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4365 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Jérémy Jean
|
7b16eb9110 |
net/sched: fix use-after-free in __tcf_action_put()
__tcf_action_put() decrements the reference count before decrementing the
binding count. Another thread can free the action between these operations,
causing the binding-count update to access freed memory. KASAN reports it
as:
BUG: KASAN: slab-use-after-free in __tcf_action_put+0x327/0x340
Write of size 4 at addr ff11000000d46420 by task tc-put-pause/64
Hold the action IDR mutex across both counter updates and IDR removal,
keeping cleanup outside the lock.
Fixes:
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Victor Nogueira
|
b72e025ac5 |
net/sched: cls_route: reject change with no routing attribute
route4_change on a filter change that supplies no routing attribute at all (no to/from/iif) reaches route4_set_parms with fold set, so the handle-mismatch check -- which only fires when creating -- is skipped. nhandle is built as the all-wildcard bucket (0x8000 | 0xFFFF << 16) and the filter is rekeyed to 0xFFFF8000, so the handle userspace already stored no longer addresses the filter. (The netlink reply carries the new handle; what goes stale is the handle the caller holds.) The rekey actually misclassifies the packets. The new handle's from_hash is the wildcard chain (route4_hash_wild), whose filters route4_classify applies without any id/iif comparison, and its bucket (256) is reached by every packet through the h < 256 restart. A filter that matched only a specific realm therefore becomes an unconditional catch-all that applies its classid and actions to all otherwise-unmatched traffic. Reject a change that would rekey the filter this way, with the routing-attributes-required error. A change that names at least one of to/from/iif, and an in-place replace that keeps the routing identity via a supplied attribute, are unaffected. A change of a filter that already sits at the wildcard handle is a metadata-only update and remains valid, so only a change that actually moves the handle is rejected. This is a follow-up to commit |
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Jamal Hadi Salim
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c9728fcf2e |
net/sched: em_text: reject unterminated algo before autoload
This is a follow-up to commit |
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Paolo Abeni
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e23a64eb24 |
netfilter pull request 26-09-30
-----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEjF9xRqF1emXiQiqU1w0aZmrPKyEFAmq8vB8ACgkQ1w0aZmrP KyFFVRAAodpV3MdxxjHIk4FOU6IY7e4PGx4HCqbRtEE9/WKDFKjUCpGxJuTNwuKS HIdU9W0ypdwyuNKTBhWcgbCqg9GbbZkmwJM3wBbsjPtBMJ13TcI0SYoJNp+MUCNu WlcrJrsdfkwMD3rNilx8iuCKrFcLx/l8qe6JWZNdP0lRu9dhkxEiqXgkKP+XB4CI mlV3TnP6MkG25GI9QmtKEtbIYrH4688bxO3LemzoVLm2vOvvrMG7cwqGr2XU7fYB IH8VocIVdzp6/w8JAxLbJNGR0bwGjdqJorz3ysmQ8jQPOt19PyP4WLmCbNuAoGMm XdLZPlDMqdoEe+KQhjlb7isPedoun7koNiOtqBQhjRvcCv03MH7LTmMgmV702+ex Hfm6EuaWINHeVGxNDADWebUyLy7jx3xYPqEpMA+UhgnbIicVGTJGGYiq5dGvObZE ek68iqmaoMRNay94sReakOtvHVz8iaXUhO60xdF0efrsDRnr7Yv6Ztxdl9nPCRIW fUz1/l7Z4j3gfTbmO1CKDK8aHlnibseYpQygLo53nkKWPcexJzYHbVl2tnjYUDZ6 dryGhLokthdAZW4W7hONvwlU+zT/eKfa4IesxgDglwGC9Hjxtwq2kuPrIuehMH/0 oEdVw6x4L+SBIrhnM9PaBBgp/dQarXZJQss3XfUxzmMPViScSxg= =cSG8 -----END PGP SIGNATURE----- Merge tag 'nf-26-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net The following batch contains Netfilter fixes for net. This batch fixes crashes as recent feature regression, one of the due to a dependency that has been pulled into -stable: 1) Expand existing ipset fix for bitmap sets to disallow comments updates from kernel-side adds, from Florian Westphal. 2) Drop flowtable reference if nf_ct_netns_get() fails, otherwise flowtable cannot ever be removed, from Aohan Mei. 3) nft_rbtree GC should collect end elements that contained in this transaction batch, new or deleted elements are never expired. From Weiming Shi. 4) Restrict nf_nat_bpf so it does not set unknown NF_NAT_MANIP_* values, from Fernando F. Mancera. 5) Flowtable GC must skip flows that are pending hardware updates, generalize the PENDING flag and use it to inhibit GC. 6) Restore flowtable with ieee80211 which broke due to a relatively recent commit, which was pulled in by -stable, causing a regression in 6.18 kernels. And the following IPVS fixes: 1) Fix accounting of cache entries in IPVS LBLC for destinations, which eventually fills up the table and trigger recurrent resizing, from Julian Anastasov. 2) Limit IPVS cache growth for LBLCR and LBLC schedulers, from Zhiling Zou. 3) Restrict IP_VS_CONN_F_ONE_PACKET for normal connections, do not allow to use it with templates. Also from Julian. 4) Sanitize flags in IPVS sync messages received in the backup. From Julian Anastasov. netfilter pull request 26-09-30 * tag 'nf-26-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: flowtable: restore ieee80211 forward path netfilter: flowtable: generalize pending status bit netfilter: bpf: reject invalid NAT manipulation types netfilter: nft_set_rbtree: skip transaction elements during GC ipvs: filter some flags received in the backup server ipvs: do not create invisible templates ipvs: bound LBLCR and LBLC cache growth ipvs: fix missing counter decrement in lblc netfilter: nft_flow_offload: drop flowtable reference on init error path netfilter: ipset: do not update comments from kernel-side adds ==================== Link: https://patch.msgid.link/20260930074142.298353-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
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Pablo Neira Ayuso
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7c549fb7ee |
netfilter: flowtable: generalize pending status bit
Rename NF_FLOW_HW_PENDING to NF_FLOW_PENDING and use it to inhibit the flowtable GC worker until pending hw offload work has been completed. Apparently, nf_flow_offload_stats() can schedule work to retrieve stats while the flow is being removed by GC. And this bit can also be used in a follow up patch to disable GC until the flow has been fully added in both directions. Revert the reordering done in commit |
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Jamal Hadi Salim
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ea4d4b5ddd |
net: cap skb->queue_mapping when the tx queue is picked
skbedit can set skb->queue_mapping and raise the per-CPU skip_txqueue flag so __dev_queue_xmit() honours the mapping. __dev_queue_xmit() cleared the flag before sch_handle_egress() and only read it afterwards, so the flag was not confined to the xmit that set it: a nested xmit (mirred redirect or mirror, or a drop after skbedit) could set the flag and the outer xmit would consume it for an skb that never went through skbedit. A forwarded packet still carries the ingress NIC's rx_queue + 1 in skb->queue_mapping, so the outer device then indexes its tx queue state with that stale value. Taprio's child array q->qdiscs[] is sized to the device's queue count, so taprio_enqueue() indexes past its allocation and dereferences the result as a struct Qdisc *. We (ab)use the skb->nf_skip_egress which means "skip netfilter egress for this packet" to tag to "am I in tc egress?". Despite the overload I dont see it as a conflict since the marker is set only around the single sch_handle_egress() call and ingress path is guarded by tc_at_ingress. I will send a followup(net-next) patch once this hits net-next to rename the skb->nf_skip_egress bit/flag to skb->skip_egress Arm the flag only from the egress classifier that can use it: raise skip_txqueue from tcf_skbedit_act() only when it runs inside sch_handle_egress(), thanks to skb->nf_skip_egress. An egress qdisc classifier runs in q->enqueue(), after the tx queue has been picked, so a mapping it sets cannot affect the current packet; arming the flag there only pollutes it for a later xmit. Then own the flag for the xmit frame the egress hook runs in: save the incoming value and clear it just before sch_handle_egress(), and restore it after the hook - on the consumed (drop) path, or, in the same call that reads it, on the surviving path. The save and the restores stay inside the egress_needed_key static branch, so a packet pays for them only when egress hooks are active ( |
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Jamal Hadi Salim
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54518e0e82 |
net/sched: sch_codel: match the no-drop threshold to the packet size
commit |
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Jamal Hadi Salim
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d031465acc |
net/sched: fq_codel: match the no-drop threshold to the packet size
commit |
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Jamal Hadi Salim
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0bb8eab29b |
net/sched: cls_api: reclaim an empty proto on the error path
Two racing tc filter add requests on the same chain/prio of an unlocked classifier both run change() on the shared proto and both can fail: the winner's tcf_chain_tp_delete_empty() attempt gives up because the loser's handle is still in the idr, and the loser's error path drops only its own reference without a second reclamation attempt. The empty proto stays linked in the chain, holding the chain reference, a block reference and the classifier module reference until the chain or block is torn down. Reclaim the proto on the error path of any failed request that holds a proto reference. The reclamation is emptiness-gated: tcf_chain_tp_delete_empty() unlinks the proto only when delete_empty() admits it is empty, so a live shared proto is never unlinked. A proto the request created is reclaimed unconditionally - it is the only owner, so marking it for deletion is safe even without a delete_empty callback. Classifiers without one (the check marks the proto unconditionally) are rtnl-serialized, so the raced window this guard closes cannot arise for them. This is a follow-up to commit |
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Eric Dumazet
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907b978e82 |
net/sched: sch_teql: fix shadowed err in __teql_resolve()
__teql_resolve() declares an inner 'int err;' inside the
'if (neigh_event_send(n, skb_res) == 0)' block, shadowing the outer
'int err = 0;'. As a result, a negative return from dev_hard_header()
is written to the inner variable and __teql_resolve() still returns 0.
Remove the shadowed variable and set the outer err to -EINVAL when
dev_hard_header() returns a negative error.
Fixes:
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Ilya Maximets
|
dad19b59da |
net/sched: act_ct: fix helper UAF due to extensions realloc
While calling the helpers, a raw pointer to the extensions area is
wired into expectations list:
-> nf_ct_helper()
-> helper->help()
-> nf_ct_expect_related_report()
-> nf_ct_expect_insert()
-> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)
In case the connection is not confirmed yet, more extensions can be
added afterwards with *_ext_add() calls reallocating the extension
space and leaving the now invalid pointer in the expectations list
that is later accessed while removing the expectation.
Make sure that helpers are called at the end after all the other
extensions are already added.
Note that the helper rejection now leaves the mark and labels set,
but that's not different from how the NAT was handled before or how
the mark and the labels were handled on confirmation failure. And
there are no atomicity guarantees provided by the API anyway.
Fixes:
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Ilya Maximets
|
00df72e39f |
net/sched: act_ct: remove 'add_helper' dead code
This variable can only become 'true' when the connection is not
confirmed, but it is only checked when it is confirmed. So, it can be
treated as being always false and just removed.
Fixes:
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Ilya Maximets
|
f85009dfcd |
net/sched: act_ct: avoid modifying shared unconfirmed ct entry
In a case where skb with an unconfirmed ct entry gets cloned, we may
end up processing both again but with different sets of extensions.
The series of events:
1. The first clone wants to commit and runs the helpers wiring up
the extension pointer into the expectation list.
2. Then it looses the confirmation keeping the entry unconfirmed.
3. Second clone now wants to commit labels or run NAT and adds the
new extension for that breaking the pointer in the expectation
list causing UAF on the destruction path later.
While this is possible to trigger, there should be no practical
network pipeline where we need to process both clones without
modifications in the same zone. So, let's just reset the entry in
case for some reason we got an skb with a shared one. This doesn't
affect any known use cases, but avoids any potential problems with
sharing and modification of the unconfirmed ct entry.
Unlike openvswitch module, act_ct allows for NAT without commit.
Changing that would be a uAPI break. So, act_ct needs to reset on NAT
regardless of the commit flag to avoid reallocation of the extension
space. This, however, doesn't really change the picture for sensible
networking cases as there should be no need to run the same packet
twice (before and after the clone) through conntrack without packet
header or zone changes and without commit.
The fixes tag points to the introduction of helpers, since that's the
main UAF trigger for the sharing.
Fixes:
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Fang Xieyan
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d6ec384c87 |
net/sched: act_ife: validate metadata length before decoding
skbmark_decode(), skbprio_decode() and skbtcindex_decode() read fixed-size values from the TLV payload without validating its length. A malformed IFE frame can declare a shorter payload, causing the decoders to consume bytes beyond the declared metadata value: [TLV type=IFE_META_SKBMARK len=4] -> dlen == 0, but decode reads 4 bytes The decoder may therefore set skb metadata from unintended input. Validate the payload length before decoding and return -EINVAL for invalid lengths. Read the values with get_unaligned_be32() and get_unaligned_be16(), as TLV payloads are not guaranteed to be aligned. Teach tcf_ife_decode() to log a decoder error separately from an unknown metaid; both are counted as overlimits and decoding continues with the remaining metadata. The metadata length issue was found by an automated audit of the IFE decode path at v6.18-rc7 and reproduced with a userspace sanitizer model of the decode path. Compile-tested on x86_64 with defconfig and NET_ACT_IFE=y: act_ife.o and the three act_meta_*.o build warning-free. Fixes: |
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Victor Nogueira
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cfa165cbfb |
net/sched: act_gate: budget the per-entry list in get_fill_size
tcf_gate_get_fill_size returns only the TCA_GATE_PARMS size, but
tcf_gate_dump also emits three 64-bit timestamps, the clock id, flags,
priority and the variable-length TCA_GATE_ENTRY_LIST nest. The per-entry
nest is unbounded: parse_gate_list places no cap on the number of
sched-entries, so a gate with many entries can push the real dump well
past the skb that tca_get_fill allocates from this size.
RTM_NEWACTION then fails the add-notify with -EINVAL while the action is
already committed to the IDR, and a subsequent RTM_GETACTION on the
installed gate also returns -EINVAL because its dump no longer fits.
Fix this by accounting for the missing fields in tcf_gate_get_fill_size
along with all elements in the entries list.
Note that sizing the reply from the action lets an oversized gate
install cleanly for the first time: with the input unbounded by
parse_gate_list, the sized skb can now grow well above
NLMSG_GOODSIZE per netlink request (a transient GFP_KERNEL allocation
reachable only with namespace-local CAP_NET_ADMIN). Overload from a
malicious netns admin is hardening material, not net, per the
discussion at
https://lore.kernel.org/netdev/20260914191108.55a1a4f1@kernel.org/;
a follow-up patch for net-next will cap the sched-entry count.
Fixes:
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Bernard Ladenthin
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9c572a8303 |
net/sched: fix potential stack infoleak in em_text_dump()
em_text_dump() allocates struct tcf_em_text on the stack without zeroing
it. strscpy() writes the algorithm name and a NUL terminator into
conf.algo[], leaving the remaining bytes uninitialised. nla_put_nohdr()
then copies the full struct to the netlink response.
KMSAN on Linux 7.2-rc6 reports two kernel-infoleak splats from this path,
one triggered via "tc filter show" and one via a raw RTM_GETTFILTER dump:
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x1c9/0x2620
nla_put_nohdr+0x83/0x130
em_text_dump+0x291/0x550
Local variable conf created at: em_text_dump+0x5d/0x550
Bytes 168-179 of 199 are uninitialized
I am not certain whether this constitutes a real security problem in
practice: the test was conducted in a controlled KMSAN environment and
the leaked stack bytes may or may not carry sensitive data on actual
production kernels. I am reporting it because KMSAN flagged it as a
kernel-infoleak and the fix is straightforward. I can provide a
userspace reproducer on request.
The original code used strncpy() which zero-pads to the destination size.
Commit
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Jamal Hadi Salim
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8a60ade227 |
net/sched: sch_hfsc: bound the classify inner-filter walk with a drift budget
hfsc_classify() applies the "filter may only point downwards" level check only when the filter result carries no bound class. A filter created with a flowid gets res.class set once at bind time, so the check never runs for it during classification. hfsc_adjust_levels() can later raise a class's level without revalidating existing bindings, leaving two binds that were each legal at bind time pointing at each other; the classify walk then bounces between two interior classes forever with the qdisc lock held and BH disabled — a soft lockup from a single packet. The stuck walk trips the watchdog: watchdog: BUG: soft lockup - CPU#3 stuck for 13s! [ping:444] RIP: 0010:u32_classify+0x542/0x17f0 ... tcf_classify+0x66/0xa0 hfsc_enqueue+0x166/0xdf0 Bound the traversal with a budget of non-descending hops, the only way a configured walk can move without descending the class tree once levels drift after bind time. The budget is cumulative over the whole walk and is deliberately not reset on a descending hop: a chain that alternates a descent with a lateral hop would return the budget every lap and never trip. Descending hops never decrement it, so legitimately deep trees are unaffected and a terminating lateral chain still classifies normally. Drop the packet with a rate-limited warning once the budget is exhausted, mirroring the merged HTB fix. This is a follow-up to commit |
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Weiming Shi
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c82b797abe |
net/sched: reject IDR error pointers when deleting actions
tcf_action_delete() drops the reference held by its lookup before calling
tcf_idr_delete_index() with the saved action index. An unlocked
classifier can remove that action and reserve the same IDR slot with
ERR_PTR(-EBUSY) in between.
tcf_idr_delete_index() only checks the lookup result for NULL. It
therefore treats the reservation as a tc_action and dereferences
tcfa_bindcnt. A hardware execution breakpoint was used to schedule the
interleaving without changing the kernel source. KASAN reported this
decoded trace:
BUG: KASAN: null-ptr-deref in tca_action_gd+0x5b9/0x1010
Read of size 4 at addr 0000000000000010 by task poc/150
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002
RIP: tca_action_gd+0x5c0/0x1010:
arch_atomic_read at arch/x86/include/asm/atomic.h:23
raw_atomic_read at include/linux/atomic/atomic-arch-fallback.h:457
atomic_read at include/linux/atomic/atomic-instrumented.h:33
tcf_idr_delete_index at net/sched/act_api.c:766
tcf_action_delete at net/sched/act_api.c:1859
tcf_del_notify at net/sched/act_api.c:2014
tca_action_gd at net/sched/act_api.c:2064
R13: 0000000000000010 R15: fffffffffffffff0
Kernel panic - not syncing: Fatal exception
R15 contains ERR_PTR(-EBUSY), and adding the tcfa_bindcnt offset produces
the address in R13. With the guard applied, the same reproducer returned
-ENOENT without a KASAN report or panic. Treat error pointers as absent
and return -ENOENT.
Fixes:
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Nguyen Ngoc Thang
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47abe7a5c4 |
net/sched: act_ct: don't WARN on benign flow_offload_alloc() failure
flow_offload_alloc() returns NULL when the conntrack entry is dying
(e.g. raced with a conntrack flush) or when the GFP_ATOMIC allocation
fails; both are expected under load and neither is a kernel bug. This
path runs from softirq on every committed packet, so with
panic_on_warn=1 an unprivileged user can panic the box just by racing
a conntrack flush against a `tc ... action ct commit` classifier.
Reproduced with a custom repro under QEMU: a small, fixed set of UDP
flows through `tc filter ... action ct commit` on lo, raced against
threads flooding bare ctnetlink CT_DELETE (flush) requests. Hits
WARNING: net/sched/act_ct.c:437 (tcf_ct_flow_table_add(), inlined
into tcf_ct_act() in this build) within ~15s on the unpatched kernel;
same setup is clean on the patched kernel. The fix itself is
behavior-preserving: both branches already did `goto err_alloc`
before and after, only the WARN is removed.
Fixes:
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Jamal Hadi Salim
|
0a5f5d9e94 |
net/sched: cls_u32: fix manual hash table handle IDR aliasing
A u32 hash table created with an explicit handle ('tc filter add ...
handle 801: u32 divisor N') keys its IDR entry on the raw handle, while
the destroy paths free it under handle2id(handle). The two key domains
disagree for handles in the 0x800..0xFFF htid range:
handle2id() folds them back into the auto-allocated id space (1..0x7FF).
A manual table therefore leaves its raw-keyed IDR entry unreachable on
delete (a permanent leak), and its delete can drop the idr entry of an
unrelated live auto table. A later auto allocation can then hand out a
handle that aliases the live manual table; u32_lookup_ht() first-match
routes lookups and TCA_U32_LINK for that htid to the wrong table.
Key the divisor-path alloc on handle2id(handle) so allocation and
removal share one key domain. A manual handle that maps onto an id
already in use is rejected with -ENOSPC, and auto allocation skips ids
held by live manual tables.
Conditions to recreate:
ip link add test0 type dummy
tc qdisc add dev test0 clsact
tc filter add dev test0 ingress protocol ip pref 1 \
handle 801: u32 divisor 16
tc filter add dev test0 ingress protocol ip pref 2 u32 divisor 16
tc -d filter show dev test0 ingress | grep 'fh 801:'
# unpatched: two live tables with handle 0x80100000 (the pref 2 root
# hnode is auto-allocated id 1); patched: the auto hnode takes id 2.
Also tested with a poc with a live u32 table on the block, add/delete a manual
table 'handle 901: u32 divisor 1' twice; unpatched, the re-add fails with
-ENOSPC because the raw key leaked on the first delete.
Fixes:
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Xuanqiang Luo
|
6e05e46fa8 |
net/sched: act_api: release tail references on DELACTION failure
A batched RTM_DELACTION request takes a temporary reference on each
action before attempting any deletion. tcf_action_delete() clears
each processed slot and drops its temporary reference before attempting
the deletion. If deletion fails, tca_action_gd() calls
tcf_action_put_many() to release the remaining references, but its
tcf_act_for_each_action() iterator stops at the first NULL slot.
When a batch stops at an action bound to a filter, this leaks a
reference on each subsequent action. A later delete of an unbound
action can then return success without removing it from the IDR.
Walk the full array in tcf_action_put_many() and skip NULL slots to
release the references held on the unprocessed actions.
Fixes:
|
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Jamal Hadi Salim
|
2cef2588c9 |
net/sched: hhf: cap hh_flows_limit at change time
hhf_change() stores TCA_HHF_HH_FLOWS_LIMIT with no upper bound. A huge hh_flows_limit lets each new heavy-hitter flow pass the hh_flows_current_cnt check in alloc_new_hh() and forces a fixed-size kzalloc(GFP_ATOMIC) per flow under spoofed traffic, for unbounded memory growth. Bound the attribute with NLA_POLICY_MAX() at 2*HH_FLOWS_CNT (the hhf_init() default) and report the rejected value via extack. The deprecated nested parse is kept: legacy tc does not set NLA_F_NESTED on TCA_OPTIONS. Configs relying on hh_limit above the default were relying on unbounded, unsafe behaviour and are not supported going forward. hhf_init() also ran hhf_change() before setting the default hh_flows_limit, so a user-supplied hh_limit at add time was clobbered back to 2048. Set the default before hhf_change() so the configured value sticks. This is a follow-up to commit |
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Linus Torvalds
|
7844502343 |
Nothing too exciting, usual stream of fixes.
Including fixes from Netfilter, Bluetooth and WPAN.
Current release - new code bugs:
- Bluetooth: hci_sync: fix not setting CE length properly
- eth: enic: match mailbox replies to request numbers
Previous releases - regressions:
- tunnels: drop stale dst when building an ICMP error for PMTUD
- ipv6: null-check fib6_node before accessing in __ip6_del_rt_siblings()
(bug in the rtnl_lock -> RCU conversion)
- eth: bnxt_en: fix crashes on Thor2 due to OOB coalescing buffer accesses
- eth: bnxt_en: prevent queue stop with deferred completions
Previous releases - always broken:
- eth: ice: don't dereference pointers from TP_printk()
- eth: fix OOB writes on ethtool flow rule dump in 3 drivers
- eth: mlx5: fix FEC configuration with RS_544_514_INTERLEAVED_QUAD
- dsa: tag_brcm: legacy FCS: request needed tailroom
Misc:
- net: cap tx_queue_len at S16_MAX to prevent oversized ring alloc
- ipv6: flowlabel: cap duplicate leases per socket
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Nothing too exciting, usual stream of fixes. Including fixes from
Netfilter, Bluetooth and WPAN.
Current release - new code bugs:
- Bluetooth: hci_sync: fix not setting CE length properly
- eth: enic: match mailbox replies to request numbers
Previous releases - regressions:
- tunnels: drop stale dst when building an ICMP error for PMTUD
- ipv6: null-check fib6_node before accessing in __ip6_del_rt_siblings()
(bug in the rtnl_lock -> RCU conversion)
- eth: bnxt_en:
- fix crashes on Thor2 due to OOB coalescing buffer accesses
- prevent queue stop with deferred completions
Previous releases - always broken:
- eth:
- ice: don't dereference pointers from TP_printk()
- fix OOB writes on ethtool flow rule dump in 3 drivers
- mlx5: fix FEC configuration with RS_544_514_INTERLEAVED_QUAD
- dsa: tag_brcm: legacy FCS: request needed tailroom
Misc:
- net: cap tx_queue_len at S16_MAX to prevent oversized ring alloc
- ipv6: flowlabel: cap duplicate leases per socket"
* tag 'net-7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (164 commits)
selftests: tc-testing: test action batch failure cleanup
net/sched: act_api: release all action references on NEWACTION failure
openvswitch: fix wrong flag value in get_ipv6_ext_hdrs()
ipmr: account multicast table and route memory
net: phy: dp83td510: handle the active-high LED polarity mode
net: macb: initialize PTP state before registering clock
net: hsr: enable promiscuous mode on interlink port with fwd offload
ipv6: fix fib6 walker UAF on seq stop
net: stmmac: fix TX descriptor availability check for TSO traffic
net/rds: fix tcp stream corruption with large pages
net: mana: restore the XDP program pointer when pre-allocation fails
net: phy: dp83867: handle the active-high LED polarity mode
octeontx2-af: fix PF/CGX debugfs PCI bus lookup
net: net_failover: Fix the deadlock in net_failover_slave_name_change()
net: phy: mediatek-ge: disable EEE on the MT7530 PHY
tcp: reject non zerocopy devmem tx
net: ethernet: mtk_eth_soc: populate lpi_interfaces to fix EEE support
net: dsa: mt7530: populate lpi_interfaces to fix EEE support
net: hinic: fix mailbox segment buffer overflow
net: sun4i-emac: fix missing of_node_put() for phy_node
...
|
||
|
Xuanqiang Luo
|
478eb5abb5 |
net/sched: act_api: release all action references on NEWACTION failure
When a batched RTM_NEWACTION request replaces an existing action,
tcf_idr_check_alloc() takes a temporary reference on it. If a later
action fails to initialize, tcf_action_destroy() uses strict release
semantics to clean up the actions initialized so far. For an action
bound to a filter, the strict check returns -EPERM without dropping
the temporary reference.
This error also makes tcf_action_destroy() return before releasing
subsequent entries. Any new action initialized between the bound
action and the failing entry is leaked together with its reserved
IDR slot, preventing reuse of its index.
Use tcf_idr_release() to drop each reference held by the batch without
rejecting bound actions. This allows cleanup to continue through all
initialized entries and preserves the module reference release when
an action is destroyed. Explicit action deletion and flushing retain
their separate bind-count checks.
Fixes:
|
||
|
Kuniyuki Iwashima
|
dff39930ad |
net/sched: cls_api: Don't replay RTM_GETCHAIN in tc_ctl_chain().
If a netlink socket sends RTM_GETCHAIN requests repeatedly without recv()ing the responses, tc_ctl_chain() hogs CPU and triggers Hung Task splat. [0] As caught in the stack trace, netlink_attachskb() could confuse tc_ctl_chain() by returning -EAGAIN when the userspace netlink socket's receive buffer is full. The replay: label exists since commit |
||
|
Victor Nogueira
|
41e85e54e5 |
net/sched: cls_route: Fix in-place replace
Building on the previous patch, route4_set_parms rejects a duplicate by
scanning the destination chain for nhandle, but the scan doesn't exclude
the older version it is replacing, so an in-place replace will match
the older version's handle and fail.
Fix this by passing the older filter as a parameter to route4_set_parms
(replacing "new") and skipping it in the scan.
Excluding the older version is not enough on its own. nhandle is built
out of TCA_ROUTE4_TO, TCA_ROUTE4_FROM and TCA_ROUTE4_IIF alone, while the
0x7F00 bits, which only tell apart filters sharing one key, are folded in
on the create path. Letting the replace through would therefore rename
the filter it replaces: replacing handle 0x10101 stored it back as
0x10001, and a sibling at 0x10201 could then no longer be replaced at
all, since its own nhandle collided with the renamed filter.
tc filter add ... handle 0x10101 route from 1 to 1 classid 1:1
tc filter add ... handle 0x10201 route from 1 to 1 classid 1:2
tc filter replace ... handle 0x10101 route from 1 to 1 classid 1:9
... fh 0x00010001 flowid 1:9 to 1 from 1
... fh 0x00010201 flowid 1:2 to 1 from 1
tc filter replace ... handle 0x10201 route from 1 to 1 classid 1:8
Error: Handle 10001 is already in use.
So carry those bits over when the key the request builds is the key the
older filter already has. An in-place replace then keeps the handle
userspace named the filter by, while a request that does change the key
still renames it, as it did before.
Fixes:
|
||
|
Victor Nogueira
|
b74a8455a2 |
net/sched: cls_route: Reject handle aliasing
route4_set_parms() rejects a duplicate by scanning the destination chain
for f->handle, but f->handle is the handle the filter has before the
update, not the one it is about to be linked under. The comparison and
the insertion therefore use different handles, which causes breakage.
When a change moves the filter to a chain that already holds nhandle,
the scan looks for the old handle instead, misses the collision and
links a second filter with the same handle:
tc filter add dev lo ingress protocol ip pref 100 \
route from 1 to 1 classid 1:1 action ok
tc filter add dev lo ingress protocol ip pref 100 \
route from 2 to 2 classid 1:2 action drop
tc filter change dev lo ingress protocol ip pref 100 handle 0x10001 \
route from 2 to 2 classid 1:1 action ok
tc filter show dev lo ingress
... fh 0x00020002 flowid 1:2 to 2 from 2
... fh 0x00020002 flowid 1:1 to 2 from 2
The newcomer is appended after the incumbent, and both end up with the
same f->id. route4_get() returns the first match, so the second filter
can no longer be addressed by handle, and route4_classify() stops at the
first filter whose f->id matches. The second filter is dumped but is
effectively dead.
Fix this by comparing against nhandle.
Fixes:
|
||
|
Victor Nogueira
|
1853f30cf5 |
net/sched: cls_route: free emptied bucket on filter move
route4_change can move an existing filter to a different top-level
bucket: route4_set_parms recomputes the handle from TCA_ROUTE4_TO/
FROM/IIF, and the handle-mismatch check is gated on the 'new' flag, so
for an existing filter the new handle may differ from the old one and
land in a different bucket. When this happens, the filter is unlinked
from the old bucket, but the bucket itself is never freed once it goes
empty. The stale empty bucket remains in head->table[], causing
route4_delete to report *last=false even after the last live filter is
gone. That pins the empty tcf_proto and causes a leak.
Fix this by refcounting the filters linked to a bucket and freeing the
bucket when the count drops to zero. The existing scan in route4_delete
goes away with it.
The count is updated at all sites that link or unlink a filter during add,
change and delete, and the bucket is dropped from head->table[] as soon as
it reaches zero.
Conditions to recreate the bug:
CONFIG_NET_CLS_ROUTE4=y, CONFIG_NET_SCH_INGRESS=y, CONFIG_NET_CLS_ACT=y.
tc qdisc replace dev lo clsact
tc filter add dev lo ingress protocol ip pref 100 route from 1 to 1
tc filter change dev lo ingress protocol ip pref 100 handle 0x10001 \
route from 1 to 2
tc filter del dev lo ingress protocol ip pref 100 handle 0x10002 \
route from 1 to 2
tc filter show dev lo ingress | grep -c 'pref 100 route chain 0 '
Fixes:
|
||
|
Jamal Hadi Salim
|
1c38487f46 |
net/sched: ets: clamp quantum in parse and fallback paths
ets_qdisc_change() falls back to psched_mtu() with no floor for bands
without an explicit quantum. With a crafted size table qdisc_pkt_len
reaches ~2 GiB, so a zero psched_mtu on a headerless device makes the
deficit-refill loop spin under the qdisc lock.
Move the floor into ets_quantum_parse() so explicitly configured quanta
are also clamped to [256, 1<<20], not just the fallback path.
Conditions to recreate the bug:
CONFIG_NET_SCH_ETS=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root ets bands 3 strict 2 quanta 1 1
Fixes:
|
||
|
Jamal Hadi Salim
|
8382abec0f |
net/sched: drr: clamp quantum in change class
drr_change_class() rejects explicit quantum==0 but falls back to
psched_mtu() with no floor. With a crafted size table qdisc_pkt_len
reaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless
device) makes the deficit-refill loop spin under the qdisc lock.
Add clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the
fallback path. The explicit-zero reject is preserved.
Conditions to recreate the bug:
CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root drr
tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1
Fixes:
|
||
|
Jamal Hadi Salim
|
54370e44c0 |
net/sched: pie: clamp psched_mtu in pie_drop_early
pie_drop_early() calls psched_mtu() with no clamp. With mtu=0x80000000
the bytemode divide silently zeroes the drop probability, disabling AQM.
Clamp to [1, 1<<20].
Conditions to recreate the bug:
CONFIG_NET_SCH_PIE=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root pie
tc qdisc change dev dummy0 root pie stab data 32768 size_log 15 cell_log 0
Fixes:
|
||
|
Jamal Hadi Salim
|
3c01f1ca5d |
net/sched: dualpi2: clamp psched_mtu at all call sites
dualpi2_calculate_c_protection(), must_drop(), and get_memory_limit()
call psched_mtu() with no clamp. A huge MTU makes (s32)psched_mtu()
overflow in the signed multiply for c_protection_init, and 2 *
psched_mtu() wraps in get_memory_limit(). With a crafted size table
qdisc_pkt_len reaches ~2 GiB, causing a soft lockup / denial of service.
Clamp psched_mtu() to [1, 1<<20] at all three call sites.
Conditions to recreate the bug:
CONFIG_NET_SCH_DUALPI2=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root dualpi2
tc qdisc change dev dummy0 root dualpi2 stab data 32768 size_log 15 cell_log 0
Fixes:
|
||
|
Jamal Hadi Salim
|
eb56a495f5 |
net/sched: hhf: clamp quantum in change and init paths
hhf_change() accepts any quantum from userspace, including 1. With a
crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1 makes
the deficit-refill loop spin ~2^31 times under the qdisc lock
(a soft lockup / denial of service).
Add max(256U, ...) in hhf_change() matching fq_codel_change(). Clamp
hhf_init() to [256, 1<<20] matching the siblings, and remove the old
fallback that only set quantum=256 on overflow.
Conditions to recreate the bug:
CONFIG_NET_SCH_HHF=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root hhf
tc qdisc change dev dummy0 root hhf quantum 1 stab data 32768 size_log 15 cell_log 0
Fixes:
|
||
|
Jamal Hadi Salim
|
fb9f88a33c |
net/sched: sfq: clamp quantum in change path
sfq_change() accepts any non-negative quantum (only rejects
(int)ctl->quantum < 0). With a crafted size table qdisc_pkt_len reaches
~2 GiB, so quantum=1 makes the deficit-refill loop spin ~2^31 times
under the qdisc lock (a soft lockup / denial of service).
Add max(256U, ...) matching fq_codel_change(). Reject quantum > 1<<20
with -EINVAL, matching fq_codel_change() and the init clamp.
Conditions to recreate the bug:
CONFIG_NET_SCH_SFQ=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root sfq
tc qdisc change dev dummy0 root sfq quantum 1 stab data 32768 size_log 15 cell_log 0
Fixes:
|
||
|
Jamal Hadi Salim
|
4864f58c53 |
net/sched: fq_pie: clamp quantum in change path
fq_pie_change() accepts any quantum value from userspace, including 1.
With a crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1
makes the deficit-refill loop spin ~2^31 times under the qdisc lock
(a soft lockup / denial of service).
Add max(256U, ...) matching fq_codel_change().
Conditions to recreate the bug:
CONFIG_NET_SCH_FQ_PIE=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root fq_pie
tc qdisc change dev dummy0 root fq_pie quantum 1 stab data 32768 size_log 15 cell_log 0
Fixes:
|
||
|
Jamal Hadi Salim
|
094cc07f98 |
net/sched: fq: clamp quantum and initial_quantum in change path
The fq change path accepts TCA_FQ_QUANTUM in [1, INT_MAX] and
TCA_FQ_INITIAL_QUANTUM up to INT_MAX, while fq_init() already clamps to
[1, 1<<20]. A user can override the init clamp via tc qdisc change,
restoring the small-quantum deficit spin that the init clamp prevents.
Narrow iq_range.max to 1<<20 so TCA_FQ_INITIAL_QUANTUM is rejected at
parse time. Clamp TCA_FQ_QUANTUM to [256, 1<<20] in fq_change() and
fq_init() quantum to [256, 1<<20] for tiny-MTU devices.
Conditions to recreate the bug:
CONFIG_NET_SCH_FQ=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root fq
tc qdisc change dev dummy0 root fq quantum 1 stab data 32768 size_log 15 cell_log 0
Fixes:
|
||
|
Weiming Shi
|
e6662f2100 |
net/sched: defer qdisc freeing after failed creation
An RTM_NEWQDISC request can make clsact bind a populated shared ingress
block during ->init(), publishing an embedded mini_Qdisc to lockless
readers. If the same request has an invalid TCA_RATE, estimator setup
fails after ->init(); the unwind removes the pointer but synchronously
frees its containing qdisc while tc_run() may still hold it.
Retire failed qdiscs through the same RCU helper as normal destruction.
Inline the synchronous free into the callback now that no direct callers
remain.
Fixes:
|
||
|
Kees Cook
|
3a2c4d55e3 |
treewide: refresh kmalloc_obj() conversions
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org> |
||
|
Aohan Mei
|
fee1065570 |
net/sched: cls_flower: validate mask pointer after nla_next()
fl_set_enc_opt() iterates the key's nested tunnel-option attributes with nla_for_each_attr() while advancing a single mask pointer via nla_next() at the bottom of each loop, so the mask cursor is driven by the number of key attributes rather than by the mask's own attributes. The nla_ok() added by commit |
||
|
Jamal Hadi Salim
|
d7e7e98d23 |
net/sched: cls_u32: fix duplicate handle when node ID pool is exhausted
gen_new_kid() falls back to returning max (htid | 0xFFF) when both
idr_alloc_u32() ranges are full, instead of reporting an error.
u32_change() trusts that value and inserts a new knode with a handle
that is already live in the hash table, breaking handle uniqueness
within the table's node ID space.
The handle was never reserved in ht->handle_idr, so every later error
path that does idr_remove(&ht->handle_idr, handle) removes the
reservation of a different, live knode, which is then reused — one
failed add compounds into further duplicates.
The 4095 limit is per (table, bucket) — ht->handle_idr is per hash
table and the range is derived from htid (bucketid), so a table with
divisor 256 can legitimately hold 256*4095 knodes.
The sibling helper gen_new_htid() has the same silent in-band failure:
it returns 0 when the tp_c handle pool (1..0x7FF) is full, and
u32_init() publishes the root hash table with handle 0 without
checking. Two root tables with handle 0 alias in u32_lookup_ht(),
allowing cross-tcf_proto knode add/lookup/delete. Add the same
exhaustion check that the divisor path already has.
Return an error so u32_change() fails with ENOSPC/ENOMEM when the
node ID space is exhausted, and so u32_init() fails with -ENOMEM
when the hash table ID space is exhausted. The extack message
distinguishes pool exhaustion (-ENOSPC) from a transient allocation
failure (-ENOMEM).
Conditions to recreate the bug:
- CONFIG_NET_SCHED=y, CONFIG_CLS_U32=y (or =m with module loaded)
- Create a clsact qdisc on a device, then add 4095 u32 filters with
auto-generated handles to fill the node ID space for the root hash
table (single bucket). The 4096th auto-handle filter add triggers
the duplicate handle (fh 800::fff reused). Reachable at Level 2
(unshare -Urn, namespace-local CAP_NET_ADMIN).
- For gen_new_htid: create 2047 u32 proto entries on the same block
to fill the tp_c handle pool, then create one more. The root table
gets handle 0 and aliases with other handle-0 root tables.
Fixes:
|
||
|
Victor Nogueira
|
251367a0a3 |
net/sched: act_api: fix skb sizing and action leak on reoffload delete
tcf_reoffload_del_notify_msg() sizes the RTM_DELACTION skb with tcf_action_fill_size(action) alone. Unlike every other notification path it never wraps that in tcf_action_full_attrs_size(), so the nlmsg_put() header, struct tcamsg and the TCA_ACT_TAB nest that tca_get_fill() emits - 24 bytes on x86_64 - are not budgeted. As long as the single action stays well under NLMSG_GOODSIZE the floor in alloc_skb() hides this, but once its fill size crosses NLMSG_GOODSIZE the allocation is exactly 24 bytes short and tca_get_fill() runs out of tailroom. That is now easy to reach for an offloadable act_pedit with a large tcfp_nkeys, which commit |
||
|
Victor Nogueira
|
e9ca46ebc3 |
net/sched: act_api: size the RTM_GETACTION reply from the actions
tca_action_gd() already walks every requested action and accumulates
attr_size += tcf_action_fill_size(act), then wraps the result in
tcf_action_full_attrs_size(). For RTM_DELACTION that value is handed to
tcf_del_notify_msg(), which allocates max(attr_size, NLMSG_GOODSIZE). For
RTM_GETACTION it is silently discarded and tcf_get_notify() allocates a
fixed NLMSG_GOODSIZE skb instead.
Any action whose dump exceeds that fixed budget therefore cannot be read
back. For example, act_pedit overruns the budget with 32 actions of four
munge keys each, act_police with 32 policers once the optional
rate/peakrate/result/avrate attributes are present
Fix this by passing attr_size through and allocate the reply the way the
add and delete paths do.
Note on exposure: RTM_GETACTION is the only one of the three action
commands that is not capability checked - tc_ctl_action() requires
CAP_NET_ADMIN for RTM_NEWACTION and RTM_DELACTION only - so this turns a
fixed NLMSG_GOODSIZE reply into a user sized allocation on an
unprivileged path. It is bounded by TCA_ACT_MAX_PRIO actions per
request, and tca_action_gd() does not reject duplicate indices, so a
single large action can be requested 32 times; an act_bpf program near
BPF_MAXINSNS is about 32KB of dump, or roughly 1MB for one request.
Creating such an action still requires CAP_NET_ADMIN, and the add and
delete paths have sized their skbs this way since the Fixes commit.
Should this ever need bounding, GFP_KERNEL_ACCOUNT would charge the
reply to the caller's memcg.
Fixes:
|
||
|
Victor Nogueira
|
13eb543ceb |
net/sched: act_api: budget all shared attributes in notify skbs
tcf_action_shared_attrs_size() is supposed to return an upper bound on the
netlink attributes every action dump emits outside of TCA_ACT_OPTIONS, so
that tcf_add_notify_msg(), tcf_del_notify_msg() and friends can allocate
an skb large enough for the reply. It has fallen behind the dump path and
is now an underestimate for every single action.
Attributes, such as, TCA_ACT_IN_HW_COUNT and TCA_STATS_BASIC_HW are
emitted unconditionally and never accounted for. TCA_STATS_PKT64,
TCA_ACT_USED_HW_STATS, TCA_STATS_RATE_EST, TCA_STATS_RATE_EST64 require
specific conditions, but are also not accounted for.
Fix the issue by budgeting all of them so that we have a legitimate
upper bound. Even tough for of them require specific conditions, they
are cheap so, to avoid overcomplicating, we opted to account for them
unconditionally as well to account for a real worst case scenario.
Fixes:
|
||
|
Jamal Hadi Salim
|
729c4896ab |
net/sched: sch_htb: limit htb_classify inner-class filter hops
htb_classify() follows each filter-selected inner class by switching
to cl->filter_list, but never bounds the number of hops. A filter on
an inner class can point back to itself or to another inner class that
points back, creating an infinite loop in the packet classification
path with the qdisc lock held and BH disabled — a soft lockup / panic
from a single packet.
Bound the traversal with a hop counter and drop the packet with a
rate-limited warning once the bound is exceeded. The counter is
incremented at the point the inner filter chain is picked up, after the
TC_ACT_* switch has consumed the classifier verdict, so a terminal
TC_ACT_QUEUED/STOLEN/TRAP on the last permitted chain still sets *qerr
to __NET_XMIT_STOLEN and the packet is not charged as a drop by this
qdisc or its parent.
The bound is TC_HTB_MAXDEPTH, taken from HTB's own parameters rather than
from the qdisc hierarchy depth limit. Class levels run from 0 to
TC_HTB_MAXDEPTH - 1, so a traversal that strictly descends in level can
take at most TC_HTB_MAXDEPTH hops. That descent is what a sane
configuration does, but it is assumed here rather than enforced:
htb_find() resolves a classid against every class in the qdisc, so a
filter may equally select a sibling or an ancestor. The normal
root -> inner -> leaf path takes a single hop, so the bound does not
affect legitimate classification.
htb_classify() can now return NULL irrespective of CONFIG_NET_CLS_ACT,
whereas previously every NULL return sat inside that ifdef. The NULL
handler in htb_enqueue() therefore cannot stay conditional either, so
drop the ifdef around it. This matches hfsc_enqueue(), which has always
handled a NULL class unconditionally. Without it, a kernel built
without actions would dereference a NULL class instead of dropping.
Conditions to recreate the bug:
- CONFIG_NET_SCHED, CONFIG_NET_SCH_HTB, CONFIG_NET_CLS_U32,
CONFIG_LOCKUP_DETECTOR.
- Create an HTB qdisc on a device (e.g. lo), add an inner class
1:1 with a leaf child 1:10, install a root u32 filter selecting
1:1, and an inner-class u32 filter on 1:1 also selecting 1:1.
- Send one packet (ping). On the unfixed kernel the classify loop
spins with the qdisc lock held; with softlockup_panic=1 it panics.
- Reachable from unprivileged user via unshare -Urn (CAP_NET_ADMIN).
Fixes:
|
||
|
Jamal Hadi Salim
|
8f735d6438 |
net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup
qdisc_get_stab() accepts a user-supplied size table, and
__qdisc_calculate_pkt_len() amplifies qdisc_pkt_len() through the
overhead, the size-table data (u16), and size_log (up to
STAB_SIZE_LOG_MAX). A crafted stab can therefore set qdisc_pkt_len()
to ~1 GiB for an ordinary skb. Per-flow deficit schedulers such as
DRR and ETS replenish one quantum per loop iteration; with a tiny
quantum (1) they spin billions of times under the qdisc lock,
producing a soft lockup / RCU stall as illustrated by vega@nebusec.ai.
Cap the final qdisc_pkt_len() to QDISC_PKT_LEN_MAX so the size-table
amplification cannot drive deficit schedulers into an unbounded loop.
A legitimate size table (e.g. qfq's overhead 999999999, which is
handled by dropping) is still accepted.
Introduce cap QDISC_PKT_LEN_MAX (1 << 20) = 1 MiB which is well above
any legitimate single-skb wire length: the largest current skb->len
is GSO_MAX_SIZE (524280), and an ATM-style size table (53/48 cell tax)
amplifies that to ~578 KB, both comfortably below 1 MiB. At the same
time, 1 MiB bounds the deficit refill loop to ~1M iterations per
packet with quantum=1, which completes in a few milliseconds well
under the demonstrated softlockup threshold (~10^9 iterations).
Conditions to recreate the bug:
- CONFIG_NET_SCHED=y, CONFIG_NET_SCH_DRR=y (or CONFIG_NET_SCH_ETS=y).
- Attach a DRR (or ETS) root qdisc with a crafted TCA_STAB that
amplifies qdisc_pkt_len to ~1 GiB (e.g. size_log=15, data=[32768]).
- Add a class with a tiny quantum of 1 and send one small packet; the
deficit loop spins billions of times under the qdisc lock and trips
the softlockup detector (panic with kernel.softlockup_panic=1).
- Reachable as root or from an unprivileged user in a fresh user+net
namespace (unshare -Urn) with namespace-local CAP_NET_ADMIN.
Fixes:
|
||
|
Breno Leitao
|
82aeed2400 |
net: fix spurious TX timeout after dev_activate()
While debugging another issue today, I found out that my TX queue is
reported as stopped for 4294907392 ms (49.7 days), on a machine that
had been up for four minutes.
bnxt_en 0002:01:00.0 eth0: NETDEV WATCHDOG: CPU: 28: transmit queue 23 timed out 4294907392 ms
4294907392 is not an elapsed time. It is the value of jiffies at that
moment: INITIAL_JIFFIES is 4294667296, which leaves jiffies 59 seconds
short of wrapping.
dev_activate() runs transition_one_qdisc() over every TX queue, which
resets trans_start to 0, and then stamps only queue 0 through
netif_trans_update().
Stamp jiffies instead. A queue stopped across dev_activate() now gets a
full watchdog_timeo of grace, and is still reported if it is stopped
that long.
Fixes:
|
||
|
Victor Nogueira
|
dc4b95b8fe |
net/sched: sch_teql: restore skb->dev on the slave failure path
teql_master_xmit() sets skb->dev = slave before calling the slave's
ndo_start_xmit(), but never restores it when that transmit fails. The
skb then walks on to the next slave still pointing at the previous one.
If a later slave has no resolved neighbour, teql_resolve() hands the skb
to neigh_event_send(), which queues it on that neighbour's arp_queue
with the stale skb->dev. skb->dev holds no reference, so deleting the
previous slave frees the net_device while the skb is still queued.
Whatever runs next on that skb - arp_error_report() on timeout, or
neigh_direct_output() -> dev_queue_xmit() once the neighbour resolves -
causes a UAF like the one below:
BUG: KASAN: slab-use-after-free in __icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
Read of size 4 at addr ffff888106e100b0 by task flood_packet/527
CPU: 0 UID: 0 PID: 527 Comm: flood_packet Not tainted 7.2.0-rc6-g594d90519502 #1 PREEMPT(lazy)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
print_report (mm/kasan/report.c:378 mm/kasan/report.c:482)
? __pfx__raw_spin_lock_irqsave (./include/asm-generic/qrwlock.h:122 (discriminator 4))
? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
kasan_report (mm/kasan/report.c:595)
? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
__icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
[...]
ipv4_link_failure (net/ipv4/route.c:1251 net/ipv4/route.c:1258)
? __pfx_ipv4_link_failure (./include/linux/skbuff.h:4327)
? _raw_write_lock (./include/linux/instrumented.h:55 ./include/linux/atomic/atomic-instrumented.h:1301 ./include/asm-generic/qrwlock.h:98 ./include/linux/rwlock_api_smp.h:230 kernel/locking/spinlock.c:304)
? __pfx__raw_write_lock (kernel/locking/spinlock.c:175)
arp_error_report (./include/net/dst.h:438 net/ipv4/arp.c:296)
neigh_invalidate (net/core/neighbour.c:1077)
neigh_timer_handler (net/core/neighbour.c:1169)
[...]
Allocated by task 505:
kasan_save_stack (mm/kasan/common.c:57)
kasan_save_track (mm/kasan/common.c:78)
__kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)
__kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5334 mm/slub.c:6905)
alloc_netdev_mqs (net/core/dev.c:12055 (discriminator 2))
rtnl_create_link (net/core/rtnetlink.c:3721)
rtnl_newlink (net/core/rtnetlink.c:3903 net/core/rtnetlink.c:4044 net/core/rtnetlink.c:4159)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)
[...]
Freed by task 536:
kasan_save_stack (mm/kasan/common.c:57)
kasan_save_track (mm/kasan/common.c:78)
kasan_save_free_info (mm/kasan/generic.c:584)
__kasan_slab_free (mm/kasan/common.c:253 mm/kasan/common.c:285)
kfree (./include/linux/kasan.h:235 mm/slub.c:2677 mm/slub.c:6377 mm/slub.c:6692)
device_release (drivers/base/core.c:2636)
kobject_put (lib/kobject.c:689 lib/kobject.c:720 ./include/linux/kref.h:65 lib/kobject.c:737)
netdev_run_todo (net/core/dev.c:11756)
rtnl_dellink (net/core/rtnetlink.c:157 ./include/linux/rtnetlink.h:135 net/core/rtnetlink.c:3651)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)
[...]
Fix this by restoring skb->dev to the master at the end of each slave's
iteration.
Fixes:
|
||
|
Jamal Hadi Salim
|
816e90057a |
net/sched: sfq: clamp quantum to avoid signed overflow soft lockup
sfq_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) (unsigned). A
device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU
2147483634) makes psched_mtu() return 0x80000000, so slot->allot = INT_MIN
and INT_MIN + INT_MIN toggles between INT_MIN and 0 forever, spinning
sfq_dequeue() under the qdisc lock.
Clamp the quantum to [256, 1 << 20] so the refill loop terminates. The
lower bound also covers q->quantum == 0 (psched_mtu() returning 0),
which spins sfq_dequeue() identically. sfq_change() already rejects a
negative quantum, so only the init path was exposed.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes:
|
||
|
Jamal Hadi Salim
|
2164b512b9 |
net/sched: hhf: clamp quantum before hhf_change() to avoid overflow
hhf_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) with no overflow
check. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting
MTU 2147483634) makes weight * quantum overflow the signed deficit in
hhf_dequeue(), spinning forever.
Clamp q->quantum before hhf_change() so both the opt and !opt paths see
a sane quantum. Without this, bare "tc qdisc add ... hhf" succeeds with
a clamped quantum but "tc qdisc add ... hhf limit 1000" (any option
present) fails with -EINVAL because hhf_change() re-validates the
unclamped default (sch_hhf.c:559). 256 matches fq_codel's floor and is
a sane minimum for a DRR quantum.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes:
|
||
|
Jamal Hadi Salim
|
c86cd7ed0b |
net/sched: fq_pie: clamp default quantum to avoid signed overflow
fq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without
clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0
accepting MTU 2147483634) makes psched_mtu() return 0x80000000, which
overflows the signed flow->deficit to INT_MIN in fq_pie_qdisc_dequeue(),
causing an infinite loop and soft lockup. Emulate fq_pie_policy which
is already bounded to [1, 1 << 20]; clamp the default to [256, 1 << 20].
256 matches fq_codel's floor and is a sane minimum for a DRR quantum.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes:
|