CVE-2024-49942

Description

From CVE.org

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Prevent null pointer access in xe_migrate_copy xe_migrate_copy designed to copy content of TTM resources. When source resource is null, it will trigger a NULL pointer dereference in xe_migrate_copy. To avoid this situation, update lacks source flag to true for this case, the flag will trigger xe_migrate_clear rather than xe_migrate_copy. Issue trace: <7> [317.089847] xe 0000:00:02.0: [drm:xe_migrate_copy [xe]] Pass 14, sizes: 4194304 & 4194304 <7> [317.089945] xe 0000:00:02.0: [drm:xe_migrate_copy [xe]] Pass 15, sizes: 4194304 & 4194304 <1> [317.128055] BUG: kernel NULL pointer dereference, address: 0000000000000010 <1> [317.128064] #PF: supervisor read access in kernel mode <1> [317.128066] #PF: error_code(0x0000) - not-present page <6> [317.128069] PGD 0 P4D 0 <4> [317.128071] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI <4> [317.128074] CPU: 1 UID: 0 PID: 1440 Comm: kunit_try_catch Tainted: G U N 6.11.0-rc7-xe #1 <4> [317.128078] Tainted: [U]=USER, [N]=TEST <4> [317.128080] Hardware name: Intel Corporation Lunar Lake Client Platform/LNL-M LP5 RVP1, BIOS LNLMFWI1.R00.3221.D80.2407291239 07/29/2024 <4> [317.128082] RIP: 0010:xe_migrate_copy+0x66/0x13e0 [xe] <4> [317.128158] Code: 00 00 48 89 8d e0 fe ff ff 48 8b 40 10 4c 89 85 c8 fe ff ff 44 88 8d bd fe ff ff 65 48 8b 3c 25 28 00 00 00 48 89 7d d0 31 ff <8b> 79 10 48 89 85 a0 fe ff ff 48 8b 00 48 89 b5 d8 fe ff ff 83 ff <4> [317.128162] RSP: 0018:ffffc9000167f9f0 EFLAGS: 00010246 <4> [317.128164] RAX: ffff8881120d8028 RBX: ffff88814d070428 RCX: 0000000000000000 <4> [317.128166] RDX: ffff88813cb99c00 RSI: 0000000004000000 RDI: 0000000000000000 <4> [317.128168] RBP: ffffc9000167fbb8 R08: ffff88814e7b1f08 R09: 0000000000000001 <4> [317.128170] R10: 0000000000000001 R11: 0000000000000001 R12: ffff88814e7b1f08 <4> [317.128172] R13: ffff88814e7b1f08 R14: ffff88813cb99c00 R15: 0000000000000001 <4> [317.128174] FS: 0000000000000000(0000) GS:ffff88846f280000(0000) knlGS:0000000000000000 <4> [317.128176] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [317.128178] CR2: 0000000000000010 CR3: 000000011f676004 CR4: 0000000000770ef0 <4> [317.128180] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 <4> [317.128182] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400 <4> [317.128184] PKRU: 55555554 <4> [317.128185] Call Trace: <4> [317.128187] <TASK> <4> [317.128189] ? show_regs+0x67/0x70 <4> [317.128194] ? __die_body+0x20/0x70 <4> [317.128196] ? __die+0x2b/0x40 <4> [317.128198] ? page_fault_oops+0x15f/0x4e0 <4> [317.128203] ? do_user_addr_fault+0x3fb/0x970 <4> [317.128205] ? lock_acquire+0xc7/0x2e0 <4> [317.128209] ? exc_page_fault+0x87/0x2b0 <4> [317.128212] ? asm_exc_page_fault+0x27/0x30 <4> [317.128216] ? xe_migrate_copy+0x66/0x13e0 [xe] <4> [317.128263] ? __lock_acquire+0xb9d/0x26f0 <4> [317.128265] ? __lock_acquire+0xb9d/0x26f0 <4> [317.128267] ? sg_free_append_table+0x20/0x80 <4> [317.128271] ? lock_acquire+0xc7/0x2e0 <4> [317.128273] ? mark_held_locks+0x4d/0x80 <4> [317.128275] ? trace_hardirqs_on+0x1e/0xd0 <4> [317.128278] ? _raw_spin_unlock_irqrestore+0x31/0x60 <4> [317.128281] ? __pm_runtime_resume+0x60/0xa0 <4> [317.128284] xe_bo_move+0x682/0xc50 [xe] <4> [317.128315] ? lock_is_held_type+0xaa/0x120 <4> [317.128318] ttm_bo_handle_move_mem+0xe5/0x1a0 [ttm] <4> [317.128324] ttm_bo_validate+0xd1/0x1a0 [ttm] <4> [317.128328] shrink_test_run_device+0x721/0xc10 [xe] <4> [317.128360] ? find_held_lock+0x31/0x90 <4> [317.128363] ? lock_release+0xd1/0x2a0 <4> [317.128365] ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [kunit] <4> [317.128370] xe_bo_shrink_kunit+0x11/0x20 [xe] <4> [317.128397] kunit_try_run_case+0x6e/0x150 [kunit] <4> [317.128400] ? trace_hardirqs_on+0x1e/0xd0 <4> [317.128402] ? _raw_spin_unlock_irqrestore+0x31/0x60 <4> [317.128404] kunit_generic_run_threadfn_adapter+0x1e/0x40 [ku ---truncated---

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.55.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactHighHighN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart

NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.

Integrity,Confidentiality

Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory

In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Frequently Asked Questions

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