CVE-2026-43449 — linux / linux_kernel
Out-of-bounds ReadIn the Linux kernel, the following vulnerability has been resolved:
nvme-pci: Fix slab-out-of-bounds in nvme_dbbuf_set
dev->online_queues is a count incremented in nvme_init_queue. Thus, valid indices are 0 through dev->online_queues − 1.
This patch fixes the loop condition to ensure the index stays within the valid range. Index 0 is excluded because it is the admin queue.
KASAN splat:
================================================================== BUG: KASAN: slab-out-of-bounds in nvme_dbbuf_free drivers/nvme/host/pci.c:377 [inline] BUG: KASAN: slab-out-of-bounds in nvme_dbbuf_set+0x39c/0x400 drivers/nvme/host/pci.c:404 Read of size 2 at addr ffff88800592a574 by task kworker/u8:5/74
CPU: 0 UID: 0 PID: 74 Comm: kworker/u8:5 Not tainted 6.19.0-dirty #10 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Workqueue: nvme-reset-wq nvme_reset_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xea/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xce/0x5d0 mm/kasan/report.c:482 kasan_report+0xdc/0x110 mm/kasan/report.c:595 __asan_report_load2_noabort+0x18/0x20 mm/kasan/report_generic.c:379 nvme_dbbuf_free drivers/nvme/host/pci.c:377 [inline] nvme_dbbuf_set+0x39c/0x400 drivers/nvme/host/pci.c:404 nvme_reset_work+0x36b/0x8c0 drivers/nvme/host/pci.c:3252 process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x65c/0xe60 kernel/workqueue.c:3421 kthread+0x41a/0x930 kernel/kthread.c:463 ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 </TASK>
Allocated by task 34 on cpu 1 at 4.241550s: kasan_save_stack+0x2c/0x60 mm/kasan/common.c:57 kasan_save_track+0x1c/0x70 mm/kasan/common.c:78 kasan_save_alloc_info+0x3c/0x50 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xb5/0xc0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_node_noprof+0x2bf/0x8d0 mm/slub.c:5663 kmalloc_array_node_noprof include/linux/slab.h:1075 [inline] nvme_pci_alloc_dev drivers/nvme/host/pci.c:3479 [inline] nvme_probe+0x2f1/0x1820 drivers/nvme/host/pci.c:3534 local_pci_probe+0xef/0x1c0 drivers/pci/pci-driver.c:324 pci_call_probe drivers/pci/pci-driver.c:392 [inline] __pci_device_probe drivers/pci/pci-driver.c:417 [inline] pci_device_probe+0x743/0x920 drivers/pci/pci-driver.c:451 call_driver_probe drivers/base/dd.c:583 [inline] really_probe+0x29b/0xb70 drivers/base/dd.c:661 __driver_probe_device+0x3b0/0x4a0 drivers/base/dd.c:803 driver_probe_device+0x56/0x1f0 drivers/base/dd.c:833 __driver_attach_async_helper+0x155/0x340 drivers/base/dd.c:1159 async_run_entry_fn+0xa6/0x4b0 kernel/async.c:129 process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x65c/0xe60 kernel/workqueue.c:3421 kthread+0x41a/0x930 kernel/kthread.c:463 ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
The buggy address belongs to the object at ffff88800592a000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 244 bytes to the right of allocated 1152-byte region [ffff88800592a000, ffff88800592a480)
The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5928 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfffffc0000040(head|node=0|zone=1|lastcpupid=0x1fffff) page_type: f5(slab) raw: 000fffffc0000040 ffff888001042000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 000fffffc0000040 ffff888001042000 00000 ---truncated---
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 4.14.210 | 4.15 |
| linux / linux_kernel | 4.19.161 | 4.20 |
| linux / linux_kernel | 5.4.81 | 5.5 |
| linux / linux_kernel | 5.9.12 | 5.10 |
| linux / linux_kernel | 5.10.1 | 5.10.253 |
| linux / linux_kernel | 5.11 | 5.15.203 |
| linux / linux_kernel | 5.16 | 6.1.167 |
| linux / linux_kernel | 6.2 | 6.6.130 |
| linux / linux_kernel | 6.7 | 6.12.78 |
| linux / linux_kernel | 6.13 | 6.18.19 |
| linux / linux_kernel | 6.19 | 6.19.9 |
| linux / linux_kernel | 5.10 | 5.10.x |
| linux / linux_kernel | 5.10-rc5 | 5.10-rc5.x |
| linux / linux_kernel | 5.10-rc6 | 5.10-rc6.x |
| linux / linux_kernel | 5.10-rc7 | 5.10-rc7.x |
| linux / linux_kernel | 7.0-rc1 | 7.0-rc1.x |
| linux / linux_kernel | 7.0-rc2 | 7.0-rc2.x |
| linux / linux_kernel | 7.0-rc3 | 7.0-rc3.x |
- https://git.kernel.org/stable/c/2b9d605c3f0d3262142f196249cd3bd58c857c71
- https://git.kernel.org/stable/c/328c551f0cc81ee776b186b86cc6e5253bb6fda7
- https://git.kernel.org/stable/c/50bad78f03a02d3c0f228edf9912b494d3e7acb9
- https://git.kernel.org/stable/c/78279d2d74c58a0ed64e43cf601a02649771182e
- https://git.kernel.org/stable/c/83e6edd6358326c9c2de31a54bb4a1ec50703f1f
- https://git.kernel.org/stable/c/86183d550559e45e07059bbdf17331fea469e38c
- https://git.kernel.org/stable/c/b4e78f1427c7d6859229ae9616df54e1fc05a516
- https://git.kernel.org/stable/c/d7990c936e25f484b61a5adeeadc1d290a9fd16e
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