Security Vulnerabilities
- CVEs Published In March 2024
In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Do not attempt to read past "commit"
When iterating over the ring buffer while the ring buffer is active, the
writer can corrupt the reader. There's barriers to help detect this and
handle it, but that code missed the case where the last event was at the
very end of the page and has only 4 bytes left.
The checks to detect the corruption by the writer to reads needs to see the
length of the event. If the length in the first 4 bytes is zero then the
length is stored in the second 4 bytes. But if the writer is in the process
of updating that code, there's a small window where the length in the first
4 bytes could be zero even though the length is only 4 bytes. That will
cause rb_event_length() to read the next 4 bytes which could happen to be off the
allocated page.
To protect against this, fail immediately if the next event pointer is
less than 8 bytes from the end of the commit (last byte of data), as all
events must be a minimum of 8 bytes anyway.
In the Linux kernel, the following vulnerability has been resolved:
net: nfc: fix races in nfc_llcp_sock_get() and nfc_llcp_sock_get_sn()
Sili Luo reported a race in nfc_llcp_sock_get(), leading to UAF.
Getting a reference on the socket found in a lookup while
holding a lock should happen before releasing the lock.
nfc_llcp_sock_get_sn() has a similar problem.
Finally nfc_llcp_recv_snl() needs to make sure the socket
found by nfc_llcp_sock_from_sn() does not disappear.
In the Linux kernel, the following vulnerability has been resolved:
tee: amdtee: fix use-after-free vulnerability in amdtee_close_session
There is a potential race condition in amdtee_close_session that may
cause use-after-free in amdtee_open_session. For instance, if a session
has refcount == 1, and one thread tries to free this session via:
kref_put(&sess->refcount, destroy_session);
the reference count will get decremented, and the next step would be to
call destroy_session(). However, if in another thread,
amdtee_open_session() is called before destroy_session() has completed
execution, alloc_session() may return 'sess' that will be freed up
later in destroy_session() leading to use-after-free in
amdtee_open_session.
To fix this issue, treat decrement of sess->refcount and removal of
'sess' from session list in destroy_session() as a critical section, so
that it is executed atomically.
In the Linux kernel, the following vulnerability has been resolved:
x86/alternatives: Disable KASAN in apply_alternatives()
Fei has reported that KASAN triggers during apply_alternatives() on
a 5-level paging machine:
BUG: KASAN: out-of-bounds in rcu_is_watching()
Read of size 4 at addr ff110003ee6419a0 by task swapper/0/0
...
__asan_load4()
rcu_is_watching()
trace_hardirqs_on()
text_poke_early()
apply_alternatives()
...
On machines with 5-level paging, cpu_feature_enabled(X86_FEATURE_LA57)
gets patched. It includes KASAN code, where KASAN_SHADOW_START depends on
__VIRTUAL_MASK_SHIFT, which is defined with cpu_feature_enabled().
KASAN gets confused when apply_alternatives() patches the
KASAN_SHADOW_START users. A test patch that makes KASAN_SHADOW_START
static, by replacing __VIRTUAL_MASK_SHIFT with 56, works around the issue.
Fix it for real by disabling KASAN while the kernel is patching alternatives.
[ mingo: updated the changelog ]
In the Linux kernel, the following vulnerability has been resolved:
phy: lynx-28g: serialize concurrent phy_set_mode_ext() calls to shared registers
The protocol converter configuration registers PCC8, PCCC, PCCD
(implemented by the driver), as well as others, control protocol
converters from multiple lanes (each represented as a different
struct phy). So, if there are simultaneous calls to phy_set_mode_ext()
to lanes sharing the same PCC register (either for the "old" or for the
"new" protocol), corruption of the values programmed to hardware is
possible, because lynx_28g_rmw() has no locking.
Add a spinlock in the struct lynx_28g_priv shared by all lanes, and take
the global spinlock from the phy_ops :: set_mode() implementation. There
are no other callers which modify PCC registers.
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Set all reserved memblocks on Node#0 at initialization
After commit 61167ad5fecdea ("mm: pass nid to reserve_bootmem_region()")
we get a panic if DEFERRED_STRUCT_PAGE_INIT is enabled:
[ 0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000000000002b82, era == 90000000040e3f28, ra == 90000000040e3f18
[ 0.000000] Oops[#1]:
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.5.0+ #733
[ 0.000000] pc 90000000040e3f28 ra 90000000040e3f18 tp 90000000046f4000 sp 90000000046f7c90
[ 0.000000] a0 0000000000000001 a1 0000000000200000 a2 0000000000000040 a3 90000000046f7ca0
[ 0.000000] a4 90000000046f7ca4 a5 0000000000000000 a6 90000000046f7c38 a7 0000000000000000
[ 0.000000] t0 0000000000000002 t1 9000000004b00ac8 t2 90000000040e3f18 t3 90000000040f0800
[ 0.000000] t4 00000000000f0000 t5 80000000ffffe07e t6 0000000000000003 t7 900000047fff5e20
[ 0.000000] t8 aaaaaaaaaaaaaaab u0 0000000000000018 s9 0000000000000000 s0 fffffefffe000000
[ 0.000000] s1 0000000000000000 s2 0000000000000080 s3 0000000000000040 s4 0000000000000000
[ 0.000000] s5 0000000000000000 s6 fffffefffe000000 s7 900000000470b740 s8 9000000004ad4000
[ 0.000000] ra: 90000000040e3f18 reserve_bootmem_region+0xec/0x21c
[ 0.000000] ERA: 90000000040e3f28 reserve_bootmem_region+0xfc/0x21c
[ 0.000000] CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
[ 0.000000] PRMD: 00000000 (PPLV0 -PIE -PWE)
[ 0.000000] EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
[ 0.000000] ECFG: 00070800 (LIE=11 VS=7)
[ 0.000000] ESTAT: 00010800 [PIL] (IS=11 ECode=1 EsubCode=0)
[ 0.000000] BADV: 0000000000002b82
[ 0.000000] PRID: 0014d000 (Loongson-64bit, Loongson-3A6000)
[ 0.000000] Modules linked in:
[ 0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____))
[ 0.000000] Stack : 0000000000000000 9000000002eb5430 0000003a00000020 90000000045ccd00
[ 0.000000] 900000000470e000 90000000002c1918 0000000000000000 9000000004110780
[ 0.000000] 00000000fe6c0000 0000000480000000 9000000004b4e368 9000000004110748
[ 0.000000] 0000000000000000 900000000421ca84 9000000004620000 9000000004564970
[ 0.000000] 90000000046f7d78 9000000002cc9f70 90000000002c1918 900000000470e000
[ 0.000000] 9000000004564970 90000000040bc0e0 90000000046f7d78 0000000000000000
[ 0.000000] 0000000000004000 90000000045ccd00 0000000000000000 90000000002c1918
[ 0.000000] 90000000002c1900 900000000470b700 9000000004b4df78 9000000004620000
[ 0.000000] 90000000046200a8 90000000046200a8 0000000000000000 9000000004218b2c
[ 0.000000] 9000000004270008 0000000000000001 0000000000000000 90000000045ccd00
[ 0.000000] ...
[ 0.000000] Call Trace:
[ 0.000000] [<90000000040e3f28>] reserve_bootmem_region+0xfc/0x21c
[ 0.000000] [<900000000421ca84>] memblock_free_all+0x114/0x350
[ 0.000000] [<9000000004218b2c>] mm_core_init+0x138/0x3cc
[ 0.000000] [<9000000004200e38>] start_kernel+0x488/0x7a4
[ 0.000000] [<90000000040df0d8>] kernel_entry+0xd8/0xdc
[ 0.000000]
[ 0.000000] Code: 02eb21ad 00410f4c 380c31ac <262b818d> 6800b70d 02c1c196 0015001c 57fe4bb1 260002cd
The reason is early memblock_reserve() in memblock_init() set node id to
MAX_NUMNODES, making NODE_DATA(nid) a NULL dereference in the call chain
reserve_bootmem_region() -> init_reserved_page(). After memblock_init(),
those late calls of memblock_reserve() operate on subregions of memblock
.memory regions. As a result, these reserved regions will be set to the
correct node at the first iteration of memmap_init_reserved_pages().
So set all reserved memblocks on Node#0 at initialization can avoid this
panic.
In the Linux kernel, the following vulnerability has been resolved:
nfc: nci: assert requested protocol is valid
The protocol is used in a bit mask to determine if the protocol is
supported. Assert the provided protocol is less than the maximum
defined so it doesn't potentially perform a shift-out-of-bounds and
provide a clearer error for undefined protocols vs unsupported ones.
In the Linux kernel, the following vulnerability has been resolved:
nvme-fc: Prevent null pointer dereference in nvme_fc_io_getuuid()
The nvme_fc_fcp_op structure describing an AEN operation is initialized with a
null request structure pointer. An FC LLDD may make a call to
nvme_fc_io_getuuid passing a pointer to an nvmefc_fcp_req for an AEN operation.
Add validation of the request structure pointer before dereference.
In the Linux kernel, the following vulnerability has been resolved:
ravb: Fix use-after-free issue in ravb_tx_timeout_work()
The ravb_stop() should call cancel_work_sync(). Otherwise,
ravb_tx_timeout_work() is possible to use the freed priv after
ravb_remove() was called like below:
CPU0 CPU1
ravb_tx_timeout()
ravb_remove()
unregister_netdev()
free_netdev(ndev)
// free priv
ravb_tx_timeout_work()
// use priv
unregister_netdev() will call .ndo_stop() so that ravb_stop() is
called. And, after phy_stop() is called, netif_carrier_off()
is also called. So that .ndo_tx_timeout() will not be called
after phy_stop().
In the Linux kernel, the following vulnerability has been resolved:
ieee802154: ca8210: Fix a potential UAF in ca8210_probe
If of_clk_add_provider() fails in ca8210_register_ext_clock(),
it calls clk_unregister() to release priv->clk and returns an
error. However, the caller ca8210_probe() then calls ca8210_remove(),
where priv->clk is freed again in ca8210_unregister_ext_clock(). In
this case, a use-after-free may happen in the second time we call
clk_unregister().
Fix this by removing the first clk_unregister(). Also, priv->clk could
be an error code on failure of clk_register_fixed_rate(). Use
IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().