CVE-2026-98515
Received Received - Intake

Double-Free in Nouveau Linux Kernel Driver

Publication date: 2026-10-18

Last updated on: 2026-10-18

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix double-free in nvif_vmm_dtor On failure, nouveau_cli_init() calls nouveau_cli_fini() to tear the client down. Then, nouveau_drm_open() also enters into its cleanup path and calls nouveau_cli_fini() AGAIN. nouveau_cli_fini() calls nouveau_vmm_fini(): void nouveau_vmm_fini(struct nouveau_vmm *vmm) { nouveau_svmm_fini(&vmm->svmm); nvif_vmm_dtor(&vmm->vmm); vmm->cli = NULL; } Inside nvif_vmm_dtor(), vmm->page is freed unconditionally: void nvif_vmm_dtor(struct nvif_vmm *vmm) { kfree(vmm->page); nvif_object_dtor(&vmm->object); } vmm->page is never cleared after being freed, so the second call of nvif_vmm_dtor() will cause a double-free. Found by fuzzing the nouveau driver with a modified Syzkaller: BUG: KASAN: double-free in nvif_vmm_dtor+0x31/0x50 drivers/gpu/drm/nouveau/nvif/vmm.c:194 Free of addr ffff888010fcdc30 by task syz.0.173/2567 CPU: 1 UID: 0 PID: 2567 Comm: syz.0.173 Not tainted 7.2.0 #24 PREEMPT(lazy) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x95/0xe0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcb/0x5a0 mm/kasan/report.c:482 kasan_report_invalid_free+0xaa/0xd0 mm/kasan/report.c:557 check_slab_allocation+0xe4/0x110 mm/kasan/common.c:235 kasan_slab_pre_free include/linux/kasan.h:199 [inline] slab_free_hook mm/slub.c:2622 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x192/0x590 mm/slub.c:6692 nvif_vmm_dtor+0x31/0x50 drivers/gpu/drm/nouveau/nvif/vmm.c:194 nouveau_vmm_fini+0x16/0x50 drivers/gpu/drm/nouveau/nouveau_vmm.c:127 nouveau_cli_fini+0x10e/0x210 drivers/gpu/drm/nouveau/nouveau_drm.c:225 nouveau_drm_open+0x24e/0x740 drivers/gpu/drm/nouveau/nouveau_drm.c:1255 drm_file_alloc+0x5f2/0xad0 drivers/gpu/drm/drm_file.c:176 drm_open_helper+0x1d7/0x4a0 drivers/gpu/drm/drm_file.c:335 drm_open+0x190/0x3d0 drivers/gpu/drm/drm_file.c:388 drm_stub_open+0x1f2/0x460 drivers/gpu/drm/drm_drv.c:1211 chrdev_open+0x21c/0x660 fs/char_dev.c:411 do_dentry_open+0x59d/0x12b0 fs/open.c:947 vfs_open+0x82/0x390 fs/open.c:1052 do_open fs/namei.c:4700 [inline] path_openat+0x2345/0x3420 fs/namei.c:4863 do_file_open+0x207/0x460 fs/namei.c:4892 do_sys_openat2+0xd1/0x1d0 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x144/0x200 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x690 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc6d687594d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc6d5295008 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fc6d6b06180 RCX: 00007fc6d687594d RDX: 0000000000022501 RSI: 0000200000000000 RDI: ffffffffffffff9c RBP: 00007fc6d691c303 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc6d6b06218 R14: 00007fc6d6b06180 R15: 00007ffd9451d760 </TASK> Allocated by task 2567 on cpu 1 at 163.593900s: kasan_save_stack+0x24/0x50 mm/kasan/common.c:57 kasan_save_track+0x17/0x60 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5334 [inline] __kmalloc_noprof+0x304/0x7c0 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] nvif_vmm_ctor+0x3c0/0x7e0 drivers/gpu/drm/nouveau/nvif/vmm.c:237 nouveau_vmm_init+0x40/0x90 drivers/gpu/drm/nouveau/nouveau_vmm.c:134 nouveau_cli_init+0x7b9/0 ---truncated---

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Meta Information

Published
2026-10-18
Last Modified
2026-10-18
Generated
2026-10-18
AI Q&A
2026-10-18
EPSS Evaluated
N/A
NVD
CVE-2026-98515
EUVD
EUVD-2026-103755

Affected Vendors & Products

Showing 9 associated CPEs
Vendor Product Version / Range
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 20d8a88e557aae5264e793f4626c45cd644c7144
Linux Linux 4.11

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CWE ID Description
CWE-UNKNOWN

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Executive Summary

This is a double-free vulnerability in the Linux kernel's Nouveau graphics driver. It occurs when the nouveau_cli_init() function fails and calls nouveau_cli_fini() to clean up. Later, nouveau_drm_open() also attempts cleanup by calling nouveau_cli_fini() again. The second call triggers nvif_vmm_dtor() which frees memory that was already freed, causing a system crash or potential privilege escalation.

Impact Analysis

This vulnerability could cause system instability, crashes, or arbitrary code execution. An attacker could exploit it to gain elevated privileges on affected systems running the Nouveau driver. Systems using this driver for NVIDIA GPUs are potentially vulnerable.

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