ffs_epfile_dmabuf_io_complete() calls usb_ep_free_request() on the
completed request but leaves priv->req, the back-pointer that
ffs_dmabuf_transfer() set on submission, pointing at the freed
memory. A later FUNCTIONFS_DMABUF_DETACH ioctl or
ffs_epfile_release() on the close path still sees priv->req
non-NULL under ffs->eps_lock:
if (priv->ep && priv->req)
usb_ep_dequeue(priv->ep, priv->req);
so usb_ep_dequeue() is called on a freed usb_request.
On dummy_hcd the dequeue path only walks a live queue and
pointer-compares, so the freed pointer reads without faulting and
KASAN requires an explicit check at the FunctionFS call site to
surface the use-after-free. On SG-capable in-tree UDCs the
dequeue path dereferences the supplied request immediately:
* chipidea's ep_dequeue() does
container_of(req, struct ci_hw_req, req) and reads
hwreq->req.status before acquiring its own lock.
* cdnsp's cdnsp_gadget_ep_dequeue() reads request->status first.
The narrower option of clearing priv->req via cmpxchg() in the
completion does not close the race: the completion runs without
eps_lock, so a cancel path holding eps_lock can still observe
priv->req non-NULL, race a concurrent completion that clears and
frees, and pass the freed pointer to usb_ep_dequeue(). A slightly
longer fix that moves the free into the cleanup work is needed.
Same class of lifetime race as the recent usbip-vudc timer fix [1].
Take eps_lock in the sole place that mutates priv->req from the
callback direction by moving usb_ep_free_request() out of the
completion into ffs_dmabuf_cleanup(), the existing work handler
scheduled by ffs_dmabuf_signal_done() on
ffs->io_completion_wq. Clear priv->req there under eps_lock
before freeing, and only clear if priv->req still names our
request (a subsequent ffs_dmabuf_transfer() on the same
attachment may have queued a new one).
This keeps the existing dummy_hcd sync-dequeue invariant: the
completion callback is still invoked by the UDC without
eps_lock held (dummy_hcd drops its own lock before calling the
callback), and the callback now takes no f_fs lock at all.
Serialization against the cancel path happens in cleanup, which
runs from the workqueue with no f_fs lock held on entry.
The priv ref count protects the containing ffs_dmabuf_priv:
ffs_dmabuf_transfer() takes a ref via ffs_dmabuf_get(), cleanup
drops it via ffs_dmabuf_put(), so priv stays live for the
cleanup even after the cancel path's list_del + ffs_dmabuf_put.
The ffs_dmabuf_transfer() error path no longer frees usb_req
inline: fence->req and fence->ep are set before usb_ep_queue(),
so ffs_dmabuf_cleanup() (scheduled by the error-path
ffs_dmabuf_signal_done()) owns the free regardless of whether
the queue succeeded.
Reproduced under KASAN on both detach and close paths against
dummy_hcd with an observability hook
(kasan_check_byte(priv->req) immediately before usb_ep_dequeue)
at the two FunctionFS cancel sites to surface the stale-pointer
access; the hook is not part of this patch. The KASAN
allocator / free stacks in the captured splats identify the
same request: alloc in dummy_alloc_request, free in
dummy_timer, fault reached from ffs_epfile_release (close) and
from the FUNCTIONFS_DMABUF_DETACH ioctl (detach). With the
patch applied, both paths are silent under the same hook.
The bug is reached from the FunctionFS device node, which in
real deployments is owned by the privileged gadget daemon
(adbd, UMS, composite gadget services, etc.); it is not
reachable from unprivileged userspace or from a USB host on the
cable. FunctionFS mounts default to GLOBAL_ROOT_UID, but the
filesystem supports uid=, gid=, and fmode= delegation to a
non-root gadget daemon, so on real deployments the attacker may
be a less-privileged service rather than root.
Fixes: 7b07a2a7ca ("usb: gadget: functionfs: Add DMABUF import interface")
Link: https://lore.kernel.org/all/20260417163552.807548-1-michael.bommarito@gmail.com/ [1]
Cc: stable <stable@kernel.org>
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260419161227.1587668-1-michael.bommarito@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ffs_ep0_read() allocates its control-OUT data buffer with
kmalloc() (not kzalloc) at the Length value from the Setup
packet, then copies that full len to userspace regardless of
how many bytes were actually received:
data = kmalloc(len, GFP_KERNEL);
...
ret = __ffs_ep0_queue_wait(ffs, data, len);
if ((ret > 0) && (copy_to_user(buf, data, len)))
ret = -EFAULT;
__ffs_ep0_queue_wait() returns req->actual, which on a short
control OUT transfer is strictly less than len. The
copy_to_user() call still copies len bytes, so on a short OUT
the last (len - ret) bytes of the kmalloc() buffer --
uninitialised slab residue -- are delivered to the FunctionFS
daemon.
Short ep0 OUT completions are specified USB control-transfer
behavior and are produced by in-tree UDCs:
* dwc2 continues on req->actual < req->length for ep0 DATA OUT
(short-not-ok is the only ep0-OUT stall path).
* aspeed_udc ends ep0 OUT on rx_len < ep->ep.maxpacket.
* renesas_usbf logs "ep0 short packet" and completes the
request.
* dwc3 stalls on short IN but not on short OUT.
A short ep0 OUT is therefore not evidence of a broken UDC; it is
a normal condition f_fs has to cope with. The sibling gadgetfs
implementation in drivers/usb/gadget/legacy/inode.c already does
this correctly via min(len, dev->req->actual) before
copy_to_user(). This patch brings f_fs.c to the same safe
pattern rather than trimming at a defensive layer.
The bug is reached from the FunctionFS device node, which in
real deployments is owned by the privileged gadget daemon
(adbd, UMS, composite gadget services, etc.); it is not
reachable from unprivileged userspace. Linux host stacks
normally reject short-wLength control OUTs before they reach
the gadget, so reproducing this required a build that
bypasses that host-side check. With the bypass in place, a
1-byte payload on a 64-byte Setup produces 63 bytes of
non-canary slab residue in the daemon's read buffer.
Fix by copying only ret (actually received) bytes to
userspace.
Fixes: ddf8abd259 ("USB: f_fs: the FunctionFS driver")
Cc: stable <stable@kernel.org>
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260419160359.1577270-1-michael.bommarito@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The `dummy_hub_control()` function handles USB hub class requests
to the virtual root hub. The `GetPortStatus` case returns -EPIPE for
requests with `wIndex != 1`, since the virtual root hub has only a
single port. However, the `ClearPortFeature` and `SetPortFeature`
cases lack the same check.
Fix this by extending the `wIndex != 1` rejection to both cases,
matching the existing behavior of `GetPortStatus`.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@kernel.org>
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Seungjin Bae <eeodqql09@gmail.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://patch.msgid.link/20260518234314.1889396-1-eeodqql09@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The EIC7700 USB requires a USB PHY reset operation; otherwise, the USB
will not work. The reason why the USB driver that was applied can work
properly is that the USB PHY has already been reset in ESWIN's U-Boot.
However, the proper functioning of the USB driver should not be dependent
on the bootloader. Therefore, it is necessary to incorporate the USB PHY
reset signal into the DT bindings.
This patch does not introduce any backward incompatibility since the dts
is not upstream yet. As array of reset operations are used in the driver,
no modifications to the USB controller driver are needed.
Fixes: c640a4239d ("dt-bindings: usb: Add ESWIN EIC7700 USB controller")
Cc: stable <stable@kernel.org>
Signed-off-by: Hang Cao <caohang@eswincomputing.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260415064238.1784-1-caohang@eswincomputing.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch follows up Zheng Wang's 2023 report of a use-after-free in
vudc_remove(). The original thread stalled on Shuah Khan's request for
runtime testing of the unplug/unbind path. This patch supplies that
testing and keeps Zheng's original fix shape.
In vudc_probe(), v_init_timer() binds udc->tr_timer.timer to v_timer().
usbip_sockfd_store() starts the timer via v_start_timer()/v_kick_timer().
vudc_remove() can then free the containing struct vudc while the timer is
still pending or executing.
KASAN confirms the race on an unpatched x86_64 QEMU guest with
CONFIG_KASAN=y, CONFIG_USBIP_VUDC=y, CONFIG_USB_ZERO=y, and a tight loop
that repeatedly writes a socket fd to usbip_sockfd, closes the socket
pair, and unbinds/rebinds usbip-vudc.0:
BUG: KASAN: slab-use-after-free in __run_timer_base.part.0+0x8ba/0x8e0
Write of size 8 at addr ffff888001b80740 by task trigger_and_unb/239
Allocated by task 239:
vudc_probe+0x4d/0xaa0
Freed by task 239:
kfree+0x18f/0x520
device_release_driver_internal+0x388/0x540
unbind_store+0xd9/0x100
This lands in the timer core rather than v_timer() itself because the
embedded timer_list is being walked after its containing struct vudc has
already been freed. The underlying lifetime bug is the same one Zheng
reported.
With v_stop_timer() called from vudc_remove() and the timer deleted
synchronously, the same harness completed 5000 bind/unbind iterations
with no KASAN report.
Fixes: b6a0ca1118 ("usbip: vudc: Add UDC specific ops")
Cc: stable <stable@kernel.org>
Reported-by: Zheng Wang <zyytlz.wz@163.com>
Closes: https://lore.kernel.org/linux-usb/20230317100954.2626573-1-zyytlz.wz@163.com/
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://patch.msgid.link/20260417163552.807548-1-michael.bommarito@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The deprecated 'usb-phy' property is documented already in usb.yaml and
doesn't need a type definition here. It just needs constraints on how
many entries there are.
As this is a host controller, reference usb-hcd.yaml which then
references usb.yaml.
Fixes: 70fcdc82cf ("dt-bindings: usb: ti,omap4-musb: convert to DT schema")
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20260508182556.1759173-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The PNY Elite Portable SSD (USB ID 154b:f009) is a sibling of the
already-quirked PNY Pro Elite SSDs (154b:f00b and 154b:f00d). Like its
siblings, it uses a Phison-based USB-SATA bridge that exhibits
firmware bugs when bound to the uas driver.
Without quirks, the device fails to complete READ CAPACITY commands
when accessed over UAS on a SuperSpeed (USB 3) port. The device
enumerates and reports as a SCSI direct-access device, but reports
zero logical blocks and never finishes spin-up:
usb 2-3: new SuperSpeed USB device number 8 using xhci_hcd
usb 2-3: New USB device found, idVendor=154b, idProduct=f009
usb 2-3: Product: PNY ELITE PSSD
usb 2-3: Manufacturer: PNY
scsi host0: uas
scsi 0:0:0:0: Direct-Access PNY PNY ELITE PSSD 0
sd 0:0:0:0: [sda] Spinning up disk...
[...10+ seconds of polling, no progress...]
sd 0:0:0:0: [sda] Read Capacity(16) failed: hostbyte=DID_ERROR
sd 0:0:0:0: [sda] Read Capacity(10) failed: hostbyte=DID_ERROR
sd 0:0:0:0: [sda] 0 512-byte logical blocks: (0 B/0 B)
Tested each individual quirk to find the minimum that fixes this:
- US_FL_NO_ATA_1X alone: device hangs on spin-up
- US_FL_NO_REPORT_OPCODES alone: works on USB 2.0, hangs on USB 3.0
- US_FL_NO_ATA_1X | US_FL_NO_REPORT_OPCODES: works on both
With both quirks the device enumerates correctly while still using
the uas driver, and delivers full UAS throughput (~281 MB/s
sequential read on a USB 3.0 Gen 1 port).
The existing PNY Pro Elite entries (f00b, f00d) only set NO_ATA_1X,
but this device additionally chokes on REPORT OPCODES under
SuperSpeed.
Signed-off-by: Sam Burkels <sam@1a38.nl>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@kernel.org>
Link: https://patch.msgid.link/20260501132346.86572-1-sam@1a38.nl
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Lenovo ThinkPad USB-C Dock Gen2 (17ef:a391, 17ef:a392) hub
controllers exhibit link instability when USB Link Power Management
is enabled, similar to the dock's Ethernet adapter (17ef:a387) which
already carries USB_QUIRK_NO_LPM.
When the dock reconnects after a transient disconnect, the hub
controllers enter LPM states between re-enumeration retries, causing
repeated disconnect/reconnect cycles lasting up to two minutes.
Disabling LPM for these devices restores stable enumeration.
Signed-off-by: Stephen J. Fuhry <fuhrysteve@gmail.com>
Cc: stable <stable@kernel.org>
Link: https://patch.msgid.link/20260513171419.44849-1-fuhrysteve@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The USB488 subclass specification requires interrupt wMaxPacketSize to
be 0x02, unless the device sends vendor-specific notifications.
Endpoints that advertise less than 2 bytes for wMaxPacketSize are
unlikely to work with the current driver, as URBs will not have enough
space for interrupt headers. Considering that any notification URBs will
be ignored by the driver, reject these endpoints early during probe.
Fixes: 041370cce8 ("USB: usbtmc: refactor endpoint retrieval")
Cc: stable <stable@kernel.org>
Suggested-by: Michal Pecio <michal.pecio@gmail.com>
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Link: https://patch.msgid.link/20260505-usbtmc-iin-size-v3-2-a36113f62db7@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USBTMC devices can use an optional interrupt endpoint for notification
messages. These typically contain two-byte headers indicating the
payload format, but the driver does not check if these headers are
present before accessing the data buffers. In cases where the URB
actual_length is not enough to fit these headers, the driver will either
cause an out-of-bounds read, or consume stale leftover data from a
previous notification.
Fix by checking if actual_data contains enough bytes for the headers,
otherwise resubmit URB to the interrupt endpoint.
Fixes: dbf3e7f654 ("Implement an ioctl to support the USMTMC-USB488 READ_STATUS_BYTE operation.")
Reported-by: syzbot+abbfd103085885cf16a2@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=abbfd103085885cf16a2
Cc: stable <stable@kernel.org>
Suggested-by: Michal Pecio <michal.pecio@gmail.com>
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Link: https://patch.msgid.link/20260505-usbtmc-iin-size-v3-1-a36113f62db7@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a USB device is unplugged from the dual-role port, the device-mode
path in tegra_xhci_id_work() explicitly clears both SS and HS port power
via direct hub_control ClearPortFeature(POWER) calls. This preempts the
xHCI controller's normal disconnect processing -- PORT_CSC is never
generated, the USB core never sees the disconnect, and the device remains
in its internal tree as a ghost visible in lsusb.
Add an otg_set_port_power flag to control whether the dual-role switch
path performs explicit port power management. SoCs that need it
(Tegra124 / Tegra210 / Tegra186) set the flag; later SoCs (Tegra194 and
beyond) rely on the PHY mode change to handle disconnect naturally and
skip all port power calls.
Within the port power path, otg_reset_sspi additionally gates the SSPI
reset sequence on host-mode entry for SoCs that require it.
Flags set per SoC:
Tegra124, Tegra186 -> otg_set_port_power
Tegra210 -> otg_set_port_power, otg_reset_sspi
Tegra194 and later -> (none)
Fixes: f836e78430 ("usb: xhci-tegra: Add OTG support")
Cc: stable <stable@kernel.org>
Signed-off-by: Wei-Cheng Chen <weichengc@nvidia.com>
Link: https://patch.msgid.link/20260505112630.217704-1-weichengc@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uvc_function_bind() walks &opts->extension_units twice without holding
opts->lock:
- directly, for the iExtension string-descriptor fixup loop;
- indirectly, four times via uvc_copy_descriptors() (once per speed),
where the helper iterates uvc->desc.extension_units (which aliases
&opts->extension_units) to size and emit XU descriptors.
The configfs side (uvcg_extension_make / uvcg_extension_drop, in
drivers/usb/gadget/function/uvc_configfs.c) takes opts->lock around its
list_add_tail / list_del operations. A privileged userspace process
that holds the configfs subtree open and writes the gadget UDC name
to bind the function while concurrently rmdir()'ing an extensions
subdir can race uvcg_extension_drop() against the bind-time list walks
and dereference a freed struct uvcg_extension.
Hold opts->lock from the start of the XU string-descriptor fixup
through the last uvc_copy_descriptors() call, releasing on the
descriptor-error path via a new error_unlock label that drops the
lock before falling through to the existing error label. This
matches the locking discipline of the configfs callbacks and removes
the only remaining unsynchronised reader of the XU list during bind.
Reachability: only privileged processes that can mount configfs and
write to gadget UDC files can trigger the race, so this is a
correctness fix rather than a security boundary.
Fixes: 0525210c98 ("usb: gadget: uvc: Allow definition of XUs in configfs")
Cc: stable <stable@kernel.org>
Signed-off-by: Kai Aizen <kai.aizen.dev@gmail.com>
Link: https://patch.msgid.link/20260430175643.67120-1-kai.aizen.dev@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb_initialize_gadget() installs gadget_release() as the release
callback for the embedded gadget device. The struct net2280 instance is
therefore released through gadget_release() when the gadget device's last
reference is dropped.
The probe error path calls net2280_remove(), which tears down the
partially initialized device and drops the gadget reference with
usb_put_gadget(). Calling kfree(dev) afterwards can free the same object
again.
Drop the explicit kfree() and let the gadget device release callback
handle the final free. This issue was found by a static analysis tool
I am developing.
Fixes: f770fbec41 ("USB: UDC: net2280: Fix memory leaks")
Cc: stable <stable@kernel.org>
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://patch.msgid.link/20260427153651.337846-1-lgs201920130244@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hidg_alloc() initializes hidg->dev with device_initialize() before
calling dev_set_name(). If dev_set_name() fails, the function currently
jumps to err_unlock and returns without calling put_device().
This leaves the device reference unbalanced and prevents hidg_release()
from being called. Calling put_device() here is also safe, since
hidg_release() only frees resources owned by hidg.
The issue was identified by a static analysis tool I developed and
confirmed by manual review.
Route the dev_set_name() failure path through err_put_device so the
device reference is dropped properly.
Fixes: 89ff3dfac6 ("usb: gadget: f_hid: fix f_hidg lifetime vs cdev")
Cc: stable <stable@kernel.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Reviewed-by: Johan Hovold johan@kernel.org
Link: https://patch.msgid.link/20260413142119.2977716-1-lgs201920130244@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In omap2430_probe(), of_node_put(np) is called prematurely before the
last access to np, leading to a use-after-free if the node's reference
count drops to zero. Move the of_node_put() calls after the last use of
np in both the success and error paths.
Fixes: ffbe2feac5 ("usb: musb: omap2430: Fix probe regression for missing resources")
Cc: stable <stable@kernel.org>
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Link: https://patch.msgid.link/20260409101104.480623-1-vulab@iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ESP out-of-place fast path appends the trailer in esp_output_head()
before esp_output_tail() allocates the destination page frag. The
head-side gate currently checks skb->data_len and tailen separately, but
the tail code allocates a single destination frag from the combined
post-trailer skb->data_len.
Reject the page-frag fast path when the combined aligned length exceeds a
page. Otherwise skb_page_frag_refill() may fall back to a single page while
the destination sg still spans the combined skb->data_len.
Restore this combined-length page gate for both IPv4 and IPv6.
Fixes: 5bd8baab08 ("esp: limit skb_page_frag_refill use to a single page")
Cc: stable@vger.kernel.org
Signed-off-by: Lin Ma <malin89@huawei.com>
Signed-off-by: Chenyuan Mi <michenyuan@huawei.com>
Signed-off-by: Jingguo Tan <tanjingguo@huawei.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
In esp_output_tail(), when esp->inplace is false, the old skb page frags
are replaced with a new page from the xfrm page_frag cache. The source
scatterlist (sg) is built from the old frags before the replacement, and
esp_ssg_unref() is responsible for releasing the old page references
after the crypto operation completes.
However, if the second skb_to_sgvec() call (which builds the destination
scatterlist from the new page) fails, the code jumps to error_free which
only calls kfree(tmp). The old page frag references captured in the
source scatterlist are never released:
1. sg[] is built from old frags via skb_to_sgvec() (no extra get_page)
2. nr_frags is set to 1 and frag[0] is replaced with the new page
3. Second skb_to_sgvec() fails -> goto error_free
4. kfree(tmp) frees the sg[] memory but old frags are not unref'd
5. kfree_skb() only releases frag[0] (the new page), not the old ones
Fix this by adding a bool parameter to esp_ssg_unref() that, when true,
unconditionally unrefs the source scatterlist frags without checking
req->src and req->dst, since those fields are not yet initialized by
aead_request_set_crypt() at the point of the error. Existing callers
pass false to preserve the original behavior.
The same issue exists in both esp4 and esp6 as the code is identical.
Fixes: cac2661c53 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Alessandro Schino <7991aleschino@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Some variables relative with paravirt feature are declared in the header
file asm/qspinlock.h, however this file can be included only when option
CONFIG_SMP is on. There is compiling warnings if CONFIG_SMP is off since
variables are not declared.
Move these variable declarations to header file asm/paravirt.h to avoid
compiling warnings.
Fixes: c43dce6f13 ("LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202605061313.O8Hswm2b-lkp@intel.com/
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
KPROBE_HIT_SS and KPROBE_REENTER are two types of fatal recursions that
can not be safely recovered in kprobes.
KPROBE_HIT_SS means that a kprobe is hit during single-stepping. At
this point, the architecture-specific single-step context is already
active. Nested single-stepping would corrupt the state, as the kprobe
control block (kcb) and hardware registers cannot safely store multiple
levels of stepping state.
KPROBE_REENTER means that a third-level recursion occurs when a probe
is hit while the system is already handling a nested probe (second-
level). The kcb only provides a single slot (prev_kprobe) to backup the
state. When a third probe is hit, there is no more space to save the
state without corrupting the first-level backup.
Kprobes work by replacing instructions with breakpoints. In order to
execute the original instruction and continue, it must be moved to a
temporary "single-step" slot. Since there is no backup space left to
set up this slot safely, the CPU would be forced to return to the same
original breakpoint address, triggering an endless loop.
Currently, the code only prints a warning and returns. This leads to
an infinite re-entry loop as the CPU repeatedly hits the same trap and
a "stuck" CPU core because preemption was disabled at the start of the
handler and never re-enabled in this early return path.
Fix the logic by:
1. Merging KPROBE_HIT_SS and KPROBE_REENTER cases, as both represent
fatal recursions that cannot be safely recovered.
2. Replacing WARN_ON_ONCE() with BUG() to terminate the system. This
aligns LoongArch with other architectures (x86, arm64, riscv) and
prevents stack overflow while providing diagnostic information.
Fixes: 6d4cc40fb5 ("LoongArch: Add kprobes support")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
On SMP systems, kprobe handlers would occasionally fail to execute on
certain CPU cores. The issue is hard to reproduce and typically occurs
randomly under high system load.
The root cause is a software-side instruction hazard. According to the
LoongArch Reference Manual, while the cache coherency is maintained by
hardware, software must explicitly use the "IBAR" instruction to ensure
the instruction fetch unit (IFU) observes the effects of recent stores.
The current arch_arm_kprobe() and arch_disarm_kprobe() only execute the
"IBAR" barrier (via flush_insn_slot -> local_flush_icache_range) on the
local CPU. This leaves a vulnerable window where remote CPU cores may
continue executing stale instructions from their pipelines or prefetch
buffers, as they have not executed an "IBAR" since the code modification.
Switch to larch_insn_text_copy() to fix this:
1. Synchronization: It uses stop_machine_cpuslocked() to synchronize all
online CPUs, ensuring no CPU is executing the target code area during
modification.
2. Visibility: By passing cpu_online_mask to stop_machine_cpuslocked(),
the callback text_copy_cb() is executed on all online cores. Each CPU
core invokes local_flush_icache_range() to execute "IBAR", clearing
instruction hazards system-wide and ensuring the "break" instruction
is visible to the fetch units of all cores.
3. Robustness: It properly manages memory write permissions (ROX/RW) for
the kernel text segment during patching, ensuring compatibility with
CONFIG_STRICT_KERNEL_RWX.
Cc: <stable@vger.kernel.org> # 6.18+
Fixes: 6d4cc40fb5 ("LoongArch: Add kprobes support")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
A bigger batch of fixes than usual due to -next not happeing last week,
this is mostly stuff for laptops - a lot of quirks and small fixes,
mainly for x86 and SoundWire. Nothing too big or exciting individually,
just two week's worth.
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Merge tag 'asoc-fix-v7.1-rc4' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v7.1
A bigger batch of fixes than usual due to -next not happeing last week,
this is mostly stuff for laptops - a lot of quirks and small fixes,
mainly for x86 and SoundWire. Nothing too big or exciting individually,
just two week's worth.
This reverts commit db359fccf2 ("mm: introduce a new page type for page
pool in page type") and a part of 735a309b4b ("net: add net_iov_init()
and use it to initialize ->page_type").
Netpp page_type'ed pages might be used in mapping so as to use @_mapcount.
However, since @page_type and @_mapcount are union'ed in struct page,
these two can't be used at the same time. Revert the commit introducing
page_type for Netpp for now.
The patch will be retried once @page_type and @_mapcount get allowed to be
used at the same time.
The revert also includes removal of @page_type initialization part
introduced by commit 735a309b4b ("net: add net_iov_init() and use it
to initialize ->page_type"), which will be restored on the retry.
Link: https://lore.kernel.org/20260515034701.17027-1-byungchul@sk.com
Fixes: db359fccf2 ("mm: introduce a new page type for page pool in page type")
Signed-off-by: Byungchul Park <byungchul@sk.com>
Reported-by: Dragos Tatulea <dtatulea@nvidia.com>
Closes: https://lore.kernel.org/all/982b9bc1-0a0a-4fc5-8e3a-3672db2b29a1@nvidia.com
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Mark Bloch <mbloch@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tariq Toukan <tariqt@nvidia.com>
Cc: Toke Hoiland-Jorgensen <toke@redhat.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__get_vm_area_node() currently triggers a BUG() if in_interrupt() returns
true. However, in_interrupt() also reports true when BH are disabled.
The bridge code can call rhashtable_lookup_insert_fast() with bottom
halves disabled:
__vlan_add()
-> br_fdb_add_local()
spin_lock_bh(&br->hash_lock); <-- Disable BH
-> fdb_add_local()
-> fdb_create()
-> rhashtable_lookup_insert_fast()
-> kvmalloc()
-> vmalloc()
-> __get_vm_area_node()
-> BUG_ON(in_interrupt())
spin_unlock_bh(&br->hash_lock)
this triggers the BUG() despite the caller not being in NMI or
hard IRQ context.
Replace the in_interrupt() check with in_nmi() || in_hardirq().
Link: https://lore.kernel.org/20260515153009.2296191-1-urezki@gmail.com
Fixes: c6307674ed ("mm: kvmalloc: add non-blocking support for vmalloc")
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Ido Schimmel <idosch@nvidia.com>
Reported-by: syzbot+8b12fc6e0fb139765b58@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/69ff8c7c.050a0220.1036b8.000b.GAE@google.com/
Reviewed-by: Baoquan He <baoquan.he@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When migrate_vma_insert_huge_pmd_page() jumps to unlock_abort due
to a PMD check failure, the pgtable allocated earlier via
pte_alloc_one() is never freed, causing a memory leak.
Added free_abort label to release the pgtable in error path.
Link: https://lore.kernel.org/20260501115122.23288-1-nueralspacetech@gmail.com
Fixes: a30b48bf1b ("mm/migrate_device: implement THP migration of zone device pages")
Signed-off-by: Sunny Patel <nueralspacetech@gmail.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Huang Ying <ying.huang@linux.alibaba.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Balbir Singh <balbirs@nvidia.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When a child process exits, it sends exit_signal to its parent via
do_notify_parent(). The clone() syscall constructs exit_signal as:
(lower_32_bits(clone_flags) & CSIGNAL)
CSIGNAL is 0xff, so values in the range 65-255 are possible. However,
valid_signal() only accepts signals up to _NSIG (64 on x86_64). A
non-zero non-valid exit_signal acts the same as exit_signal == 0: the
parent process is not signaled when the child terminates.
The syzkaller reproducer triggers this by calling clone() with flags=0x80,
resulting in exit_signal = (0x80 & CSIGNAL) = 128, which exceeds _NSIG and
is not a valid signal.
The v1 of this patch added the check only in the clone() syscall handler,
which is incomplete. kernel_clone() has other callers such as
sys_ia32_clone() which would remain unprotected. Move the check to
kernel_clone() to cover all callers.
Since the valid_signal() check is now in kernel_clone() and covers all
callers including clone3(), the same check in copy_clone_args_from_user()
becomes redundant and is removed. The higher 32bits check for clone3() is
kept as it is clone3() specific.
Note that this is a user-visible change: previously, passing an invalid
exit_signal to clone() was silently accepted. The man page for clone()
does not document any defined behavior for invalid exit_signal values, so
rejecting them with -EINVAL is the correct behavior. It is unlikely that
any sane application relies on passing an invalid exit_signal.
[oleg@redhat.com: the comment above kernel_clone() should be updated]
Link: https://lore.kernel.org/abwvgU17W8wuW2-J@redhat.com
Link: https://lore.kernel.org/20260316151956.563558-1-kartikey406@gmail.com
Fixes: 3f2c788a13 ("fork: prevent accidental access to clone3 features")
Signed-off-by: Deepanshu Kartikey <Kartikey406@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: syzbot+bbe6b99feefc3a0842de@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=bbe6b99feefc3a0842de
Tested-by: syzbot+bbe6b99feefc3a0842de@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/20260307064202.353405-1-kartikey406@gmail.com/T/ [v1]
Link: https://lore.kernel.org/all/20260316104536.558108-1-kartikey406@gmail.com/T/ [v2]
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
flush_nmi_stats() drains per-node NMI slab atomics into the per-node
lruvec_stats, but does not propagate them to the memcg-level vmstats.
For non NMI case, account_slab_nmi_safe() calls mod_memcg_lruvec_state()
which updates both per-node lruvec_stats and memcg-level vmstats, so
flush_nmi_stats() needs to flush to per-node lruvec_stats as well as
memcg-level vmstats.
So fix this by flushing to the memcg-level vmstats for NMI too.
Link: https://lore.kernel.org/20260518082830.599102-1-alex@ghiti.fr
Fixes: 940b01fc8d ("memcg: nmi safe memcg stats for specific archs")
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON sysfs maintains the DAMOS tried region directory objects via a
linked list. When the user requests refresh of the directories, DAMON
sysfs removes all the region directories first, and then generate updated
regions directory on the empty space. The removal function
(damon_sysfs_scheme_regions_rm_dirs()) only puts the kobj objects.
Deletion of the container region object from the linked list is done
inside the kobj release callback function.
If somehow the callback invocation is delayed, the list will contain
regions list that gonna be freed. If the updated region directories
creation is started in this situation, the list can be corrupted and
use-after-free can happen.
Because the kobj objects are managed by only DAMON sysfs, the issue cannot
happen in normal situation. But, such delays can be made on kernels that
built with CONFIG_DEBUG_KOBJECT_RELEASE. On the kernel, the issue can
indeed be reproduced like below.
# damo start --damos_action stat
# cd /sys/kernel/mm/damon/admin/kdamonds/0/
# for i in {1..10}; do echo update_schemes_tried_regions > state; done
# dmesg | grep underflow
[ 89.296152] refcount_t: underflow; use-after-free.
Fix the issue by removing the region object from the list when
decrementing the reference count.
Also update damos_sysfs_populate_region_dir() to add the region object to
the list only after the kobject_init_and_add() is success, so that fail of
kobject_init_and_add() is not leaving the deallocated object on the list.
The issue was discovered [1] by Sashiko.
Link: https://lore.kernel.org/20260518152559.93038-1-sj@kernel.org
Link: https://lore.kernel.org/20260513011920.119183-1-sj@kernel.org [1]
Fixes: 9277d0367b ("mm/damon/sysfs-schemes: implement scheme region directory")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> # 6.2.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Initialize nr_pages to 1 at the start of each loop iteration, like
folio_referenced_one() does.
Without this, nr_pages computed by a previous folio_unmap_pte_batch() call
can be reused on a later iteration that does not run
folio_unmap_pte_batch() again.
mmap a 64K large folio with MAP_ANONYMOUS | MAP_DROPPABLE, then call
madvise(MADV_FREE), then make the last page device-exclusive via
HMM_DMIRROR_EXCLUSIVE.
Trigger node reclaim through sysfs. Now, in try_to_unmap_one(), we will
first clear the first 15 out of 16 entries mapping the lazyfree folio.
This will set nr_pages to 15. In the next pvmw walk, this nr_pages gets
reused on a device-exclusive pte, thus potentially corrupting folio
refcount/mapcount.
At the moment, I have a userspace program which can make the kernel spit
out a trace, but the blow up is in folio_referenced_one(), because there
are existing bugs in the interaction between device-private and rmap
(which too I am investigating). I did a one liner kernel change to avoid
going into folio_referenced_one(), and the kernel blows up at
folio_remove_rmap_ptes in try_to_unmap_one which is what I wanted.
Note that the bug is there not since file folio batching but lazyfree
folio batching, since device-exclusive only works for anonymous folios.
Userspace visible effect is simply kernel crashing somewhere due to
refcount/mapcount corruption.
Link: https://lore.kernel.org/20260518063656.3721056-1-dev.jain@arm.com
Fixes: 354dffd295 ("mm: support batched unmap for lazyfree large folios during reclamation")
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: Barry Song <baohua@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Harry Yoo <harry@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A crash was observed in zram_writeback_endio due to a NULL pointer
dereference in wake_up. The root cause is a race condition between the
bio completion handler (zram_writeback_endio) and the writeback task.
In zram_writeback_endio, wake_up() is called on &wb_ctl->done_wait after
releasing wb_ctl->done_lock. This creates a race window where the
writeback task can see num_inflight become 0, return, and free wb_ctl
before zram_writeback_endio calls wake_up().
CPU 0 (zram_writeback_endio) CPU 1 (writeback_store)
============================ ============================
zram_writeback_slots
zram_submit_wb_request
zram_submit_wb_request
wait_event(wb_ctl->done_wait)
spin_lock(&wb_ctl->done_lock);
list_add(&req->entry, &wb_ctl->done_reqs);
spin_unlock(&wb_ctl->done_lock);
wake_up(&wb_ctl->done_wait);
zram_complete_done_reqs
spin_lock(&wb_ctl->done_lock);
list_add(&req->entry, &wb_ctl->done_reqs);
spin_unlock(&wb_ctl->done_lock);
while (num_inflight) > 0)
spin_lock(&wb_ctl->done_lock);
list_del(&req->entry);
spin_unlock(&wb_ctl->done_lock);
// num_inflight becomes 0
atomic_dec(num_inflight);
// Leave zram_writeback_slots
// Free wb_ctl
release_wb_ctl(wb_ctl);
// UAF crash!
wake_up(&wb_ctl->done_wait);
This patch fixes this race by using RCU. By protecting wb_ctl with
rcu_read_lock() in zram_writeback_endio and using kfree_rcu() to free it,
we ensure that wb_ctl remains valid during the execution of
zram_writeback_endio.
Link: https://lore.kernel.org/20260512074918.2606208-1-richardycc@google.com
Fixes: f405066a1f ("zram: introduce writeback bio batching")
Signed-off-by: Richard Chang <richardycc@google.com>
Suggested-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Suggested-by: Minchan Kim <minchan@kernel.org>
Acked-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Martin Liu <liumartin@google.com>
Cc: wang wei <a929244872@163.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X. But the
implied seal is set after the check that makes sure the memfd can not have
any writable mappings. This means one can use SEAL_EXEC to apply
SEAL_WRITE while having writeable mappings.
This breaks the contract that SEAL_WRITE provides and can be used by an
attacker to pass a memfd that appears to be write sealed but can still be
modified arbitrarily.
Fix this by adding the implied seals before the call for
mapping_deny_writable() is done.
Link: https://lore.kernel.org/20260505133922.797635-1-pratyush@kernel.org
Fixes: c4f75bc8bd ("mm/memfd: add write seals when apply SEAL_EXEC to executable memfd")
Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: Jeff Xu <jeffxu@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kees Cook <kees@kernel.org>
Cc: "David Hildenbrand (Arm)" <david@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The checkpoint/restore sysctl path can request the next SysV IPC id
through ids->next_id. ipc_idr_alloc() currently forwards that request to
idr_alloc() with an open-ended upper bound.
If the valid tail of the SysV IPC id space is full, the allocation can
spill beyond ipc_mni. The returned SysV IPC id still uses the normal
index encoding, so later lookup and removal can target the wrong slot.
This leaves the real IDR entry behind and breaks the IDR state for the
object.
The bug is in ipc_idr_alloc() in the checkpoint/restore path.
1. ids->next_id is passed to:
idr_alloc(&ids->ipcs_idr, new, ipcid_to_idx(next_id), 0, ...)
2. The zero upper bound makes the allocation effectively open-ended.
Once the valid SysV IPC tail is occupied, idr_alloc() can spill past
ipc_mni and allocate an entry beyond the valid IPC id range.
3. The new object id is still encoded with the narrower SysV IPC index
width:
new->id = (new->seq << ipcmni_seq_shift()) + idx
4. Later removal goes through ipc_rmid(), which uses:
ipcid_to_idx(ipcp->id)
That truncates the real IDR index. An object actually stored at a
high index can then be removed as if it lived at a low in-range
index.
5. For shared memory, shm_destroy() frees the current object anyway, but
the real high IDR slot is left behind as a dangling pointer.
6. A subsequent walk of /proc/sysvipc/shm reaches the stale IDR entry
and dereferences freed memory.
Prevent this by bounding the requested allocation to ipc_mni so the
checkpoint/restore path fails once the valid range is exhausted.
Link: https://lore.kernel.org/cover.1778336914.git.linpu5433@gmail.com
Link: https://lore.kernel.org/2eebe949bfa7d1f6e13b5be6a92c64c850ce9d45.1778336914.git.linpu5433@gmail.com
Fixes: 03f5956680 ("ipc: add sysctl to specify desired next object id")
Signed-off-by: Linpu Yu <linpu5433@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Cc: Kees Cook <kees@kernel.org>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This reverts commit ea52cb24cd ("mm/hugetlbfs: update hugetlbfs to use
mmap_prepare") with conflict resolution to account for changes in commit
ea52cb24cd ("mm/hugetlbfs: update hugetlbfs to use mmap_prepare").
The patch incorrectly handled hugetlb VMA lock allocation at the
mmap_prepare stage, where a failed allocation occurring after mmap_prepare
is called might result in the lock leaking.
There is no risk of a merge causing a similar issues, as
VMA_DONTEXPAND_BIT is set for hugetlb mappings.
As a first step in addressing this issue, simply revert the change so we
can rework how we do this having corrected the underlying issues.
We maintain the VMA flags changes as best we can, accounting for the fact
that we were working with a VMA descriptor previously and propagating
like-for-like changes for this.
Note that we invoke vma_set_flags() and do not call vma_start_write() as
vm_flags_set() does. This is OK as it's being done in an .mmap hook where
the VMA is not yet linked into the tree so nobody else can be accessing
it.
Link: https://lore.kernel.org/20260512160643.266960-1-ljs@kernel.org
Fixes: ea52cb24cd ("mm/hugetlbfs: update hugetlbfs to use mmap_prepare")
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Reported-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Closes: https://lore.kernel.org/linux-mm/20260425070700.562229-1-25181214217@stu.xidian.edu.cn/
Acked-by: Muchun Song <muchun.song@linux.dev>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Update my email address from @ge.com to @gehealthcare.com after GE
HealthCare was spun-off from GE.
Link: https://lore.kernel.org/20260506063335.3-1-ian.ray@gehealthcare.com
Signed-off-by: Ian Ray <ian.ray@gehealthcare.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Cc: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Both GCC [1] and Clang [2] consider the generic version of _THIS_IP_ to
be broken:
#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
In particular, the address of a label is only expected to be used with a
computed goto.
While the generic version more or less works today, it is known to be
brittle and may break with current and future optimizations. For
example, Clang -O2 always returns 1 when this function is inlined:
static inline unsigned long get_ip(void)
{ return ({ __label__ __here; __here: (unsigned long)&&__here; }); }
Fix it by overriding _THIS_IP_ in <asm/linkage.h> (which is included by
<linux/instruction_pointer.h>) using an architecture-specific inline asm
version. Additionally, avoiding taking the address of a label prevents
compilers from emitting spurious indirect branch targets (e.g. ENDBR or
BTI) under control-flow integrity schemes.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120071 [1]
Link: https://github.com/llvm/llvm-project/issues/138272 [2]
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Add Simon Schuster as a co-maintainer for the nios2 architecture and
mark it as supported.
Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Introduce smb_validate_ntsd_sid() helper to safely validate Owner SID
and Group SID inside the NT Security Descriptor (smb_ntsd) retrieved
from the parent directory.
Cc: stable@vger.kernel.org
Signed-off-by: Junyi Liu <moss80199@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
After a durable reconnect succeeds, ksmbd_reopen_durable_fd() republishes
the same ksmbd_file into the session volatile-id table. If smb2_open()
then takes a later error path, cleanup first calls ksmbd_fd_put(work, fp)
and then unconditionally calls ksmbd_put_durable_fd(dh_info.fp).
In this case fp and dh_info.fp are the same object. The first put drops the
reconnect lookup reference, but the final durable put can run
__ksmbd_close_fd(NULL, fp). Because the final close is not session-aware,
it can free the file object without removing the volatile-id entry that was
just published into the session table.
Use the session-aware put for the final reconnect drop when the reconnect
had already succeeded and the error path is cleaning up the republished
file. Earlier reconnect failures, before fp is assigned to dh_info.fp, keep
using the durable-only put path.
Fixes: 1baff47b81 ("ksmbd: fix use-after-free in smb2_open during durable reconnect")
Signed-off-by: Junyi Liu <moss80199@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Current release - fix to a fix:
- Bluetooth: btmtk: accept too short WMT FUNC_CTRL events
- vsock/virtio: relax the recently added memory limit a little
Current release - regressions:
- IB/IPoIB: make sure IB drivers always use async set_rx_mode since
some (mlx5) are now required to use it due to locking changes
Previous releases - regressions:
- udp: fix UDP length on last GSO_PARTIAL segment
- af_unix: fix UAF read of tail->len in unix_stream_data_wait()
- tcp: fix stale per-CPU tcp_tw_isn leak enabling ISN prediction
- mlx5e: fix unlocked writing to ICOSQ, breaking AF_XDP
Previous releases - always broken:
- tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
- ipv4: raw: reject IP_HDRINCL packets with ihl < 5
- Bluetooth: a lot of locking and concurrency fixes (as always)
- batman-adv (mesh wireless networking): a lot of random fixes
for issues reported by security researchers and Sashiko
- netfilter: same thing, a lot of small security-ish fixes
all over the place, nothing really stands out
Misc:
- bring back the old 3c509 driver, Maciej wants to maintain it
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from Bluetooth, wireless and netfilter.
Craziness continues with no end in sight. Even discounting the driver
revert this is a pretty huge PR for standards of the previous era. I'd
speculate - we haven't seen the worst of it, yet. Good news, I guess,
is that so far we haven't seen many (any?) cases of "AI reported a
bug, we fixed it and a real user regressed".
Current release - fix to a fix:
- Bluetooth: btmtk: accept too short WMT FUNC_CTRL events
- vsock/virtio: relax the recently added memory limit a little
Current release - regressions:
- IB/IPoIB: make sure IB drivers always use async set_rx_mode since
some (mlx5) are now required to use it due to locking changes
Previous releases - regressions:
- udp: fix UDP length on last GSO_PARTIAL segment
- af_unix: fix UAF read of tail->len in unix_stream_data_wait()
- tcp: fix stale per-CPU tcp_tw_isn leak enabling ISN prediction
- mlx5e: fix unlocked writing to ICOSQ, breaking AF_XDP
Previous releases - always broken:
- tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
- ipv4: raw: reject IP_HDRINCL packets with ihl < 5
- Bluetooth: a lot of locking and concurrency fixes (as always)
- batman-adv (mesh wireless networking): a lot of random fixes for
issues reported by security researchers and Sashiko
- netfilter: same thing, a lot of small security-ish fixes all over
the place, nothing really stands out
Misc:
- bring back the old 3c509 driver, Maciej wants to maintain it"
* tag 'net-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (187 commits)
net: enetc: avoid VF->PF mailbox timeout during SR-IOV teardown
net: enetc: fix init and teardown order to prevent use of unsafe resources
net: enetc: fix unbounded loop and interrupt handling in VF-to-PF messaging
net: enetc: fix DMA write to freed memory in enetc_msg_free_mbx()
net: enetc: fix race condition in VF MAC address configuration
net: enetc: fix TOCTOU race and validate VF MAC address
net: enetc: add ratelimiting to VF mailbox error messages
net: enetc: fix missing error code when pf->vf_state allocation fails
net: enetc: fix incorrect mailbox message status returned to VFs
net: bridge: prevent too big nested attributes in br_fill_linkxstats()
l2tp: use list_del_rcu in l2tp_session_unhash
net: bcmgenet: keep RBUF EEE/PM disabled
ethernet: 3c509: Fix most coding style issues
ethernet: 3c509: Update documentation to match MAINTAINERS
ethernet: 3c509: Add GPL 2.0 SPDX license identifier
ethernet: 3c509: Fix AUI transceiver type selection
Revert "drivers: net: 3com: 3c509: Remove this driver"
tools: ynl: support listening on all nsids
net: gro: don't merge zcopy skbs
pds_core: ensure null-termination for firmware version strings
...
Flush the current TLB when xAVIC *or* x2AVIC is activated, as KVM is
(apparently) responsible for purging TLB entries when transitioning from
xAVIC to x2AVIC. The APM says a whole lot of nothing about TLB flushing
with respect to (x2)AVIC, but empirical data strongly suggests hardware
also does a whole lot of nothing.
Failure to flush the TLB when enabling x2AVIC can lead to guest accesses
to the APIC base address getting incorrectly redirected to the virtual
APIC page. The flaw most visibly manifests as failures in KVM-Unit-Test's
verify_disabled_apic_mmio() testcase when x2APIC is enabled (though for
reasons unknown, the test only reliably fails with EFI builds).
Fixes: 0ccf3e7cb9 ("KVM: SVM: Flush the "current" TLB when activating AVIC")
Fixes: 4d1d7942e3 ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Cc: stable@vger.kernel.org
Cc: Naveen N Rao (AMD) <naveen@kernel.org>
Link: https://patch.msgid.link/20260515171536.1841645-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use kvm_register_mark_dirty() instead of kvm_register_is_dirty() to
actually mark VCPU_EXREG_ERAPS as dirty when emulating
INVPCID_TYPE_SINGLE_CTXT. kvm_register_is_dirty() is a read-only
predicate whose return value is discarded, making the call a no-op.
Without this fix, a single-context INVPCID will not trigger a RAP clear
on the next VMRUN, breaking the ERAPS security guarantee.
Fixes: db5e824964 ("KVM: SVM: Virtualize and advertise support for ERAPS")
Signed-off-by: Emily Ehlert <ehemily@amazon.de>
Link: https://patch.msgid.link/20260518135956.82569-1-ehemily@amazon.de
Signed-off-by: Sean Christopherson <seanjc@google.com>
setup where many RBD devices are frequently mapped and unmapped, marked
for stable.
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Merge tag 'ceph-for-7.1-rc5' of https://github.com/ceph/ceph-client
Pull ceph fix from Ilya Dryomov:
"A fix for an 'rbd unmap' race condition which popped up on a
production setup where many RBD devices are frequently mapped and
unmapped, marked for stable"
* tag 'ceph-for-7.1-rc5' of https://github.com/ceph/ceph-client:
rbd: eliminate a race in lock_dwork draining on unmap
The F_GETLK fcntl can work with either read access or write access or
both. It can query F_RDLCK and F_WRLCK locks in either case.
However lockd currently treats F_GETLK similar to F_SETLK in that read
access is required to query an F_RDLCK lock and write access is required
to query a F_WRLCK lock.
This is wrong and can cause problems - e.g. when qemu accesses a
read-only (e.g. iso) filesystem image over NFS (though why it queries
if it can get a write lock - I don't know. But it does, and this works
with local filesystems).
So we need TEST requests to be handled differently. To do this:
- change nlm_do_fopen() to accept O_RDWR as a mode and in that case
succeed if either a O_RDONLY or O_WRONLY file can be opened.
- change nlm_lookup_file() to accept a mode argument from caller,
instead of deducing base on lock time, and pass that on to nlm_do_fopen()
- change nlm4svc_retrieve_args() and nlmsvc_retrieve_args() to detect
TEST requests and pass O_RDWR as a mode to nlm_lookup_file, passing
the same mode as before for other requests. Also set
lock->fl.c.flc_file to whichever file is available for TEST requests.
- change nlmsvc_testlock() to also not calculate the mode, but to use
whatever was stored in lock->fl.c.flc_file.
This behaviour of lockd - requesting O_WRONLY access to TEST for
exclusive locks - has been present at least since git history began.
However it was hidden until recently because knfsd ignored the access
requested by lockd and required only READ access for all locking
requests (unless the underlying filesystem provided an f_op->open
function which checked access permissions).
The commit mentioned in Fixes: below changed nfsd_permission() to NOT
override the access request for LOCK requests and this exposed the bug
that we are now fixing.
Note that there is another issue that this patch does not address.
The flock(.., LOCK_EX) call is permitted on a read-only file descriptor.
Linux NFS maps this to NLM locking as whole-file byte-range locks.
nfsd will see this as though it were fcntl( F_SETLK (F_WRLCK)) and will
now require write access, which it might not be able to get.
It is not clear if this is a problem in practice, or what the best
solution might be. So no attempt is made to address it.
Reported-by: Tj <tj.iam.tj@proton.me>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1128861
Fixes: 4cc9b9f2bf ("nfsd: refine and rename NFSD_MAY_LOCK")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The nfsd_ctl_fh_key_set tracepoint was introduced to capture
operator activity on the filehandle signing key. Earlier revisions
logged the key bytes verbatim; the version that landed hashes the
16 key bytes through crc32_le and stores the result.
CRC32 is a linear projection of its input rather than a one-way
function, and truncating any hash of fixed-size secret material
leaves the key recoverable under offline brute force when the
threat model includes an attacker with access to the trace ring.
The operational question the fingerprint was meant to answer is
whether a NFSD_CMD_THREADS_SET call that carries an
NFSD_A_SERVER_FH_KEY attribute actually replaced the active key or
re-installed the value already in place. Answer that question
directly: compare the incoming key bytes against the current
nn->fh_key inside nfsd_nl_fh_key_set() and surface a single bit to
the tracepoint. The event now prints "updated" when the stored
key changed and "unmodified" otherwise. A first set that fails
kmalloc reports "unmodified" because no key was installed.
Reported-by: jaeyeong <fin@spl.team>
Fixes: 62346217fd ("NFSD: Add a key for signing filehandles")
Cc: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit 7b546bd899 ("sunrpc/cache: improve RCU safety in
cache_list walking.") changed the tail of __cache_seq_start()
to unconditionally store
*pos = ((long long)hash << 32) + 1
before returning, dropping a prior "hash >= cd->hash_size"
guard. When the while loop exits because every remaining
bucket was empty, hash equals cd->hash_size, so the stored
*pos is one position past the table's last valid bucket.
seq_read_iter() caches that index in m->index. A subsequent
pread(2) at the same file offset skips traverse() and hands
the stored index back to __cache_seq_start(), which decodes
hash = cd->hash_size and dereferences
cd->hash_table[cd->hash_size] -- one hlist_head past the end
of the kzalloc'd table.
KASAN reports an eight-byte slab-out-of-bounds read at the
tail of the 2048-byte hash_table allocation for the NFSD
export cache (EXPORT_HASHMAX * sizeof(struct hlist_head) ==
256 * 8).
Reject an input hash that is out of range before touching the
hash table. cache_seq_next() already bounds-checks its own
loop; the start routine needs to be symmetric.
Reported-by: syzbot+60cfa08822470bbebe44@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=60cfa08822470bbebe44
Fixes: 7b546bd899 ("sunrpc/cache: improve RCU safety in cache_list walking.")
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
- Fix reporting MISSED EVENTS in trace iterator
When the "trace" file is read with tracing enabled, if the writer
were to pass the iterator reader, it resets, sets a "missed_events"
flag and continues. The tracing output checks for missed events and
if there are some, it prints out "[LOST EVENTS]" to let the user
know events were dropped.
But the clearing of the missed_events happened when the tracing system
queried the ring buffer iterator about missed events. This was premature
as the ring buffer is per CPU, and the tracing code reads all the
CPU buffers and checks for missed events when it is read. If the
CPU iterator that had missed events isn't printed next, the output
for the LOST EVENTS is lost.
Clear the missed_events flag when the iterator moves to the next event
and not when the missed_events flag is queried. Also clear it on reset.
- Flush and stop the persistent ring buffer on panic
On panic the persistent ring buffer is used to debug what caused the
panic. But on some architectures, it requires flushing the memory
from cache, otherwise, the ring buffer persistent memory may not have
the last events and this could also cause the ring buffer to be
corrupted on the next boot.
- Fix nr_subbufs initialization in simple_ring_buffer_init_mm
The remote simple ring buffer meta data nr_subbufs is initialized
too early and gets cleared later on, making it zero and not reflect
the actual number of sub-buffers.
- Fix unload_page for simple_ring_buffer init rollback
On error, the pages loaded need to be unloaded. To unload a page
it is expected that: page = load_page(va); -> unload_page(page).
But the code was doing: unload_page(va) and not unload_page(page).
- Create output file from cmd_check_undefined
The check for undefined symbols checks if the file *.o.checked exists
and if so it skips doing the work. But the *.o.checked file never
was created making every build do the work even when it was already
done previously.
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Merge tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer fixes from Steven Rostedt:
- Fix reporting MISSED EVENTS in trace iterator
When the "trace" file is read with tracing enabled, if the writer
were to pass the iterator reader, it resets, sets a "missed_events"
flag and continues. The tracing output checks for missed events and
if there are some, it prints out "[LOST EVENTS]" to let the user know
events were dropped.
But the clearing of the missed_events happened when the tracing
system queried the ring buffer iterator about missed events. This was
premature as the ring buffer is per CPU, and the tracing code reads
all the CPU buffers and checks for missed events when it is read. If
the CPU iterator that had missed events isn't printed next, the
output for the LOST EVENTS is lost.
Clear the missed_events flag when the iterator moves to the next
event and not when the missed_events flag is queried. Also clear it
on reset.
- Flush and stop the persistent ring buffer on panic
On panic the persistent ring buffer is used to debug what caused the
panic. But on some architectures, it requires flushing the memory
from cache, otherwise, the ring buffer persistent memory may not have
the last events and this could also cause the ring buffer to be
corrupted on the next boot.
- Fix nr_subbufs initialization in simple_ring_buffer_init_mm
The remote simple ring buffer meta data nr_subbufs is initialized too
early and gets cleared later on, making it zero and not reflect the
actual number of sub-buffers.
- Fix unload_page for simple_ring_buffer init rollback
On error, the pages loaded need to be unloaded. To unload a page it
is expected that: page = load_page(va); -> unload_page(page). But the
code was doing: unload_page(va) and not unload_page(page).
- Create output file from cmd_check_undefined
The check for undefined symbols checks if the file *.o.checked exists
and if so it skips doing the work. But the *.o.checked file never was
created making every build do the work even when it was already done
previously.
* tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Create output file from cmd_check_undefined
tracing: Fix unload_page for simple_ring_buffer init rollback
tracing: Fix nr_subbufs initialization in simple_ring_buffer_init_mm()
ring-buffer: Flush and stop persistent ring buffer on panic
ring-buffer: Fix reporting of missed events in iterator
