CVE-2026-98372In the Linux kernel, the following vulnerability has been resolved:
xfrm: iptfs: fix stack OOB read in iptfs_skb_reset_frag_walk()
iptfs_skb_reset_frag_walk() advances to the fragment containing @offset
with an unbounded loop:
while (offset >= walk->past + walk->frags[walk->fragi].len)
walk->past += walk->frags[walk->fragi++].len;
walk->fragi is advanced and walk->frags[walk->fragi] is dereferenced
without ever checking fragi against walk->nr_frags. When the requested
offset is at or beyond the total length spanned by the walk's fragments,
fragi runs past nr_frags and off the end of the fixed-size on-stack
frags[MAX_SKB_FRAGS + 1] array, reading out-of-bounds stack memory.
The two callers behave differently: iptfs_skb_add_frags() already guards
against this with
if (!walk->nr_frags ||
offset >= walk->total + walk->initial_offset)
return len;
but iptfs_skb_can_add_frags() has no such guard and calls
iptfs_skb_reset_frag_walk() unconditionally, so it performs the
out-of-range walk. Its own "fragi < walk->nr_frags" bound check runs only
afterwards, too late to prevent the read.
This is reachable from the receive path: a crafted IP-TFS (AGGFRAG)
payload delivered to an IPTFS SA drives iptfs_reassem_cont() ->
iptfs_skb_can_add_frags() with an offset past the fragment total, e.g.:
BUG: KASAN: stack-out-of-bounds in iptfs_skb_reset_frag_walk+0x235/0x250
Read of size 4 at addr ffff888008ad7210 by task repro/345
iptfs_skb_reset_frag_walk+0x235/0x250 net/xfrm/xfrm_iptfs.c:392
iptfs_skb_can_add_frags+0x155/0x310 net/xfrm/xfrm_iptfs.c:420
iptfs_reassem_cont+0xcf8/0x1140 net/xfrm/xfrm_iptfs.c:902
iptfs_input_ordered+0x552/0x670 net/xfrm/xfrm_iptfs.c:1280
iptfs_input+0x3d6/0xde0 net/xfrm/xfrm_iptfs.c:1741
xfrm_input+0x282f/0x6140 net/xfrm/xfrm_input.c:700
xfrm4_esp_rcv+0x93/0x120 net/ipv4/xfrm4_protocol.c:104
ip_rcv+0x278/0x2d0 net/ipv4/ip_input.c:612
Give iptfs_skb_can_add_frags() the same up-front guard that
iptfs_skb_add_frags() already has, so the walk is never entered with an
out-of-range offset. When it triggers, the caller falls back to the
existing linearize-and-copy path, which is safe.
2026-10-06 · score —
CVE-2026-98371In the Linux kernel, the following vulnerability has been resolved:
xfrm: iptfs: fix runt reassembly panic from short inner tot_len
When the start of an inner packet is split across two outer packets
such that fewer than 4 bytes land at the end of the first one,
__input_process_payload() saves those bytes as a runt and skips the
iplen/iphlen validation performed for in-place packets. When the
continuation packet arrives, iptfs_reassem_cont() only requires the
declared inner length to be >= sizeof(ra_runt) (6) before allocating
the reassembly skb with that attacker-controlled length.
However, __iptfs_iphlen() always returns the fixed minimum IP header
size (20 for IPv4, 40 for IPv6), so for an inner IPv4 tot_len in
[6, 19] the header-completion copy writes past the declared packet
length, and the subsequent "ipremain -= copylen" underflows to ~4GB,
leaving the payload copy length bounded only by blkoff (up to 64KB).
At runtime the skb_put() tailroom check turns this into
skb_over_panic(), i.e. an unprivileged kernel panic (DoS), reachable
locally via userns+netns IPTFS SAs and remotely against IPTFS VPN
gateways when the decrypted outer skb is linear (e.g. AF_PACKET taps,
tun/tap delivery).
Align the runt path with the normal path by requiring the declared
inner length to cover at least the IP header size. This also subsumes
the previous >= sizeof(ra_runt) check, since the minimum IP header
is always larger than the runt buffer.
This issue was found by the autokbug dynamic kernel fuzzer at
Tencent Yunding Lab.
2026-10-06 · score —
CVE-2026-98370In the Linux kernel, the following vulnerability has been resolved:
xfrm: fix compat ALLOCSPI request use-after-free
xfrm_state_netlink() builds the ALLOCSPI response with
dump_one_state(), which already calls alloc_compat() with the response
skb and header.
xfrm_alloc_userspi() then calls alloc_compat() again, but passes the
original request skb and its header. For a compat request, the
translator therefore interprets the 228-byte compat xfrm_userspi_info
as the 232-byte native layout and reads four bytes past the declared
payload. It also publishes the translated child through the request's
frag_list.
A multicast clone of the request shares skb_shared_info and can observe
that child. xfrm_user_rcv_msg() frees it after the request handler
returns, racing a compat receiver which may still be copying from it and
resulting in a use-after-free.
Remove the redundant conversion. The response keeps its correct compat
translation from dump_one_state(), and no child is attached to the
inbound request.
2026-10-06 · score —
CVE-2026-98368In the Linux kernel, the following vulnerability has been resolved:
esp: downgrade zerocopy managed frags before mutating skb frags
On the out-of-place output path (esp->inplace == false) ESP rewrites the
skb frag array: esp_output_head() appends a trailer frag and
esp_output_tail() replaces the frags with a destination page, both
referenced with get_page().
When the skb carries zerocopy managed frags (SKBFL_MANAGED_FRAG_REFS) the
payload frags are owned by the ubuf and must not be referenced or
unreferenced individually, but ESP mutates the frag array without ever
downgrading the skb. This breaks the managed-frag invariant two ways:
- esp_ssg_unref() walks the source scatterlist and drops a page
reference for every frag, including the ubuf-owned payload frags,
pushing their refcount below the GUP pin bias while the pages are
still pinned, i.e. a use-after-free of the zerocopy pages;
- esp_output_tail() installs its destination page as frag 0 with
get_page() but leaves SKBFL_MANAGED_FRAG_REFS set, so
skb_release_data() takes the skip_unref branch and never drops that
reference, leaking the x->xfrag page at packet rate.
Fix this the way every other frag-mutating site does (__ip_append_data(),
__ip6_append_data(), tcp_sendmsg_locked()) and call
skb_zcopy_downgrade_managed() before ESP touches the frag array: it takes
a real reference on each existing frag and clears SKBFL_MANAGED_FRAG_REFS,
so the per-frag unref in esp_ssg_unref() and the frag release in
skb_release_data() are both balanced and no mixed-ownership frag array is
left behind.
2026-10-06 · score —
CVE-2026-98367In the Linux kernel, the following vulnerability has been resolved:
RDMA/siw: Clear association under lock if siw_qp_modify fails in siw_accept
We need to clear cep before release state_lock as siw_qp_llp_close and
siw_qp_modify->siw_qp_llp_close did.
Otherwise if siw_qp_modify() fails in siw_accept(), the QP's state_lock
is released before the error path cleanup. A concurrent ibv_modify_qp()
transitioning the QP to ERROR can race in this window:
siw_accept() ibv_modify_qp(ERROR)
---------------------- ----------------------
siw_qp_modify() fails
up_write(&qp->state_lock)
down_write(&qp->state_lock)
nextstate_from_idle():
if (qp->cep)
siw_cep_put(qp->cep) <- frees cep
qp->cep = NULL
goto error
cep->qp = NULL <- UAF
Clear qp->cep and drop the association reference taken by siw_cep_get(),
all under the write lock held from the initial down_write(&qp->state_lock).
Thread B therefore sees qp->cep == NULL, skips its own put, and cannot free
the cep before siw_accept() is done with it.
2026-10-06 · score —