| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
openvswitch: Fix unsafe attribute parsing in output_userspace()
This patch replaces the manual Netlink attribute iteration in
output_userspace() with nla_for_each_nested(), which ensures that only
well-formed attributes are processed. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: fix region locking in hash types
Region locking introduced in v5.6-rc4 contained three macros to handle
the region locks: ahash_bucket_start(), ahash_bucket_end() which gave
back the start and end hash bucket values belonging to a given region
lock and ahash_region() which should give back the region lock belonging
to a given hash bucket. The latter was incorrect which can lead to a
race condition between the garbage collector and adding new elements
when a hash type of set is defined with timeouts. |
| In the Linux kernel, the following vulnerability has been resolved:
module: ensure that kobject_put() is safe for module type kobjects
In 'lookup_or_create_module_kobject()', an internal kobject is created
using 'module_ktype'. So call to 'kobject_put()' on error handling
path causes an attempt to use an uninitialized completion pointer in
'module_kobject_release()'. In this scenario, we just want to release
kobject without an extra synchronization required for a regular module
unloading process, so adding an extra check whether 'complete()' is
actually required makes 'kobject_put()' safe. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: typec: ucsi: displayport: Fix NULL pointer access
This patch ensures that the UCSI driver waits for all pending tasks in the
ucsi_displayport_work workqueue to finish executing before proceeding with
the partner removal. |
| In the Linux kernel, the following vulnerability has been resolved:
net_sched: Flush gso_skb list too during ->change()
Previously, when reducing a qdisc's limit via the ->change() operation, only
the main skb queue was trimmed, potentially leaving packets in the gso_skb
list. This could result in NULL pointer dereference when we only check
sch->limit against sch->q.qlen.
This patch introduces a new helper, qdisc_dequeue_internal(), which ensures
both the gso_skb list and the main queue are properly flushed when trimming
excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie)
are updated to use this helper in their ->change() routines. |
| In the Linux kernel, the following vulnerability has been resolved:
parisc: Fix double SIGFPE crash
Camm noticed that on parisc a SIGFPE exception will crash an application with
a second SIGFPE in the signal handler. Dave analyzed it, and it happens
because glibc uses a double-word floating-point store to atomically update
function descriptors. As a result of lazy binding, we hit a floating-point
store in fpe_func almost immediately.
When the T bit is set, an assist exception trap occurs when when the
co-processor encounters *any* floating-point instruction except for a double
store of register %fr0. The latter cancels all pending traps. Let's fix this
by clearing the Trap (T) bit in the FP status register before returning to the
signal handler in userspace.
The issue can be reproduced with this test program:
root@parisc:~# cat fpe.c
static void fpe_func(int sig, siginfo_t *i, void *v) {
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGFPE);
sigprocmask(SIG_UNBLOCK, &set, NULL);
printf("GOT signal %d with si_code %ld\n", sig, i->si_code);
}
int main() {
struct sigaction action = {
.sa_sigaction = fpe_func,
.sa_flags = SA_RESTART|SA_SIGINFO };
sigaction(SIGFPE, &action, 0);
feenableexcept(FE_OVERFLOW);
return printf("%lf\n",1.7976931348623158E308*1.7976931348623158E308);
}
root@parisc:~# gcc fpe.c -lm
root@parisc:~# ./a.out
Floating point exception
root@parisc:~# strace -f ./a.out
execve("./a.out", ["./a.out"], 0xf9ac7034 /* 20 vars */) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0
...
rt_sigaction(SIGFPE, {sa_handler=0x1110a, sa_mask=[], sa_flags=SA_RESTART|SA_SIGINFO}, NULL, 8) = 0
--- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0x1078f} ---
--- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0xf8f21237} ---
+++ killed by SIGFPE +++
Floating point exception |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcm80211: fmac: Add error handling for brcmf_usb_dl_writeimage()
The function brcmf_usb_dl_writeimage() calls the function
brcmf_usb_dl_cmd() but dose not check its return value. The
'state.state' and the 'state.bytes' are uninitialized if the
function brcmf_usb_dl_cmd() fails. It is dangerous to use
uninitialized variables in the conditions.
Add error handling for brcmf_usb_dl_cmd() to jump to error
handling path if the brcmf_usb_dl_cmd() fails and the
'state.state' and the 'state.bytes' are uninitialized.
Improve the error message to report more detailed error
information. |
| In the Linux kernel, the following vulnerability has been resolved:
net: phy: leds: fix memory leak
A network restart test on a router led to an out-of-memory condition,
which was traced to a memory leak in the PHY LED trigger code.
The root cause is misuse of the devm API. The registration function
(phy_led_triggers_register) is called from phy_attach_direct, not
phy_probe, and the unregister function (phy_led_triggers_unregister)
is called from phy_detach, not phy_remove. This means the register and
unregister functions can be called multiple times for the same PHY
device, but devm-allocated memory is not freed until the driver is
unbound.
This also prevents kmemleak from detecting the leak, as the devm API
internally stores the allocated pointer.
Fix this by replacing devm_kzalloc/devm_kcalloc with standard
kzalloc/kcalloc, and add the corresponding kfree calls in the unregister
path. |
| In the Linux kernel, the following vulnerability has been resolved:
USB: wdm: close race between wdm_open and wdm_wwan_port_stop
Clearing WDM_WWAN_IN_USE must be the last action or
we can open a chardev whose URBs are still poisoned |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/gt: Fix timeline left held on VMA alloc error
The following error has been reported sporadically by CI when a test
unbinds the i915 driver on a ring submission platform:
<4> [239.330153] ------------[ cut here ]------------
<4> [239.330166] i915 0000:00:02.0: [drm] drm_WARN_ON(dev_priv->mm.shrink_count)
<4> [239.330196] WARNING: CPU: 1 PID: 18570 at drivers/gpu/drm/i915/i915_gem.c:1309 i915_gem_cleanup_early+0x13e/0x150 [i915]
...
<4> [239.330640] RIP: 0010:i915_gem_cleanup_early+0x13e/0x150 [i915]
...
<4> [239.330942] Call Trace:
<4> [239.330944] <TASK>
<4> [239.330949] i915_driver_late_release+0x2b/0xa0 [i915]
<4> [239.331202] i915_driver_release+0x86/0xa0 [i915]
<4> [239.331482] devm_drm_dev_init_release+0x61/0x90
<4> [239.331494] devm_action_release+0x15/0x30
<4> [239.331504] release_nodes+0x3d/0x120
<4> [239.331517] devres_release_all+0x96/0xd0
<4> [239.331533] device_unbind_cleanup+0x12/0x80
<4> [239.331543] device_release_driver_internal+0x23a/0x280
<4> [239.331550] ? bus_find_device+0xa5/0xe0
<4> [239.331563] device_driver_detach+0x14/0x20
...
<4> [357.719679] ---[ end trace 0000000000000000 ]---
If the test also unloads the i915 module then that's followed with:
<3> [357.787478] =============================================================================
<3> [357.788006] BUG i915_vma (Tainted: G U W N ): Objects remaining on __kmem_cache_shutdown()
<3> [357.788031] -----------------------------------------------------------------------------
<3> [357.788204] Object 0xffff888109e7f480 @offset=29824
<3> [357.788670] Allocated in i915_vma_instance+0xee/0xc10 [i915] age=292729 cpu=4 pid=2244
<4> [357.788994] i915_vma_instance+0xee/0xc10 [i915]
<4> [357.789290] init_status_page+0x7b/0x420 [i915]
<4> [357.789532] intel_engines_init+0x1d8/0x980 [i915]
<4> [357.789772] intel_gt_init+0x175/0x450 [i915]
<4> [357.790014] i915_gem_init+0x113/0x340 [i915]
<4> [357.790281] i915_driver_probe+0x847/0xed0 [i915]
<4> [357.790504] i915_pci_probe+0xe6/0x220 [i915]
...
Closer analysis of CI results history has revealed a dependency of the
error on a few IGT tests, namely:
- igt@api_intel_allocator@fork-simple-stress-signal,
- igt@api_intel_allocator@two-level-inception-interruptible,
- igt@gem_linear_blits@interruptible,
- igt@prime_mmap_coherency@ioctl-errors,
which invisibly trigger the issue, then exhibited with first driver unbind
attempt.
All of the above tests perform actions which are actively interrupted with
signals. Further debugging has allowed to narrow that scope down to
DRM_IOCTL_I915_GEM_EXECBUFFER2, and ring_context_alloc(), specific to ring
submission, in particular.
If successful then that function, or its execlists or GuC submission
equivalent, is supposed to be called only once per GEM context engine,
followed by raise of a flag that prevents the function from being called
again. The function is expected to unwind its internal errors itself, so
it may be safely called once more after it returns an error.
In case of ring submission, the function first gets a reference to the
engine's legacy timeline and then allocates a VMA. If the VMA allocation
fails, e.g. when i915_vma_instance() called from inside is interrupted
with a signal, then ring_context_alloc() fails, leaving the timeline held
referenced. On next I915_GEM_EXECBUFFER2 IOCTL, another reference to the
timeline is got, and only that last one is put on successful completion.
As a consequence, the legacy timeline, with its underlying engine status
page's VMA object, is still held and not released on driver unbind.
Get the legacy timeline only after successful allocation of the context
engine's VMA.
v2: Add a note on other submission methods (Krzysztof Karas):
Both execlists and GuC submission use lrc_alloc() which seems free
from a similar issue.
(cherry picked from commit cc43422b3cc79eacff4c5a8ba0d224688ca9dd4f) |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx5: Initialize obj_event->obj_sub_list before xa_insert
The obj_event may be loaded immediately after inserted, then if the
list_head is not initialized then we may get a poisonous pointer. This
fixes the crash below:
mlx5_core 0000:03:00.0: MLX5E: StrdRq(1) RqSz(8) StrdSz(2048) RxCqeCmprss(0 enhanced)
mlx5_core.sf mlx5_core.sf.4: firmware version: 32.38.3056
mlx5_core 0000:03:00.0 en3f0pf0sf2002: renamed from eth0
mlx5_core.sf mlx5_core.sf.4: Rate limit: 127 rates are supported, range: 0Mbps to 195312Mbps
IPv6: ADDRCONF(NETDEV_CHANGE): en3f0pf0sf2002: link becomes ready
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060
Mem abort info:
ESR = 0x96000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=00000007760fb000
[0000000000000060] pgd=000000076f6d7003, p4d=000000076f6d7003, pud=0000000777841003, pmd=0000000000000000
Internal error: Oops: 96000006 [#1] SMP
Modules linked in: ipmb_host(OE) act_mirred(E) cls_flower(E) sch_ingress(E) mptcp_diag(E) udp_diag(E) raw_diag(E) unix_diag(E) tcp_diag(E) inet_diag(E) binfmt_misc(E) bonding(OE) rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) isofs(E) cdrom(E) mst_pciconf(OE) ib_umad(OE) mlx5_ib(OE) ipmb_dev_int(OE) mlx5_core(OE) kpatch_15237886(OEK) mlxdevm(OE) auxiliary(OE) ib_uverbs(OE) ib_core(OE) psample(E) mlxfw(OE) tls(E) sunrpc(E) vfat(E) fat(E) crct10dif_ce(E) ghash_ce(E) sha1_ce(E) sbsa_gwdt(E) virtio_console(E) ext4(E) mbcache(E) jbd2(E) xfs(E) libcrc32c(E) mmc_block(E) virtio_net(E) net_failover(E) failover(E) sha2_ce(E) sha256_arm64(E) nvme(OE) nvme_core(OE) gpio_mlxbf3(OE) mlx_compat(OE) mlxbf_pmc(OE) i2c_mlxbf(OE) sdhci_of_dwcmshc(OE) pinctrl_mlxbf3(OE) mlxbf_pka(OE) gpio_generic(E) i2c_core(E) mmc_core(E) mlxbf_gige(OE) vitesse(E) pwr_mlxbf(OE) mlxbf_tmfifo(OE) micrel(E) mlxbf_bootctl(OE) virtio_ring(E) virtio(E) ipmi_devintf(E) ipmi_msghandler(E)
[last unloaded: mst_pci]
CPU: 11 PID: 20913 Comm: rte-worker-11 Kdump: loaded Tainted: G OE K 5.10.134-13.1.an8.aarch64 #1
Hardware name: https://www.mellanox.com BlueField-3 SmartNIC Main Card/BlueField-3 SmartNIC Main Card, BIOS 4.2.2.12968 Oct 26 2023
pstate: a0400089 (NzCv daIf +PAN -UAO -TCO BTYPE=--)
pc : dispatch_event_fd+0x68/0x300 [mlx5_ib]
lr : devx_event_notifier+0xcc/0x228 [mlx5_ib]
sp : ffff80001005bcf0
x29: ffff80001005bcf0 x28: 0000000000000001
x27: ffff244e0740a1d8 x26: ffff244e0740a1d0
x25: ffffda56beff5ae0 x24: ffffda56bf911618
x23: ffff244e0596a480 x22: ffff244e0596a480
x21: ffff244d8312ad90 x20: ffff244e0596a480
x19: fffffffffffffff0 x18: 0000000000000000
x17: 0000000000000000 x16: ffffda56be66d620
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000040 x10: ffffda56bfcafb50
x9 : ffffda5655c25f2c x8 : 0000000000000010
x7 : 0000000000000000 x6 : ffff24545a2e24b8
x5 : 0000000000000003 x4 : ffff80001005bd28
x3 : 0000000000000000 x2 : 0000000000000000
x1 : ffff244e0596a480 x0 : ffff244d8312ad90
Call trace:
dispatch_event_fd+0x68/0x300 [mlx5_ib]
devx_event_notifier+0xcc/0x228 [mlx5_ib]
atomic_notifier_call_chain+0x58/0x80
mlx5_eq_async_int+0x148/0x2b0 [mlx5_core]
atomic_notifier_call_chain+0x58/0x80
irq_int_handler+0x20/0x30 [mlx5_core]
__handle_irq_event_percpu+0x60/0x220
handle_irq_event_percpu+0x3c/0x90
handle_irq_event+0x58/0x158
handle_fasteoi_irq+0xfc/0x188
generic_handle_irq+0x34/0x48
... |
| In the Linux kernel, the following vulnerability has been resolved:
ACPICA: Refuse to evaluate a method if arguments are missing
As reported in [1], a platform firmware update that increased the number
of method parameters and forgot to update a least one of its callers,
caused ACPICA to crash due to use-after-free.
Since this a result of a clear AML issue that arguably cannot be fixed
up by the interpreter (it cannot produce missing data out of thin air),
address it by making ACPICA refuse to evaluate a method if the caller
attempts to pass fewer arguments than expected to it. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: lan78xx: fix WARN in __netif_napi_del_locked on disconnect
Remove redundant netif_napi_del() call from disconnect path.
A WARN may be triggered in __netif_napi_del_locked() during USB device
disconnect:
WARNING: CPU: 0 PID: 11 at net/core/dev.c:7417 __netif_napi_del_locked+0x2b4/0x350
This happens because netif_napi_del() is called in the disconnect path while
NAPI is still enabled. However, it is not necessary to call netif_napi_del()
explicitly, since unregister_netdev() will handle NAPI teardown automatically
and safely. Removing the redundant call avoids triggering the warning.
Full trace:
lan78xx 1-1:1.0 enu1: Failed to read register index 0x000000c4. ret = -ENODEV
lan78xx 1-1:1.0 enu1: Failed to set MAC down with error -ENODEV
lan78xx 1-1:1.0 enu1: Link is Down
lan78xx 1-1:1.0 enu1: Failed to read register index 0x00000120. ret = -ENODEV
------------[ cut here ]------------
WARNING: CPU: 0 PID: 11 at net/core/dev.c:7417 __netif_napi_del_locked+0x2b4/0x350
Modules linked in: flexcan can_dev fuse
CPU: 0 UID: 0 PID: 11 Comm: kworker/0:1 Not tainted 6.16.0-rc2-00624-ge926949dab03 #9 PREEMPT
Hardware name: SKOV IMX8MP CPU revC - bd500 (DT)
Workqueue: usb_hub_wq hub_event
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __netif_napi_del_locked+0x2b4/0x350
lr : __netif_napi_del_locked+0x7c/0x350
sp : ffffffc085b673c0
x29: ffffffc085b673c0 x28: ffffff800b7f2000 x27: ffffff800b7f20d8
x26: ffffff80110bcf58 x25: ffffff80110bd978 x24: 1ffffff0022179eb
x23: ffffff80110bc000 x22: ffffff800b7f5000 x21: ffffff80110bc000
x20: ffffff80110bcf38 x19: ffffff80110bcf28 x18: dfffffc000000000
x17: ffffffc081578940 x16: ffffffc08284cee0 x15: 0000000000000028
x14: 0000000000000006 x13: 0000000000040000 x12: ffffffb0022179e8
x11: 1ffffff0022179e7 x10: ffffffb0022179e7 x9 : dfffffc000000000
x8 : 0000004ffdde8619 x7 : ffffff80110bcf3f x6 : 0000000000000001
x5 : ffffff80110bcf38 x4 : ffffff80110bcf38 x3 : 0000000000000000
x2 : 0000000000000000 x1 : 1ffffff0022179e7 x0 : 0000000000000000
Call trace:
__netif_napi_del_locked+0x2b4/0x350 (P)
lan78xx_disconnect+0xf4/0x360
usb_unbind_interface+0x158/0x718
device_remove+0x100/0x150
device_release_driver_internal+0x308/0x478
device_release_driver+0x1c/0x30
bus_remove_device+0x1a8/0x368
device_del+0x2e0/0x7b0
usb_disable_device+0x244/0x540
usb_disconnect+0x220/0x758
hub_event+0x105c/0x35e0
process_one_work+0x760/0x17b0
worker_thread+0x768/0xce8
kthread+0x3bc/0x690
ret_from_fork+0x10/0x20
irq event stamp: 211604
hardirqs last enabled at (211603): [<ffffffc0828cc9ec>] _raw_spin_unlock_irqrestore+0x84/0x98
hardirqs last disabled at (211604): [<ffffffc0828a9a84>] el1_dbg+0x24/0x80
softirqs last enabled at (211296): [<ffffffc080095f10>] handle_softirqs+0x820/0xbc8
softirqs last disabled at (210993): [<ffffffc080010288>] __do_softirq+0x18/0x20
---[ end trace 0000000000000000 ]---
lan78xx 1-1:1.0 enu1: failed to kill vid 0081/0 |
| In the Linux kernel, the following vulnerability has been resolved:
mtd: spinand: fix memory leak of ECC engine conf
Memory allocated for the ECC engine conf is not released during spinand
cleanup. Below kmemleak trace is seen for this memory leak:
unreferenced object 0xffffff80064f00e0 (size 8):
comm "swapper/0", pid 1, jiffies 4294937458
hex dump (first 8 bytes):
00 00 00 00 00 00 00 00 ........
backtrace (crc 0):
kmemleak_alloc+0x30/0x40
__kmalloc_cache_noprof+0x208/0x3c0
spinand_ondie_ecc_init_ctx+0x114/0x200
nand_ecc_init_ctx+0x70/0xa8
nanddev_ecc_engine_init+0xec/0x27c
spinand_probe+0xa2c/0x1620
spi_mem_probe+0x130/0x21c
spi_probe+0xf0/0x170
really_probe+0x17c/0x6e8
__driver_probe_device+0x17c/0x21c
driver_probe_device+0x58/0x180
__device_attach_driver+0x15c/0x1f8
bus_for_each_drv+0xec/0x150
__device_attach+0x188/0x24c
device_initial_probe+0x10/0x20
bus_probe_device+0x11c/0x160
Fix the leak by calling nanddev_ecc_engine_cleanup() inside
spinand_cleanup(). |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix iteration of extrefs during log replay
At __inode_add_ref() when processing extrefs, if we jump into the next
label we have an undefined value of victim_name.len, since we haven't
initialized it before we did the goto. This results in an invalid memory
access in the next iteration of the loop since victim_name.len was not
initialized to the length of the name of the current extref.
Fix this by initializing victim_name.len with the current extref's name
length. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/aio: Check IOCB_AIO_RW before the struct aio_kiocb conversion
The first kiocb_set_cancel_fn() argument may point at a struct kiocb
that is not embedded inside struct aio_kiocb. With the current code,
depending on the compiler, the req->ki_ctx read happens either before
the IOCB_AIO_RW test or after that test. Move the req->ki_ctx read such
that it is guaranteed that the IOCB_AIO_RW test happens first. |
| In the Linux kernel, the following vulnerability has been resolved:
mmc: core: Avoid negative index with array access
Commit 4d0c8d0aef63 ("mmc: core: Use mrq.sbc in close-ended ffu") assigns
prev_idata = idatas[i - 1], but doesn't check that the iterator i is
greater than zero. Let's fix this by adding a check. |
| In the Linux kernel, the following vulnerability has been resolved:
jffs2: check jffs2_prealloc_raw_node_refs() result in few other places
Fuzzing hit another invalid pointer dereference due to the lack of
checking whether jffs2_prealloc_raw_node_refs() completed successfully.
Subsequent logic implies that the node refs have been allocated.
Handle that. The code is ready for propagating the error upwards.
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 5835 Comm: syz-executor145 Not tainted 5.10.234-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:jffs2_link_node_ref+0xac/0x690 fs/jffs2/nodelist.c:600
Call Trace:
jffs2_mark_erased_block fs/jffs2/erase.c:460 [inline]
jffs2_erase_pending_blocks+0x688/0x1860 fs/jffs2/erase.c:118
jffs2_garbage_collect_pass+0x638/0x1a00 fs/jffs2/gc.c:253
jffs2_reserve_space+0x3f4/0xad0 fs/jffs2/nodemgmt.c:167
jffs2_write_inode_range+0x246/0xb50 fs/jffs2/write.c:362
jffs2_write_end+0x712/0x1110 fs/jffs2/file.c:302
generic_perform_write+0x2c2/0x500 mm/filemap.c:3347
__generic_file_write_iter+0x252/0x610 mm/filemap.c:3465
generic_file_write_iter+0xdb/0x230 mm/filemap.c:3497
call_write_iter include/linux/fs.h:2039 [inline]
do_iter_readv_writev+0x46d/0x750 fs/read_write.c:740
do_iter_write+0x18c/0x710 fs/read_write.c:866
vfs_writev+0x1db/0x6a0 fs/read_write.c:939
do_pwritev fs/read_write.c:1036 [inline]
__do_sys_pwritev fs/read_write.c:1083 [inline]
__se_sys_pwritev fs/read_write.c:1078 [inline]
__x64_sys_pwritev+0x235/0x310 fs/read_write.c:1078
do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
Found by Linux Verification Center (linuxtesting.org) with Syzkaller. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/sgx: Prevent attempts to reclaim poisoned pages
TL;DR: SGX page reclaim touches the page to copy its contents to
secondary storage. SGX instructions do not gracefully handle machine
checks. Despite this, the existing SGX code will try to reclaim pages
that it _knows_ are poisoned. Avoid even trying to reclaim poisoned pages.
The longer story:
Pages used by an enclave only get epc_page->poison set in
arch_memory_failure() but they currently stay on sgx_active_page_list until
sgx_encl_release(), with the SGX_EPC_PAGE_RECLAIMER_TRACKED flag untouched.
epc_page->poison is not checked in the reclaimer logic meaning that, if other
conditions are met, an attempt will be made to reclaim an EPC page that was
poisoned. This is bad because 1. we don't want that page to end up added
to another enclave and 2. it is likely to cause one core to shut down
and the kernel to panic.
Specifically, reclaiming uses microcode operations including "EWB" which
accesses the EPC page contents to encrypt and write them out to non-SGX
memory. Those operations cannot handle MCEs in their accesses other than
by putting the executing core into a special shutdown state (affecting
both threads with HT.) The kernel will subsequently panic on the
remaining cores seeing the core didn't enter MCE handler(s) in time.
Call sgx_unmark_page_reclaimable() to remove the affected EPC page from
sgx_active_page_list on memory error to stop it being considered for
reclaiming.
Testing epc_page->poison in sgx_reclaim_pages() would also work but I assume
it's better to add code in the less likely paths.
The affected EPC page is not added to &node->sgx_poison_page_list until
later in sgx_encl_release()->sgx_free_epc_page() when it is EREMOVEd.
Membership on other lists doesn't change to avoid changing any of the
lists' semantics except for sgx_active_page_list. There's a "TBD" comment
in arch_memory_failure() about pre-emptive actions, the goal here is not
to address everything that it may imply.
This also doesn't completely close the time window when a memory error
notification will be fatal (for a not previously poisoned EPC page) --
the MCE can happen after sgx_reclaim_pages() has selected its candidates
or even *inside* a microcode operation (actually easy to trigger due to
the amount of time spent in them.)
The spinlock in sgx_unmark_page_reclaimable() is safe because
memory_failure() runs in process context and no spinlocks are held,
explicitly noted in a mm/memory-failure.c comment. |
| In the Linux kernel, the following vulnerability has been resolved:
Input: gpio-keys - fix a sleep while atomic with PREEMPT_RT
When enabling PREEMPT_RT, the gpio_keys_irq_timer() callback runs in
hard irq context, but the input_event() takes a spin_lock, which isn't
allowed there as it is converted to a rt_spin_lock().
[ 4054.289999] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
[ 4054.290028] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/0
...
[ 4054.290195] __might_resched+0x13c/0x1f4
[ 4054.290209] rt_spin_lock+0x54/0x11c
[ 4054.290219] input_event+0x48/0x80
[ 4054.290230] gpio_keys_irq_timer+0x4c/0x78
[ 4054.290243] __hrtimer_run_queues+0x1a4/0x438
[ 4054.290257] hrtimer_interrupt+0xe4/0x240
[ 4054.290269] arch_timer_handler_phys+0x2c/0x44
[ 4054.290283] handle_percpu_devid_irq+0x8c/0x14c
[ 4054.290297] handle_irq_desc+0x40/0x58
[ 4054.290307] generic_handle_domain_irq+0x1c/0x28
[ 4054.290316] gic_handle_irq+0x44/0xcc
Considering the gpio_keys_irq_isr() can run in any context, e.g. it can
be threaded, it seems there's no point in requesting the timer isr to
run in hard irq context.
Relax the hrtimer not to use the hard context. |
