In the Linux kernel, the following vulnerability has been resolved:
Input: zero ff_effect before compat copy in input_ff_effect_from_user
In the compat path input_ff_effect_from_user() aliases the caller's
native struct ff_effect with the smaller struct ff_effect_compat and
copies only the compat sized prefix:
compat_effect = (struct ff_effect_compat *)effect;
if (copy_from_user(compat_effect, buffer,
sizeof(struct ff_effect_compat)))
The tail of the native structure is never written. Callers pass an
uninitialized on-stack object, for example evdev_do_ioctl() for
EVIOCSFF, so those bytes keep their previous stack contents.
input_ff_upload() then stores the full native structure in
ff->effects[id], from where a uinput based force feedback daemon can
read it back via UI_BEGIN_FF_UPLOAD, disclosing kernel stack memory to
userspace.
Zero the effect before the compat copy.
Input: zero ff_effect before compat copy in input_ff_effect_from_user
In the compat path input_ff_effect_from_user() aliases the caller's
native struct ff_effect with the smaller struct ff_effect_compat and
copies only the compat sized prefix:
compat_effect = (struct ff_effect_compat *)effect;
if (copy_from_user(compat_effect, buffer,
sizeof(struct ff_effect_compat)))
The tail of the native structure is never written. Callers pass an
uninitialized on-stack object, for example evdev_do_ioctl() for
EVIOCSFF, so those bytes keep their previous stack contents.
input_ff_upload() then stores the full native structure in
ff->effects[id], from where a uinput based force feedback daemon can
read it back via UI_BEGIN_FF_UPLOAD, disclosing kernel stack memory to
userspace.
Zero the effect before the compat copy.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 06 Oct 2026 09:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: Input: zero ff_effect before compat copy in input_ff_effect_from_user In the compat path input_ff_effect_from_user() aliases the caller's native struct ff_effect with the smaller struct ff_effect_compat and copies only the compat sized prefix: compat_effect = (struct ff_effect_compat *)effect; if (copy_from_user(compat_effect, buffer, sizeof(struct ff_effect_compat))) The tail of the native structure is never written. Callers pass an uninitialized on-stack object, for example evdev_do_ioctl() for EVIOCSFF, so those bytes keep their previous stack contents. input_ff_upload() then stores the full native structure in ff->effects[id], from where a uinput based force feedback daemon can read it back via UI_BEGIN_FF_UPLOAD, disclosing kernel stack memory to userspace. Zero the effect before the compat copy. | |
| Title | Input: zero ff_effect before compat copy in input_ff_effect_from_user | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-06T08:44:38.952Z
Reserved: 2026-09-25T10:25:14.324Z
Link: CVE-2026-98201
No data.
Status : Received
Published: 2026-10-06T09:18:05.900
Modified: 2026-10-06T09:18:05.900
Link: CVE-2026-98201
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.