites
so segments drawing frags from frag_list members carry the marker.
Fixes: cef401de7b ("net: fix possible wrong checksum generation")
Fixes: f4c50a4034 ("xfrm: esp: avoid in-place decrypt on shared skb frags")
Suggested-by: Sabrina Dubroca <sd@queasysnail.net>
Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Suggested-by: Lin Ma <malin89@huawei.com>
Suggested-by: Jingguo Tan <tanjingguo@huawei.com>
Suggested-by: Aaron Esau <aaron1esau@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Tested-by: Rajat Gupta <rajat.gupta@oss.qualcomm.com>
Link: https://patch.msgid.link/ageeJfJHwgzmKXbh@v4bel
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Blamed commit moved the TIME_WAIT-derived ISN from the skb control
block to a per-CPU variable, assuming the value would always be consumed
by tcp_conn_request() for the same packet that wrote it. That assumption
is violated by multiple drop paths between the producer
(__this_cpu_write(tcp_tw_isn, isn) in tcp_v{4,6}_rcv()) and the consumer
(tcp_conn_request()):
- min_ttl / min_hopcount check
- xfrm policy check
- tcp_inbound_hash() MD5/AO mismatch
- tcp_filter() eBPF/SO_ATTACH_FILTER drop
- th->syn && th->fin discard in tcp_rcv_state_process() TCP_LISTEN
- psp_sk_rx_policy_check() in tcp_v{4,6}_do_rcv()
- tcp_checksum_complete() in tcp_v{4,6}_do_rcv()
- tcp_v{4,6}_cookie_check() returning NULL
When a packet is dropped on any of these paths, tcp_tw_isn is left set.
The next SYN processed on the same CPU then consumes the non zero value in
tcp_conn_request(), receiving a potentially predictable ISN.
This patch moves back tcp_tw_isn to skb->cb[], getting rid of the per-cpu
variable.
Note that tcp_v{4,6}_fill_cb() do not set it.
Very litle impact on overall code size/complexity:
$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/0 grow/shrink: 2/1 up/down: 8/-15 (-7)
Function old new delta
tcp_v6_rcv 3038 3042 +4
tcp_v4_rcv 3035 3039 +4
tcp_conn_request 2938 2923 -15
Total: Before=24436060, After=24436053, chg -0.00%
Fixes: 41eecbd712 ("tcp: replace TCP_SKB_CB(skb)->tcp_tw_isn with a per-cpu field")
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260519084611.2485277-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
vmci_transport_recv_connecting_server() returned err = 0 for a peer
RST in its default switch arm:
err = pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST ? 0 : -EINVAL;
That made vmci_transport_recv_listen() skip vsock_remove_pending(),
leaving the pending socket on the listener's pending_links with
sk_state = TCP_CLOSE while destroy: still dropped the explicit
reference taken before schedule_delayed_work().
One second later vsock_pending_work() observed is_pending=true and
performed full cleanup: vsock_remove_pending() then the two trailing
sock_put(sk) calls -- the first reached refcount 0 and __sk_freed
the socket, and the second wrote into the freed object:
BUG: KASAN: slab-use-after-free in refcount_warn_saturate
Write of size 4 at addr ffff88800b1cac80 by task kworker
Workqueue: events vsock_pending_work
Treat peer RST like any other unexpected packet type (err = -EINVAL).
All destroy: arms now return err < 0, so vmci_transport_recv_listen()
removes pending from pending_links synchronously and
vsock_pending_work() takes the is_pending=false / !rejected branch,
dropping only its own work reference. This also closes the
multi-packet race Sashiko reported on v2: pending is removed from
the list before any subsequent packet can find it.
The pre-existing sk_acceptq_removed() gap on the err < 0 path of
vmci_transport_recv_listen() that Sashiko also noted is not
introduced or changed by this patch.
Tested on lts-6.12.79 with KASAN: 52/100 unpatched -> 0/100 patched.
Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Cc: stable@vger.kernel.org
Signed-off-by: Minh Nguyen <minhnguyen.080505@gmail.com>
Acked-by: Bryan Tan <bryan-bt.tan@broadcom.com>
Link: https://patch.msgid.link/20260519102310.237181-1-minhnguyen.080505@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_devmem_bind_dmabuf() trusts dmabuf->size and sg_dma_len() to be
PAGE_SIZE multiples without checking:
- tx_vec is sized dmabuf->size / PAGE_SIZE, and
net_devmem_get_niov_at() only bounds-checks virt_addr < dmabuf->size
before indexing tx_vec[virt_addr / PAGE_SIZE]. With size =
N*PAGE_SIZE + r (1 <= r < PAGE_SIZE), sendmsg() at iov_base =
N*PAGE_SIZE passes the bound check and reads tx_vec[N] -- one past.
- owner->area.num_niovs = len / PAGE_SIZE while gen_pool_add_owner()
covers the full byte len, so a non-page-multiple non-final sg
desyncs num_niovs from the gen_pool region for every later sg, on
both RX and TX.
dma-buf does not require page-aligned sizes, so the bind path has to
enforce what its own indexing assumes. Reject both with -EINVAL.
The size check is TX-only (only tx_vec is sized off dmabuf->size); the
SG-length check covers both directions.
Fixes: bd61848900 ("net: devmem: Implement TX path")
Cc: stable@vger.kernel.org
Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20260519203530.66310-1-devnexen@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Luiz Augusto von Dentz says:
====================
bluetooth pull request for net:
- hci_sync: Fix not setting mask for HCI_EVT_LE_ALL_REMOTE_FEATURES_COMPLETE
- L2CAP: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del()
- ISO: drop ISO_END frames received without prior ISO_START
- MGMT: validate Add Extended Advertising Data length
- bnep: Fix UAF read of dev->name
- btmtk: fix urb->setup_packet leak in error paths
- btintel_pcie: Fix incorrect MAC access programming
- hci_uart: fix UAFs and race conditions in close and init paths
* tag 'for-net-2026-05-20' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth:
Bluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del()
Bluetooth: hci_uart: fix UAFs and race conditions in close and init paths
Bluetooth: MGMT: validate Add Extended Advertising Data length
Bluetooth: btmtk: fix urb->setup_packet leak in error paths
Bluetooth: ISO: drop ISO_END frames received without prior ISO_START
Bluetooth: btintel_pcie: Fix incorrect MAC access programming
Bluetooth: hci_sync: Fix not setting mask for HCI_EVT_LE_ALL_REMOTE_FEATURES_COMPLETE
Bluetooth: bnep: Fix UAF read of dev->name
====================
Link: https://patch.msgid.link/20260520204959.2902497-1-luiz.dentz@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk_psock_strp_data_ready() already checks tls_sw_has_ctx_rx() and
defers to psock->saved_data_ready when a TLS RX context is present,
avoiding a conflict with the TLS strparser's ownership of the receive
queue (commit e91de6afa8, "bpf: Fix running sk_skb program types
with ktls").
sk_psock_verdict_data_ready() has no equivalent guard. When a socket
is inserted into a sockmap (BPF_SK_SKB_VERDICT) before TLS RX is
configured, tls_sw_strparser_arm() saves sk_psock_verdict_data_ready
as rx_ctx->saved_data_ready. On data arrival:
tls_data_ready -> tls_strp_data_ready -> tls_rx_msg_ready
-> saved_data_ready() = sk_psock_verdict_data_ready()
-> tcp_read_skb() drains sk_receive_queue via __skb_unlink()
without calling tcp_eat_skb(), so copied_seq is not advanced.
tls_strp_msg_load() then finds tcp_inq() >= full_len (stale), calls
tcp_recv_skb() on the now-empty queue, hits WARN_ON_ONCE(!first), and
returns with rx_ctx->strp.anchor.frag_list pointing at a psock-owned
(potentially freed) skb. tls_decrypt_sg() subsequently walks that
frag_list: use-after-free.
Apply the same fix as sk_psock_strp_data_ready(): if a TLS RX context
is present, call psock->saved_data_ready (sock_def_readable) to wake
recv() waiters and return immediately, leaving the receive queue
untouched. TLS retains sole ownership of the queue and decrypts the
record normally through tls_sw_recvmsg().
Fixes: ef5659280e ("bpf, sockmap: Allow skipping sk_skb parser program")
Signed-off-by: Xingwang Xiang <v3rdant.xiang@gmail.com>
Link: https://patch.msgid.link/20260517145630.20521-2-v3rdant.xiang@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This improves the fix for CVE-2026-43500.
Fix the pagecache corruption from in-place decryption of a DATA packet
transmitted locally by splice() by getting rid of the packet sharing in the
I/O thread and unconditionally extracting the packet content into a bounce
buffer in which the buffer is decrypted. recvmsg() (or the kernel
equivalent) then copies the data from the bounce buffer to the destination
buffer. The sk_buff then remains unmodified.
This has an additional advantage in that the packet is then arranged in the
buffer with the correct alignment required for the crypto algorithms to
process directly. The performance of the crypto does seem to be a little
faster and, surprisingly, the unencrypted performance doesn't seem to
change much - possibly due to removing complexity from the I/O thread.
Yet another advantage is that the I/O thread doesn't have to copy packets
which would slow down packet distribution, ACK generation, etc..
The buffer belongs to the call and is allocated initially at 2K,
sufficiently large to hold a whole jumbo subpacket, but the buffer will be
increased in size if needed. However, to take this work, MSG_PEEK may
cause a later packet to be decrypted into the buffer, in which case the
earlier one will need re-decrypting for a subsequent recvmsg().
Note that rx_pkt_offset may legitimately see 0 as a valid offset now, so
switch to using USHRT_MAX to indicate an invalid offset.
Note also that I would generally prefer to replace the buffers of the
current sk_buff with a new kmalloc'd buffer of the right size, ditching the
old data and frags as this makes the handling of MSG_PEEK easier and
removes the re-decryption issue, but this looks like quite a complicated
thing to achieve. skb_morph() looks half way to what I want, but I don't
want to have to allocate a new sk_buff.
Fixes: d0d5c0cd1e ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Closes: https://lore.kernel.org/r/afKV2zGR6rrelPC7@v4bel/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: Jiayuan Chen <jiayuan.chen@linux.dev>
cc: linux-afs@lists.infradead.org
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
Link: https://patch.msgid.link/20260515230516.2718212-3-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Recent commit changed the semantics from NOT_VALID to VALID.
I didn't realize that the flags are not stored atomically
with the entry in XArray. There's still a race of reader
observing a VALID mark for a slot, getting interrupted,
writer replacing the entry with a different one, reader
continuing, fetching the entry which is now a different
pointer than the pointer for which VALID was meant.
The biggest consequence of this is that we may see a UAF
since net_shaper_rollback() assumed that entries without
VALID can be freed without observing RCU.
Looks like the XArray marks are buying us nothing at this
point. Let's convert the code to an explicit valid field.
The smp_load_acquire() / smp_store_release() barriers are
marginally cleaner.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: 93954b40f6 ("net-shapers: implement NL set and delete operations")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260515221325.1685455-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As previously discussed we don't care about making the shaper
state fully RCU-compliant because the hierarchy itself can't
be dumped in one go over Netlink. Let's annotate the reads
and writes to make that clear.
The field-by-field assignments will also be useful for the
next commit which adds explicit "valid" field (which we don't
want to override with the current full struct assignment).
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260515221325.1685455-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The cited commit started using msslen for uh->len, but still uses newlen
to adjust uh->check. Although the checksum is ignored in most cases due
to the hardware offload, __udp_gso_segment attempts to maintain the
correct one. Fix uh->check and adjust it by the right value.
Additionally, after the fix, newlen becomes assigned and unused before
the loop. The code can be simplified a bit if mss adjustment is dropped,
so that newlen becomes equal to msslen before the loop, and msslen can
be also dropped, saving a few lines of code.
This brings us back to one variable, drops an unneeded arithmetic for
mss, and fixes the UDP checksum.
Fixes: b10b446ce7 ("udp: gso: Use single MSS length in UDP header for GSO_PARTIAL")
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Link: https://patch.msgid.link/20260518062250.3019914-2-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
bt_accept_dequeue() unlinks a not-yet-accepted child from the parent
accept queue and release_sock()s it before returning, so the returned
sk has no caller reference and is unlocked.
l2cap_sock_cleanup_listen() walks these children on listening-socket
close. A concurrent HCI disconnect drives hci_rx_work ->
l2cap_conn_del() which runs l2cap_chan_del() + l2cap_sock_kill() and
frees the child sk and its l2cap_chan; cleanup_listen() then uses both:
BUG: KASAN: slab-use-after-free in l2cap_sock_kill
l2cap_sock_kill / l2cap_sock_cleanup_listen / __x64_sys_close
Freed by: l2cap_conn_del -> l2cap_sock_close_cb -> l2cap_sock_kill
This is distinct from the two fixes already in this area: commit
e83f5e24da ("Bluetooth: serialize accept_q access") serialises the
accept_q list/poll and takes temporary refs inside bt_accept_dequeue(),
and CVE-2025-39860 serialises the userspace close()/accept() race by
calling cleanup_listen() under lock_sock() in l2cap_sock_release().
Neither covers l2cap_conn_del() running from hci_rx_work, so this UAF
still reproduces on current bluetooth/master.
Take the reference at the source: bt_accept_dequeue() does sock_hold()
while sk is still locked, before release_sock(); callers sock_put().
cleanup_listen() pins the chan with l2cap_chan_hold_unless_zero() under
a brief child sk lock (serialising vs l2cap_sock_teardown_cb()), drops
it before l2cap_chan_lock(), and skips a duplicate l2cap_sock_kill() on
SOCK_DEAD. conn->lock is not taken here: cleanup_listen() runs under
the parent sk lock and that would invert
conn->lock -> chan->lock -> sk_lock (lockdep).
KASAN/SMP: an unprivileged listen/close vs HCI-disconnect race produced
12 use-after-free reports per run before this change; 0, and no lockdep
report, over 1600+ raced iterations after it on bluetooth/master.
Fixes: 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Cc: stable@vger.kernel.org
Reported-by: Siwei Zhang <oss@fourdim.xyz>
Reviewed-by: Siwei Zhang <oss@fourdim.xyz>
Signed-off-by: Safa Karakuş <safa.karakus@secunnix.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
MGMT_OP_ADD_EXT_ADV_DATA is registered as a variable-length command,
with MGMT_ADD_EXT_ADV_DATA_SIZE as the fixed header size. The handler
then uses cp->adv_data_len and cp->scan_rsp_len to validate and copy
cp->data, but it never checks that those bytes are part of the mgmt
command payload.
A short command can therefore make add_ext_adv_data() pass an
out-of-bounds pointer into tlv_data_is_valid(). If the bytes beyond
the command buffer are addressable, they can also be copied into the
advertising instance as scan response data, where the caller can read
them back via MGMT_OP_GET_ADV_INSTANCE. The trigger requires
CAP_NET_ADMIN in the initial user namespace; KASAN reports an 8-byte
slab-out-of-bounds read.
Reject commands whose length does not match the fixed header plus both
advertising data lengths before parsing cp->data.
Fixes: 1241057283 ("Bluetooth: Break add adv into two mgmt commands")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
ISO data PDUs carry a packet-boundary flag indicating START, CONT, END
or SINGLE. The ISO_CONT branch of iso_recv() guards against a missing
ISO_START by checking conn->rx_len before touching conn->rx_skb, but
ISO_END does not.
If a peer sends an ISO_END as the first packet on a fresh ISO
connection, conn->rx_skb is still NULL and conn->rx_len is zero, so
skb_put(conn->rx_skb, ...) dereferences NULL and oopses. For BIS,
where receivers sync to a broadcaster without pairing, any broadcaster
on the air can trigger this.
Mirror the ISO_CONT check at the top of ISO_END so a stray end fragment
is logged and dropped instead of crashing the host.
Fixes: ccf74f2390 ("Bluetooth: Add BTPROTO_ISO socket type")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This fixes not setting the bit for HCI_EVT_LE_ALL_REMOTE_FEATURES_COMPLETE
when extended features bit is set otherwise the controller may not
generate HCI_EVT_LE_ALL_REMOTE_FEATURES_COMPLETE causing
hci_le_read_all_remote_features_sync to timeout waiting for it.
Also remove dead code.
Fixes: a106e50be7 ("Bluetooth: HCI: Add support for LL Extended Feature Set")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
bnep_add_connection() needs to keep holding the bnep_session_sem while
reading dev->name (just like bnep_get_connlist() does); otherwise the
bnep_session() thread can concurrently free the net_device, which can for
example be triggered by a concurrent bnep_del_connection().
(This UAF is fairly uninteresting from a security perspective;
calling bnep_add_connection() requires passing a capable(CAP_NET_ADMIN)
check. It also requires completely tearing down a netdev during a fairly
tight race window.)
Cc: stable@vger.kernel.org
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
cfg80211_wext_siwfreq() constructs a channel definition for monitor
mode but passes it to cfg80211_set_monitor_channel() without first
validating it with cfg80211_chandef_valid(). This causes a WARN_ON
in cfg80211_chandef_dfs_required() when it receives an invalid chandef.
Add the missing cfg80211_chandef_valid() check before calling
cfg80211_set_monitor_channel() to return -EINVAL early on invalid
channel definitions, consistent with how other callers handle this.
Reported-by: syzbot+02a1a03b8622d3c7d1c9@syzkaller.appspotmail.com
Signed-off-by: Kartik Nair <contact.kartikn@gmail.com>
Link: https://patch.msgid.link/20260510202437.7857-1-contact.kartikn@gmail.com
[clarify subject]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
ieee80211_tid_to_link_map_size_ok() validates negotiated TTLM elements
against the number of link-map entries indicated by link_map_presence.
ieee80211_parse_neg_ttlm() must consume the same layout.
The parser advanced its cursor for every TID, including TIDs whose
presence bit is clear and therefore have no map bytes in the element.
A sparse map can then make a later present TID read past the validated
element.
The bad bytes land in neg_ttlm->{up,down}link[tid] but are gated by
valid_links before being applied to driver state, so a peer cannot
turn the read into a policy change. Under KUnit + KASAN with an
exact-sized element allocation the OOB read is reported as a
slab-out-of-bounds; whether the same trigger fires under the
production RX path depends on surrounding allocator state.
Advance the cursor only when the current TID has a map present.
Fixes: 8f500fbc6c ("wifi: mac80211: process and save negotiated TID to Link mapping request")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260515151719.1317659-2-michael.bommarito@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
ieee80211_invoke_fast_rx() reads RX status through
IEEE80211_SKB_RXCB(skb), which aliases the same skb->cb storage
that ieee80211_rx_mesh_data() reuses as IEEE80211_TX_INFO. In the
unicast forward path, mesh_data does:
info = IEEE80211_SKB_CB(fwd_skb);
memset(info, 0, sizeof(*info));
on the same skb the caller still names via rx->skb, then either
queues the skb for TX (success) or kfree_skb()'s it (no-route)
before returning RX_QUEUED. The caller's RX_QUEUED arm then
calls sta_stats_encode_rate(status) on memory that is either
zeroed (success path) or freed (no-route path). The latter is
KASAN slab-use-after-free in ieee80211_prepare_and_rx_handle.
Fix by encoding the rate from status before invoking
ieee80211_rx_mesh_data(), so the RX_QUEUED arm consumes a value
captured while status was still backed by valid memory.
Fixes: 3468e1e0c6 ("wifi: mac80211: add mesh fast-rx support")
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Li <enderaoelyther@gmail.com>
Link: https://patch.msgid.link/20260509043427.60322-2-enderaoelyther@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When parsing a beacon, mac80211 erroneously inherits any
reconfiguration or EPCS multi-link elements from the outer
elements into the multi-BSSID profile that's requested, if
connected to a non-transmitted BSS, unless that profile
has a non-inheritance element.
This also happens if parsing a multi-BSSID profile that
doesn't have a non-inheritance element.
Fix this by having an empty non-inheritance element so
cfg80211_is_element_inherited() is invoked in these cases
and causes the parser to skip the elements that should
never be inherited.
Fixes: cf36cdef10 ("wifi: mac80211: Add support for parsing Reconfiguration Multi Link element")
Fixes: 24711d60f8 ("wifi: mac80211: Support parsing EPCS ML element")
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20260508091032.92184c0a3f08.I3c43b0b63d2cef8a4ddddaef1c2faaeb1de711ad@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If either reconf or EPCS multi-link element (MLE) is contained in
a non-transmitted profile, the defragmentation routine is called
with a pointer to the defragmented copy, but the original elements.
This is incorrect for two reasons:
- if the original defragmentation was needed, it will not find the
correct data
- if the original frame is at a higher address, the parsing will
potentially overrun the heap data (though given the layout of
the buffers, only into the new defragmentation buffer, and then
it has to stop and fail once that's filled with copied data.
Fix it by tracking the container along with the pointer and in
doing so also unify the two almost identical defragmentation
routines.
Fixes: 4d70e9c548 ("wifi: mac80211: defragment reconfiguration MLE when parsing")
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Link: https://patch.msgid.link/20260508091031.8a6c34613178.I4de16ebbce2d27f2f8f98fc49949c7a376c2fe8d@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
