| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Do not show buffer_meta for CPUs without a buffer
The per_cpu/cpuN/buffer_meta files are created for every possible CPU,
but buffer->buffers[cpu] is only allocated once that CPU comes online.
Reading the file of a CPU that never came online dereferences a NULL
cpu_buffer in rbm_start().
Fail the open with -ENODEV when the CPU has no buffer, as the other
per CPU ring buffer interfaces do. |
| In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx()
On a persistent ring buffer, rb_meta_subbuf_idx() can return an index one
sub-buffer too high. rb_setup_ids_meta_page() then fills subbuf_ids[]
shifted by one and leaves subbuf_ids[0] NULL, which __rb_map_vma()
dereferences when userspace maps trace_pipe_raw. rb_update_meta_reader()
writes two such indices into meta->buffers[], which rb_cpu_meta_valid()
would reject on the next boot, discarding the previous boot's trace.
A CPU's sub-buffer array starts after its meta header and the nr_subbufs
integers that follow, aligned up to a sub-buffer. rb_meta_subbuf_idx()
inverts that calculation but skips only the integers, not the header, so
its base is one sub-buffer low whenever the omitted header size crosses
the alignment boundary.
Invert the calculation with rb_subbufs_from_meta() rather than repeating
it. rb_range_buffer() maps an index back to an address through the same
helper, so the two directions can no longer disagree. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: bsg: Pass reply_len to bsg_setup_queue() to fit UFS ARPMB replies
bsg-lib allocates a 96-byte (SCSI_SENSE_BUFFERSIZE) reply buffer per
job, but struct ufs_rpmb_reply is 104 bytes: a 40-byte struct
ufs_bsg_reply followed by a 64-byte EHS. When an Advanced RPMB command
returns an EHS, ufshcd_advanced_rpmb_req_handler() copies it right after
the 40-byte header and writes 8 bytes past the end of the buffer.
Let each BSG transport pass its reply buffer size to bsg_setup_queue()
and have ufs_bsg request sizeof(struct ufs_rpmb_reply), so the full
reply reaches user space. Other transports keep SCSI_SENSE_BUFFERSIZE. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: st: Fix use-after-free race between st_remove() and st_open()
st_remove() drops the probe reference on the scsi_tape with kref_put()
and only afterwards removes its index from st_index_idr. If that was the
last reference, scsi_tape_release() frees the structure while it is
still published in the idr.
scsi_tape_get(), called from st_open(), looks up the tape in
st_index_idr and takes a reference under st_ref_mutex and
st_index_lock. remove_cdevs() does not wait for opens that are already
past chrdev_open(), so an open that is blocked on st_ref_mutex while
st_remove() holds it can take the mutex as soon as st_remove() drops it,
find the freed tpnt in the idr and call kref_get() on it:
BUG: KASAN: slab-use-after-free in st_open
Write of size 4 ...
st_open (drivers/scsi/st.c:254 drivers/scsi/st.c:1291)
chrdev_open
...
Freed by task ...:
kfree
st_remove (drivers/scsi/st.c:4512)
Remove the index from the idr before dropping the reference, all under
st_ref_mutex. A concurrent scsi_tape_get() now either runs first and
holds a valid reference that keeps the tape alive, or runs afterwards
and finds nothing, so st_open() fails with -ENXIO.
This restores the ordering st_remove() had before the conversion to
st_index_idr, where the tape was unpublished from scsi_tapes[] before
the final kref_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: libiscsi: Validate the ITT reflected in a Reject PDU
A Reject PDU carries a copy of the header it rejects, and
iscsi_handle_reject() takes the ITT out of that copy to find the task to
clean up:
memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
...
task = iscsi_itt_to_task(conn, rejected_pdu.itt);
That value is whatever the target put there. iscsi_itt_to_task() bounds
the index against cmds_max and checks nothing else, so any task in the
pool can be named, and iscsi_nop_out_rsp() then completes it.
An index that has never been used gives a NULL task->conn: the pool is
zeroed at session setup and conn is assigned only when a task is
allocated. If the task was used and returned, iscsi_complete_task() hits
its WARN_ON_ONCE(task->state == ISCSI_TASK_FREE) and the refcount
underflows. An in-flight SCSI command is completed as successful - a 1
MiB read returned 1048576 with none of its buffer written and no
warning.
Validate the reflected ITT the way iscsi_itt_to_ctask() validates a
command ITT, and require the task to be in flight and not a SCSI
command.
[ 6.248477] Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI
[ 6.249357] KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
[ 6.249951] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 7.2.0-rc5-ISCSI1-gf5098b6bae76 #1 PREEMPT(lazy)
[ 6.250718] 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
[ 6.251616] RIP: 0010:iscsi_nop_out_rsp.constprop.0+0x46/0x160
[ 6.252043] Code: c1 ea 03 48 83 ec 08 80 3c 02 00 0f 85 f5 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 58 48 8d 7d 60 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 c0 00 00 00 48 8b 45 60 48 39 c3 74 50 48 b8 00
[ 6.252813] RSP: 0018:ffff88806c907b80 EFLAGS: 00010206
[ 6.253042] RAX: dffffc0000000000 RBX: ffff88800607e000 RCX: ffffffff8d571a25
[ 6.253345] RDX: 000000000000000c RSI: ffff88806c907c38 RDI: 0000000000000060
[ 6.253642] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff235a504
[ 6.253947] R10: 0000000000000003 R11: 7463656e6e6f6320 R12: 0000000000000000
[ 6.254251] R13: 0000000000000000 R14: ffff88806c907c38 R15: 0000000000000000
[ 6.254549] FS: 0000000000000000(0000) GS:ffff8880d95bc000(0000) knlGS:0000000000000000
[ 6.254887] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6.255140] CR2: 00007fc393e8ffc0 CR3: 0000000005252006 CR4: 0000000000770ef0
[ 6.255439] PKRU: 55555554
[ 6.255564] Call Trace:
[ 6.255674] <IRQ>
[ 6.255768] __iscsi_complete_pdu+0x18bf/0x22a0
[ 6.256733] iscsi_complete_pdu+0x54/0xa0
[ 6.256905] iscsi_tcp_data_recv_done+0xf4/0x250
[ 6.257103] iscsi_tcp_recv_skb+0x31e/0xec0
[ 6.257680] iscsi_sw_tcp_recv+0x12f/0x390
[ 6.258061] __tcp_read_sock+0x1ab/0x810
[ 6.258853] iscsi_sw_tcp_data_ready+0x18b/0x510
[ 6.259808] tcp_data_queue+0x1f13/0x4cd0
[ 6.260567] tcp_rcv_established+0x8a5/0x3a00
[ 6.261931] tcp_v4_do_rcv+0x449/0x960
[ 6.262269] tcp_v4_rcv+0x2245/0x3bc0 |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: libiscsi: Validate the task named by a management response
__iscsi_complete_pdu() fetches the task for five response types from one
place and checks only that the index resolved:
case ISCSI_OP_LOGOUT_RSP:
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_SCSI_TMFUNC_RSP:
case ISCSI_OP_NOOP_IN:
task = iscsi_itt_to_task(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
iscsi_itt_to_task() bounds the index against cmds_max and looks at
nothing else, so a target can name any slot in the pool, including one
that has never been used. task->conn is then NULL, and both
iscsi_nop_out_rsp() and iscsi_complete_task() dereference it. One
unsolicited NOP-In is enough; a Text Response carrying the same ITT
crashes in iscsi_complete_task() instead.
Require the task to be in flight and not a SCSI command, the way
iscsi_itt_to_ctask() does for the command opcodes.
[ 6.298634] Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI
[ 6.298642] KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
[ 6.298652] CPU: 1 UID: 0 PID: 111 Comm: iscsistart Not tainted 7.2.0-rc5-ISCSI1-gf5098b6bae76 #1 PREEMPT(lazy)
[ 6.298654] 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
[ 6.298656] RIP: 0010:iscsi_nop_out_rsp.constprop.0+0x46/0x160
[ 6.298691] Code: c1 ea 03 48 83 ec 08 80 3c 02 00 0f 85 f5 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 58 48 8d 7d 60 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 c0 00 00 00 48 8b 45 60 48 39 c3 74 50 48 b8 00
[ 6.298698] RSP: 0018:ffff88806c907be8 EFLAGS: 00010206
[ 6.298701] RAX: dffffc0000000000 RBX: ffff888006116800 RCX: 0000000000000020
[ 6.298702] RDX: 000000000000000c RSI: ffff88800525d578 RDI: 0000000000000060
[ 6.298703] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[ 6.298706] R10: 0000000000000020 R11: 0000000000000000 R12: 0000000000000000
[ 6.298706] R13: 000000000000002e R14: ffff8880056eb440 R15: ffff888006116800
[ 6.298707] FS: 00007fc02d1c2740(0000) GS:ffff8880b29bc000(0000) knlGS:0000000000000000
[ 6.298710] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6.298711] CR2: 000055fe3b56ddf8 CR3: 00000000053b9004 CR4: 0000000000770ef0
[ 6.298712] PKRU: 55555554
[ 6.298713] Call Trace:
[ 6.298714] <IRQ>
[ 6.298714] __iscsi_complete_pdu+0x13a8/0x22a0
[ 6.298758] iscsi_complete_pdu+0x54/0xa0
[ 6.298759] iscsi_tcp_hdr_recv_done+0x870/0x2c80
[ 6.298778] iscsi_tcp_recv_skb+0x31e/0xec0
[ 6.298800] iscsi_sw_tcp_recv+0x12f/0x390
[ 6.298804] __tcp_read_sock+0x1ab/0x810
[ 6.298812] iscsi_sw_tcp_data_ready+0x18b/0x510
[ 6.298814] tcp_rcv_established+0x1f56/0x3a00
[ 6.298842] tcp_v4_do_rcv+0x449/0x960
[ 6.298847] tcp_v4_rcv+0x2245/0x3bc0 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: keep the eviction fence until the last handle is closed
amdgpu_gem_object_close() detaches the user queue eviction fence from
the BO before it checks bo_va->ref_count, so closing any handle of a BO
removes the fence, even when the file still has another handle to the
BO and the bo_va with its GPU mappings stays. The BO can then be evicted
without suspending the user queues of the file, which keep accessing it
through mappings that are only marked for update.
Seen on navi31 with a SDMA user queue: a BO opened twice in the same
file (GEM_FLINK + GEM_OPEN) loses its eviction fence when the second
handle is closed (traced attach/detach of the fence):
attach bo=ffff8c78a6c84c00
GEM_CLOSE handle=7
detach bo=ffff8c78a6c84c00
while handle 6 and the mapping are still in use.
Only detach the fence when the last reference to the bo_va goes away,
matching amdgpu_gem_object_open(), which attaches it only when the
bo_va is created. With this the fence stays until the file is closed.
(cherry picked from commit 8387982f03d4026b7dc11b0b5e3118298eee4d6a) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/exec: don't immediately add prelocked obj to array of locked objs
When a contention is detected the drm_exec object grabs a reference to
the contended object, unlocks all other objects and pre-locks the
contended one before anything else.
The problem is that it is possible that this pre-locked object was about
to be destroyed and drm_exec is now holding the last reference to it.
So we never actually see this pre-locked object again to be explicitly
locked and so also never reserve a slot for a dma_fence object on it.
Should the driver now use drm_exec_for_each_locked_object() to add a new
fence to all locked objects we eventually see a warning or even a
BUG_ON() to prevent random memory corruption.
Fix this by keeping the prelocked object out of the array of locked objs
until it was explicitly mentioned by the driver again.
If the prelocked object is never mentioned again by the driver
just unlock and drop the reference at the end of the locking loop. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Don't transfer shrinker pages for pinned bos on purgeable state change
Pinned bos have their pages removed from the shrinker's shrinkable /
purgeable counts on pin, and added back on unpin according to the
bo's purgeable state at that time.
However, xe_bo_set_purgeable_shrinker() unconditionally transfers
pages between the shrinkable and purgeable counts. If the purgeable
state of a pinned bo changes, for example by userspace madvising
DONTNEED on a VMA of a bo that is also pinned as a scanout buffer,
this underflows one count and, after unpin, leaves the other one
permanently inflated.
Only update the purgeable flag for pinned bos, and leave the page
accounting to unpin.
(cherry picked from commit afe6bc012034123fd838328668e609bf57e46bd3) |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Fix use-after-free of a destroyed user DSQ by a deferred reenqueue
A deferred reenqueue can read a freed user DSQ. The request stays on its
CPU's deferred list until run_deferred() takes it, and the RCU callback that
frees the DSQ assumes that the grace period has flushed it, so exit_dsq()
checks the per-CPU node without the deferred list lock. A grace period waits
for readers in flight, not for a pending run_deferred(). A run_deferred()
which starts after the grace period began can detach the request right
before the callback looks and then read the freed DSQ's id.
Cancel the pending requests before the grace period instead. The irq work
that frees the DSQ unlinks every CPU's request under the per-CPU deferred
list lock, and schedule_dsq_reenq() ignores a new request under the same
lock once the id is invalid. Only a run_deferred() that started before the
grace period can hold a request, and it runs with IRQs disabled, so the
grace period waits for it and nothing touches the DSQ after the callback. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix crash in print_graph_function_event()
tracing_set_tracer() assigns the flags of the newly selected tracer
with:
tr->current_trace_flags = t->flags ? : t->tracer->flags;
If the new tracer defines neither static flags nor default flags, like
hwlat, irqsoff or wakeup, add_tracer() has no per instance flags copy
for it, and both operands are NULL, so tr->current_trace_flags ends up
being NULL as well.
The ring buffer is not cleared when switching tracers: it is reset
inside tracer_init(), after current_trace_flags was already assigned.
If the buffer still holds function_graph entries of the previous
tracer, printing one of them dereferences the NULL pointer. This was
hit by cat trace during an ftrace stress test:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
RIP: 0010:print_graph_function_event+0xe/0x20
Call Trace:
s_show+0x4d/0x110
seq_read_iter+0x2d4/0x490
seq_read+0x130/0x170
vfs_read+0xb5/0x370
ksys_read+0x6d/0xe0
do_syscall_64+0xbc/0x450
The snapshot buffer is not reset at all, so this can be reproduced
without a race:
echo function_graph > /sys/kernel/tracing/current_tracer
echo 1 > /sys/kernel/tracing/snapshot
echo hwlat > /sys/kernel/tracing/current_tracer
cat /sys/kernel/tracing/snapshot
Rather than teaching every user of tr->current_trace_flags about this
corner case, make sure it is never NULL: when the newly selected
tracer has no flags at all, tracing_set_tracer() falls back to a
static empty no_tracer_flags. run_tracer_selftest() can hit the same
case, so the same fallback is added there too. The existing users
already handle opts == NULL, so these tracers keep behaving as before. |
| In the Linux kernel, the following vulnerability has been resolved:
dm-integrity: fix infinite loop on discard with large tag size
When integrity_metadata handles a discard, it fills a buffer with
DISCARD_FILLER and writes it over the tags, max_blocks blocks at a
time. If the kmalloc fails, the buffer is the on-stack array
checksums_onstack and max_size is set to HASH_MAX_DIGESTSIZE. So if the
tag size is larger than HASH_MAX_DIGESTSIZE, max_blocks is zero, bi_size
is never decremented and the loop never terminates.
Fix this by using sizeof(checksums_onstack) as max_size. The array has
MAX_TAG_SIZE bytes since commit b93b6643e9b5 ("dm integrity: fix a
crash with unusually large tag size"), so max_blocks is at least 1. |
| In the Linux kernel, the following vulnerability has been resolved:
page_pool: keep frag_offset aligned for odd-sized requests
page_pool_alloc_frag_netmem() rounds the requested fragment size with
size = ALIGN(size, dma_get_cache_alignment());
dma_get_cache_alignment() returns 1 unless the architecture defines
ARCH_DMA_MINALIGN, which DMA-coherent architectures such as x86 do not.
There the ALIGN() is a no-op and pool->frag_offset advances by the raw,
unrounded size.
A single caller asking for an odd size then leaves frag_offset misaligned
for every fragment carved out of that page afterwards. The pool is shared,
so the damage is not confined to the caller that caused it.
The per-cpu system_page_pool used by generic XDP hits this.
skb_pp_cow_data() allocates its fragments with the raw packet length:
size = min_t(u32, len, PAGE_SIZE);
truesize = size;
page = page_pool_dev_alloc(pool, &page_off, &truesize);
leaving frag_offset odd for whatever is carved out of that page next. Its
own head allocation is already aligned -- SKB_HEAD_ALIGN(size) plus the
XDP_PACKET_HEADROOM its callers pass -- so it is a later user of the shared
pool that pays: page_pool_dev_alloc_va() returns a misaligned buffer,
napi_build_skb() installs it as skb->head, and skb_shinfo(skb) ==
skb->head + skb->end is misaligned with it.
skb_shinfo()->dataref is a 4-byte atomic_t at offset 0x20, so the
atomic_inc() in __skb_clone() straddles a cache line. On x86 with split
lock detection -- fatal for kernel split locks by default -- this panics
the machine:
Oops: Split lock detected
RIP: 0010:skb_clone+0x154/0x1e0
Call Trace:
<IRQ>
raw_local_deliver+0x1ed/0x2c0
ip_protocol_deliver_rcu+0x54/0x1c0
ip_local_deliver_finish+0x85/0x100
ip_local_deliver+0x67/0x100
__netif_receive_skb_one_core+0x85/0xa0
process_backlog+0x87/0x130
Reproduced by attaching any generic-mode XDP program to loopback and
opening a RAW IPPROTO_UDP socket, which makes raw_local_deliver() clone
every locally delivered UDP packet; ordinary DNS traffic then triggers it,
roughly once per 2500 clones. Observed on 6.12.101 and 7.1.8.
Tracing page_pool_alloc_frag_netmem() over one such run shows the
amplification -- two odd-sized requests, nine misaligned offsets:
requested size & 7: 0: 17035 5: 1 7: 1
frag_offset & 7: 0: 17028 3: 1 4: 1 5: 1 6: 1 7: 5
and skb_pp_cow_data() returning heads that were aligned on entry:
head 0xffff8f4c86aeac00 -> 0xffff8f4c53a9a9c4 (&7=4)
head 0xffff8f4d6a8a42c0 -> 0xffff8f4c4f7b7a45 (&7=5)
Round the fragment size up to at least the alignment struct skb_shared_info
requires, so fragments are always suitably aligned for the objects callers
build on them. Architectures needing a larger DMA alignment keep it.
This also makes the remainder computed in page_pool_alloc_netmem(),
*size = max_size - *offset;
aligned, since max_size is a power of two -- which fixes the matching
misalignment of skb->end.
Verified with a controlled A/B under QEMU/KVM: same tree, same config,
same compiler, same rootfs and identical traffic, differing only by this
patch. A SEC("xdp.frags") XDP_PASS program on lo plus UDP datagrams
larger than max_head_size drives skb_pp_cow_data()'s fragment loop, which
passes raw packet lengths to the pool. Measured at the return of
skb_pp_cow_data():
unpatched patched
skb_pp_cow_data calls 40800 40800
misaligned skb->head 1120 0
dataref at line offset >60 80 0
The last row counts the accesses that actually fault:
skb_shinfo()->dataref sits at head+end+0x20 and is a 4-byte atomic, so
`lock incl` splits a 64-byte cache line only when that address lands at
offset 61..63. All 80 occurrences were at offset 61; the panic reported
above was at offset 62. Eliminating the misalignment removes every one
of them.
Same class of bug as commit 3bed3cc4156e ("net: Do not allocate page
fragments t
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
s390/ctcm: Prevent XID null dereference
The mpc_validate_xid() function sets grp->saved_xid2->xid2_flag2 to 0x40
to signal XID validation error. If peer XID is NULL or r/w channel
pairing mismatch happens, grp->saved_xid2 is never initialized. An
attempt to set the flag in such case leads to NULL dereference.
Fix this by using the always available priv->xid->xid2_flag2 instead of
grp->saved_xid2->xid2_flag2 for validation errors. |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: validate packet source for connected sockets
virtio_transport_recv_pkt() looks up sockets first by the full source and
destination tuple, then by destination only in the bound table. The
fallback is needed for listening and connecting sockets, but sockets remain
in the bound table after connect(), so it can also return a non-listening
socket.
The fallback does not validate the source address. In TCP_SYN_SENT, a
RESPONSE from an unrelated source can transition the victim socket to
TCP_ESTABLISHED while its stored remote address remains unchanged.
Subsequent RW packets from that source are delivered through the same
destination-only fallback.
This was reproduced with capability-empty processes under different UIDs.
The attacker discovered the target tuple through unprivileged AF_VSOCK
sock_diag and caused the victim socket to read 16 attacker-chosen bytes;
the intended peer-side socket read 0 of those 16 bytes.
Add vsock_check_source() to validate the transport, source port and source
CID against the peer stored in a non-listening socket. The local transport
is the CID exception because its packets are generated internally with
VMADDR_CID_LOCAL as their source, including connections using CID aliases.
Use the helper after lock_sock() in the virtio receive path. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/userq: actually validate userq BOs
This was supposed to loop over the individual evicted list, as the
kernel and always_valid evicted lists were already handled in
amdgpu_vm_validate.
Without this, BOs that were created and evicted before a userq was made
would never end up in an eviction fence rearm.
Also add the missing ref to the BO before drm_exec locks and refs it.
(cherry picked from commit 18decfc9e8cc0fa70b6de9944cc27a37729edfbd) |
| In the Linux kernel, the following vulnerability has been resolved:
net: bridge: mcast: don't truncate the port group walk on teardown
__br_multicast_disable_port_ctx() and br_multicast_del_port() walk
port->mglist with hlist_for_each_entry_safe(). However,
br_multicast_find_del_pg() can also delete other entries from the same
list through br_multicast_fwd_src_remove() or __fwd_del_star_excl().
If such an entry is the iterator's saved next node, hlist_del_init()
clears its ->next and terminates the walk early. The reproducer triggers
this in both teardown walks, leaving port groups in the bridge mdb with
a dangling ->key.port after del_nbp() frees the port:
BUG: KASAN: slab-use-after-free in __mdb_fill_info+0x1191/0x1320
__mdb_fill_info+0x1191/0x1320
br_mdb_dump+0x594/0xe40
rtnl_mdb_dump+0x1cf/0x5d0
Use hlist_del_init_rcu() to unlink the group while preserving ->next.
br_multicast_del_pg() and the teardown walks run under
br->multicast_lock. The GC worker must acquire the same lock before
detaching the group for destruction, so the node remains alive while
the walk uses the preserved pointer.
Preserving ->next means a walk can now reach a group that an earlier
iteration already deleted as a side effect. That group is off mp->ports,
so br_multicast_find_del_pg() would fall through its port scan and hit
the trailing WARN_ON(1). Skip such groups at the top of that helper: a
port group is put on port->mglist when it is created and only unlinked
when it is deleted, so hlist_unhashed() identifies exactly this case. |
| In the Linux kernel, the following vulnerability has been resolved:
net: psp: do not inherit the Rx association on clone
sk->psp_assoc sits past sk_dontcopy_end, so sock_copy() copies it into
every socket accepted from a listener without taking a reference, while
inet_sock_destruct() puts for every inet socket. psp_twsk_init() does
refcount_inc() for the timewait socket, so a child closing through
TIME_WAIT cancels its own put and leaves the association with one
reference and N timewait sockets holding the same pointer. Closing the
listener frees it, and the timewait timers then put freed memory.
Rejecting the association on a listening socket is not sufficient: a socket
can acquire one while established and then be turned back into a listener,
because tcp_disconnect() leaves sk->psp_assoc in place.
BUG: KASAN: slab-use-after-free in psp_twsk_assoc_free+0x6f/0xf0
Write of size 4 at addr ffff888110f9255c by task swapper/7/0
psp_twsk_assoc_free+0x6f/0xf0
inet_twsk_put+0xda/0x1b0
call_timer_fn+0x53/0x2e0
__run_timers+0x764/0xa80
Freed by task 99:
kfree+0x1a7/0x500
process_one_work+0x7ec/0x1100
An association carries a per-connection SPI and key, so a child must not
inherit the parent's. Clear it on clone. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fill in FileSysIdentifier in FS_POSIX_INFORMATION
smb2_get_info_filesystem() reports 56 bytes for FS_POSIX_INFORMATION,
that is the whole of FILE_SYSTEM_POSIX_INFO, but never assigns
FileSysIdentifier. Those eight bytes go to the client as they are found
in the response buffer.
The buffer is zeroed on allocation, so a standalone request leaks
nothing. A compound request can leak: the offset of the next response
is advanced by the length pinned for the previous one, so a reply that
was written into the buffer and then dropped in favour of the short
error response of smb2_set_err_rsp() stays there, and the next reply is
laid over it with only the header cleared.
Report the file system id statfs() returned, which is what the field is
for. FileSysIdentifier is __le64 and f_fsid is a pair of ints, so
assemble the value first, val[0] as the low half, and convert it on the
way out. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix data corruption with concurrent writes and O_TRUNC
cifs_do_truncate() flushes dirty pages with filemap_write_and_wait()
and truncates the file on the server, but in the old code both
operations ran without holding i_rwsem or invalidate_lock. A
concurrent buffered write via netfs_perform_write() -- which only
needs i_rwsem shared -- could dirty new pages after the flush but
before the local truncation, and those pages would be silently
discarded by cifs_setsize() -> truncate_pagecache().
Fix by acquiring inode_lock (exclusive i_rwsem) and
filemap_invalidate_lock at the top of cifs_do_truncate(), so the
entire flush-truncate-resize sequence is atomic with respect to:
- buffered writes (blocked by exclusive i_rwsem, since
netfs_start_io_write takes i_rwsem shared),
- read page faults (blocked by exclusive invalidate_lock, since
filemap_fault takes it shared),
- writeback collection (blocked by netfs_wb_begin/netfs_wb_end
around the server truncate and local resize, since
netfs_writepages also acquires the wb lock). |
