CVE-2023-54060
Description
In the Linux kernel, the following vulnerability has been resolved:
iommufd: Set end correctly when doing batch carry
Even though the test suite covers this it somehow became obscured that this wasn't working.
The test iommufd_ioas.mock_domain.access_domain_destory would blow up rarely.
end should be set to 1 because this just pushed an item, the carry, to the pfns list.
Sometimes the test would blow up with:
BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 5 PID: 584 Comm: iommufd Not tainted 6.5.0-rc1-dirty #1236 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:batch_unpin+0xa2/0x100 [iommufd] Code: 17 48 81 fe ff ff 07 00 77 70 48 8b 15 b7 be 97 e2 48 85 d2 74 14 48 8b 14 fa 48 85 d2 74 0b 40 0f b6 f6 48 c1 e6 04 48 01 f2 <48> 8b 3a 48 c1 e0 06 89 ca 48 89 de 48 83 e7 f0 48 01 c7 e8 96 dc RSP: 0018:ffffc90001677a58 EFLAGS: 00010246 RAX: 00007f7e2646f000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000fefc4c8d RDI: 0000000000fefc4c RBP: ffffc90001677a80 R08: 0000000000000048 R09: 0000000000000200 R10: 0000000000030b98 R11: ffffffff81f3bb40 R12: 0000000000000001 R13: ffff888101f75800 R14: ffffc90001677ad0 R15: 00000000000001fe FS: 00007f9323679740(0000) GS:ffff8881ba540000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000105ede003 CR4: 00000000003706a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace:
? show_regs+0x5c/0x70 ? __die+0x1f/0x60 ? page_fault_oops+0x15d/0x440 ? lock_release+0xbc/0x240 ? exc_page_fault+0x4a4/0x970 ? asm_exc_page_fault+0x27/0x30 ? batch_unpin+0xa2/0x100 [iommufd] ? batch_unpin+0xba/0x100 [iommufd] __iopt_area_unfill_domain+0x198/0x430 [iommufd] ? __mutex_lock+0x8c/0xb80 ? __mutex_lock+0x6aa/0xb80 ? xa_erase+0x28/0x30 ? iopt_table_remove_domain+0x162/0x320 [iommufd] ? lock_release+0xbc/0x240 iopt_area_unfill_domain+0xd/0x10 [iommufd] iopt_table_remove_domain+0x195/0x320 [iommufd] iommufd_hw_pagetable_destroy+0xb3/0x110 [iommufd] iommufd_object_destroy_user+0x8e/0xf0 [iommufd] iommufd_device_detach+0xc5/0x140 [iommufd] iommufd_selftest_destroy+0x1f/0x70 [iommufd] iommufd_object_destroy_user+0x8e/0xf0 [iommufd] iommufd_destroy+0x3a/0x50 [iommufd] iommufd_fops_ioctl+0xfb/0x170 [iommufd] __x64_sys_ioctl+0x40d/0x9a0 do_syscall_64+0x3c/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
In the Linux kernel iommufd, incorrect 'end' setting in batch carry causes NULL pointer dereference, leading to kernel crash.
The vulnerability is in the Linux kernel's iommufd subsystem, specifically in the batch_unpin function when handling batch carry operations. The root cause is that the variable end is not set correctly (it should be 1 after pushing a carry item to the pfns list), leading to a NULL pointer dereference when batch_unpin attempts to access an invalid memory address [1].
To exploit this flaw, an attacker needs local access to the system and the ability to interact with the iommufd subsystem, such as running the iommufd_ioas.mock_domain.access_domain_destroy test, which may be triggered by unprivileged users depending on configuration. The bug manifests as a kernel NULL pointer dereference, as shown in the stack trace, causing a system crash [1].
The impact is a denial of service (DoS) through a kernel crash. The vulnerability can cause system instability and potential data loss if triggered. No privilege escalation or data tampering is indicated, but a successful exploit can disrupt system availability [1].
Mitigation is straightforward: the fix has been applied in the Linux stable kernel repository (commit 176f36a376c417b58d19f79edfce20db9317eaa2). Systems should update to a kernel version including this commit to prevent the vulnerability. No workarounds are mentioned [1].
AI Insight generated on May 19, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.
Affected products
1Patches
2176f36a376c4b7c822fa6b77Vulnerability mechanics
Generated on May 9, 2026. Inputs: CWE entries + fix-commit diffs from this CVE's patches. Citations validated against bundle.
References
2News mentions
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