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

crypto: ccp - Treat zero-length cert chain as query for blob lengths

When handling a PDH export, treat a zero-length userspace cert chain buffer
as a request to query the length of the relevant blobs. Failure to account
for the zero-length buffer trips a BUG_ON() when running with
CONFIG_DEBUG_VIRTUAL=y due to trying to get the physical address of the
ZERO_SIZE_PTR (returned by kzalloc() on the bogus allocation).

kernel BUG at arch/x86/mm/physaddr.c:28 !
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 30 UID: 0 PID: 28580 Comm: syz.2.18 Kdump: loaded
Tainted: G W 6.18.16-smp-DEV #1 NONE
Tainted: [W]=WARN
Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.62.0-0 11/19/2025
RIP: 0010:__phys_addr+0x16a/0x180 arch/x86/mm/physaddr.c:28
RSP: 0018:ffffc9008329fc80 EFLAGS: 00010293
RAX: ffffffff8179110a RBX: 0000778000000010 RCX: ffff8884e6992600
RDX: 0000000000000000 RSI: 0000000080000010 RDI: 0000778000000010
RBP: ffffc9008329fdf0 R08: 0000000000000dc0 R09: 00000000ffffffff
R10: dffffc0000000000 R11: fffffbfff126d297 R12: dffffc0000000000
R13: 1ffff92010653fc8 R14: 0000000080000010 R15: dffffc0000000000
FS: 0000555556bec9c0(0000) GS:ffff88aa4ce1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd3159e7000 CR3: 00000004fbc44000 CR4: 0000000000350ef0
Call Trace:
<TASK>
[<ffffffff853d3869>] sev_ioctl_do_pdh_export+0x559/0x7a0 drivers/crypto/ccp/sev-dev.c:2308
[<ffffffff853d1fdd>] sev_ioctl+0x2cd/0x480 drivers/crypto/ccp/sev-dev.c:2556
[<ffffffff82549ebc>] vfs_ioctl fs/ioctl.c:52 [inline]
[<ffffffff82549ebc>] __do_sys_ioctl fs/ioctl.c:598 [inline]
[<ffffffff82549ebc>] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
[<ffffffff8630115f>] do_syscall_x64 arch/x86/entry/syscall_64.c:64 [inline]
[<ffffffff8630115f>] do_syscall_64+0x9f/0xf40 arch/x86/entry/syscall_64.c:98
[<ffffffff81000136>] entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fd3158eac39
</TASK>

Thankfully, the bug is benign outside of CONFIG_DEBUG_VIRTUAL=y as getting
the physical address is just arithmetic, and the PSP errors out before
trying to write to the garbage address (which it must, otherwise querying
the blob lengths would clobber memory at pfn=0).
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 28 Aug 2026 07:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Treat zero-length cert chain as query for blob lengths When handling a PDH export, treat a zero-length userspace cert chain buffer as a request to query the length of the relevant blobs. Failure to account for the zero-length buffer trips a BUG_ON() when running with CONFIG_DEBUG_VIRTUAL=y due to trying to get the physical address of the ZERO_SIZE_PTR (returned by kzalloc() on the bogus allocation). kernel BUG at arch/x86/mm/physaddr.c:28 ! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 30 UID: 0 PID: 28580 Comm: syz.2.18 Kdump: loaded Tainted: G W 6.18.16-smp-DEV #1 NONE Tainted: [W]=WARN Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.62.0-0 11/19/2025 RIP: 0010:__phys_addr+0x16a/0x180 arch/x86/mm/physaddr.c:28 RSP: 0018:ffffc9008329fc80 EFLAGS: 00010293 RAX: ffffffff8179110a RBX: 0000778000000010 RCX: ffff8884e6992600 RDX: 0000000000000000 RSI: 0000000080000010 RDI: 0000778000000010 RBP: ffffc9008329fdf0 R08: 0000000000000dc0 R09: 00000000ffffffff R10: dffffc0000000000 R11: fffffbfff126d297 R12: dffffc0000000000 R13: 1ffff92010653fc8 R14: 0000000080000010 R15: dffffc0000000000 FS: 0000555556bec9c0(0000) GS:ffff88aa4ce1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd3159e7000 CR3: 00000004fbc44000 CR4: 0000000000350ef0 Call Trace: <TASK> [<ffffffff853d3869>] sev_ioctl_do_pdh_export+0x559/0x7a0 drivers/crypto/ccp/sev-dev.c:2308 [<ffffffff853d1fdd>] sev_ioctl+0x2cd/0x480 drivers/crypto/ccp/sev-dev.c:2556 [<ffffffff82549ebc>] vfs_ioctl fs/ioctl.c:52 [inline] [<ffffffff82549ebc>] __do_sys_ioctl fs/ioctl.c:598 [inline] [<ffffffff82549ebc>] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584 [<ffffffff8630115f>] do_syscall_x64 arch/x86/entry/syscall_64.c:64 [inline] [<ffffffff8630115f>] do_syscall_64+0x9f/0xf40 arch/x86/entry/syscall_64.c:98 [<ffffffff81000136>] entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fd3158eac39 </TASK> Thankfully, the bug is benign outside of CONFIG_DEBUG_VIRTUAL=y as getting the physical address is just arithmetic, and the PSP errors out before trying to write to the garbage address (which it must, otherwise querying the blob lengths would clobber memory at pfn=0).
Title crypto: ccp - Treat zero-length cert chain as query for blob lengths
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-28T06:49:00.093Z

Reserved: 2026-08-26T14:34:25.779Z

Link: CVE-2026-80652

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-28T08:16:50.200

Modified: 2026-08-28T08:16:50.200

Link: CVE-2026-80652

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.