In the Linux kernel, the following vulnerability has been resolved:

pseries/papr-hvpipe: Fix null ptr deref in papr_hvpipe_dev_create_handle()

commit 6d3789d347a7 ("papr-hvpipe: convert papr_hvpipe_dev_create_handle() to FD_PREPARE()"),
changed the create handle to FD_PREPARE(), but it caused kernel
null-ptr-deref because after call to retain_and_null_ptr(src_info),
src_info is re-used for adding it to the global list.

Getting the following kernel panic in papr_hvpipe_dev_create_handle()
when trying to add src_info to the list.
Kernel attempted to write user page (0) - exploit attempt? (uid: 0)
BUG: Kernel NULL pointer dereference on write at 0x00000000
Faulting instruction address: 0xc0000000001b44a0
Oops: Kernel access of bad area, sig: 11 [#1]
...
Call Trace:
papr_hvpipe_dev_ioctl+0x1f4/0x48c (unreliable)
sys_ioctl+0x528/0x1064
system_call_exception+0x128/0x360
system_call_vectored_common+0x15c/0x2ec

Now, the error handling with FD_PREPARE's file cleanup and __free(kfree) auto
cleanup is getting too convoluted. This is mainly because we need to
ensure only 1 user get the srcID handle. To simplify this, we allocate
prepare the src_info in the beginning and add it to the global list
under a spinlock after checking that no duplicates exist.

This simplify the error handling where if the FD_ADD fails, we can
simply remove the src_info from the list and consume any pending msg in
hvpipe to be cleared, after src_info became visible in the global list.

Project Subscriptions

Vendors Products
Linux Kernel Subscribe
Advisories
Source ID Title
Ubuntu USN Ubuntu USN USN-8566-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8568-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8569-1 Linux kernel (HWE) vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 29 May 2026 00:15:00 +0000


Thu, 28 May 2026 14:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-476

Thu, 28 May 2026 10:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: pseries/papr-hvpipe: Fix null ptr deref in papr_hvpipe_dev_create_handle() commit 6d3789d347a7 ("papr-hvpipe: convert papr_hvpipe_dev_create_handle() to FD_PREPARE()"), changed the create handle to FD_PREPARE(), but it caused kernel null-ptr-deref because after call to retain_and_null_ptr(src_info), src_info is re-used for adding it to the global list. Getting the following kernel panic in papr_hvpipe_dev_create_handle() when trying to add src_info to the list. Kernel attempted to write user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on write at 0x00000000 Faulting instruction address: 0xc0000000001b44a0 Oops: Kernel access of bad area, sig: 11 [#1] ... Call Trace: papr_hvpipe_dev_ioctl+0x1f4/0x48c (unreliable) sys_ioctl+0x528/0x1064 system_call_exception+0x128/0x360 system_call_vectored_common+0x15c/0x2ec Now, the error handling with FD_PREPARE's file cleanup and __free(kfree) auto cleanup is getting too convoluted. This is mainly because we need to ensure only 1 user get the srcID handle. To simplify this, we allocate prepare the src_info in the beginning and add it to the global list under a spinlock after checking that no duplicates exist. This simplify the error handling where if the FD_ADD fails, we can simply remove the src_info from the list and consume any pending msg in hvpipe to be cleared, after src_info became visible in the global list.
Title pseries/papr-hvpipe: Fix null ptr deref in papr_hvpipe_dev_create_handle()
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-06-14T17:55:45.082Z

Reserved: 2026-05-13T15:03:33.098Z

Link: CVE-2026-46118

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-05-28T10:16:27.293

Modified: 2026-06-17T10:53:05.860

Link: CVE-2026-46118

cve-icon Redhat

Severity :

Publid Date: 2026-05-28T00:00:00Z

Links: CVE-2026-46118 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-05-28T14:00:18Z

Weaknesses