{ "schema_version": "1.6.1", "id": "RPI-CVE-2025-71162", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2025-71162" ], "published": "2026-01-25T14:36:48Z", "summary": "dmaengine: tegra-adma: Fix use-after-free", "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndmaengine: tegra-adma: Fix use-after-free\n\nA use-after-free bug exists in the Tegra ADMA driver when audio streams\nare terminated, particularly during XRUN conditions. The issue occurs\nwhen the DMA buffer is freed by tegra_adma_terminate_all() before the\nvchan completion tasklet finishes accessing it.\n\nThe race condition follows this sequence:\n\n 1. DMA transfer completes, triggering an interrupt that schedules the\n completion tasklet (tasklet has not executed yet)\n 2. Audio playback stops, calling tegra_adma_terminate_all() which\n frees the DMA buffer memory via kfree()\n 3. The scheduled tasklet finally executes, calling vchan_complete()\n which attempts to access the already-freed memory\n\nSince tasklets can execute at any time after being scheduled, there is\nno guarantee that the buffer will remain valid when vchan_complete()\nruns.\n\nFix this by properly synchronizing the virtual channel completion:\n - Calling vchan_terminate_vdesc() in tegra_adma_stop() to mark the\n descriptors as terminated instead of freeing the descriptor.\n - Add the callback tegra_adma_synchronize() that calls\n vchan_synchronize() which kills any pending tasklets and frees any\n terminated descriptors.\n\nCrash logs:\n[ 337.427523] BUG: KASAN: use-after-free in vchan_complete+0x124/0x3b0\n[ 337.427544] Read of size 8 at addr ffff000132055428 by task swapper/0/0\n\n[ 337.427562] Call trace:\n[ 337.427564] dump_backtrace+0x0/0x320\n[ 337.427571] show_stack+0x20/0x30\n[ 337.427575] dump_stack_lvl+0x68/0x84\n[ 337.427584] print_address_description.constprop.0+0x74/0x2b8\n[ 337.427590] kasan_report+0x1f4/0x210\n[ 337.427598] __asan_load8+0xa0/0xd0\n[ 337.427603] vchan_complete+0x124/0x3b0\n[ 337.427609] tasklet_action_common.constprop.0+0x190/0x1d0\n[ 337.427617] tasklet_action+0x30/0x40\n[ 337.427623] __do_softirq+0x1a0/0x5c4\n[ 337.427628] irq_exit+0x110/0x140\n[ 337.427633] handle_domain_irq+0xa4/0xe0\n[ 337.427640] gic_handle_irq+0x64/0x160\n[ 337.427644] call_on_irq_stack+0x20/0x4c\n[ 337.427649] do_interrupt_handler+0x7c/0x90\n[ 337.427654] el1_interrupt+0x30/0x80\n[ 337.427659] el1h_64_irq_handler+0x18/0x30\n[ 337.427663] el1h_64_irq+0x7c/0x80\n[ 337.427667] cpuidle_enter_state+0xe4/0x540\n[ 337.427674] cpuidle_enter+0x54/0x80\n[ 337.427679] do_idle+0x2e0/0x380\n[ 337.427685] cpu_startup_entry+0x2c/0x70\n[ 337.427690] rest_init+0x114/0x130\n[ 337.427695] arch_call_rest_init+0x18/0x24\n[ 337.427702] start_kernel+0x380/0x3b4\n[ 337.427706] __primary_switched+0xc0/0xc8", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:12", "name": "linux" }, "versions": [ "1:6.1.47-1+rpt4" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.1.0-rpi3-rpi-2712", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v6", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v7", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v8", "binary_version": "1:6.1.47-1+rpt4" } ] }, "database_specific": { "per_version": { "1:6.1.47-1+rpt4": { "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e", "upstream_version": "6.1.47", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.162", "compiled_filter": false } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2025-71162" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/5f8d1d66a952d0396671e1f21ff8127a4d14fb4e" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/76992310f80776b4d1f7f8915f59b92883a3e44c" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/ae3eed72de682ddbba507ed2d6b848c21a6b721e" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/59cb421b0902fbef2b9512ae8ba198a20f26b41f" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/cb2c9c4bb1322cc3c9984ad17db8cdd2663879ca" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/be655c3736b3546f39bc8116ffbf2a3b6cac96c4" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/2efd07a7c36949e6fa36a69183df24d368bf9e96" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-05T12:19:11Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 7.8, "cvss_v3_severity": "High", "scenario": "AV:L - The vulnerable path is reached locally through ALSA PCM device ioctls that flow through ASoC and DMAengine into the Tegra ADMA driver; it is not packet-facing.\nAC:L - The attacker controls stream setup, period sizing, and repeated start/termination while causing the hardware period interrupts. A public looped reproducer reliably drives the race window.\nPR:L - No capability or namespace privilege check exists; the process needs only ordinary permission to open the ALSA PCM device, commonly granted to an unprivileged audio-session user.\nUI:N - The attacker can configure, start, and terminate their own PCM stream or induce its XRUN without any separate victim action.\nS:U - The corruption and its effects remain within the host kernel security authority; this is not a guest-host, IOMMU, or other security-boundary bypass.\nC:H - The freed kmalloc-256 descriptor is subsequently dereferenced for callback fields; reclaiming it can enable attacker-influenced kernel execution and arbitrary kernel-memory disclosure.\nI:H - vchan_complete() reads function pointers and a callback parameter from the freed descriptor and invokes a callback, supporting control-flow hijacking and arbitrary kernel modification.\nA:H - The KASAN-confirmed use-after-free can cause a kernel oops or panic, and the attacker can repeat the stream termination or XRUN sequence." } } }