{"id":"CVE-2025-39740","state":"PUBLISHED","title":"drm/xe/migrate: prevent potential UAF","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/migrate: prevent potential UAF\n\nIf we hit the error path, the previous fence (if there is one) has\nalready been put() prior to this, so doing a fence_wait could lead to\nUAF. Tweak the flow to do to the put() until after we do the wait.\n\n(cherry picked from commit 9b7ca35ed28fe5fad86e9d9c24ebd1271e4c9c3e)","publishedAt":"2025-09-11T16:52:14.638Z","updatedAt":"2026-08-05T12:04:57.846Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"270172f64b114451876c1b68912653e72ab99f38","status":"affected","lessThan":"7e46fa64a4b94208563c3a5bf1d7f4346f94abea","versionType":"git"},{"version":"270172f64b114451876c1b68912653e72ab99f38","status":"affected","lessThan":"145832fbdd17b1d77ffd6cdd1642259e101d1b7e","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/xe/xe_migrate.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.16.2","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/xe/xe_migrate.c"]}],"references":["https://git.kernel.org/stable/c/7e46fa64a4b94208563c3a5bf1d7f4346f94abea","https://git.kernel.org/stable/c/145832fbdd17b1d77ffd6cdd1642259e101d1b7e"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/39xxx/CVE-2025-39740.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-39740","state":"PUBLISHED","datePublished":"2025-09-11T16:52:14.638Z","dateUpdated":"2026-08-05T12:04:57.846Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T07:20:57.120Z"},"containers":{"cna":{"title":"drm/xe/migrate: prevent potential UAF","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/migrate: prevent potential UAF\n\nIf we hit the error path, the previous fence (if there is one) has\nalready been put() prior to this, so doing a fence_wait could lead to\nUAF. Tweak the flow to do to the put() until after we do the wait.\n\n(cherry picked from commit 9b7ca35ed28fe5fad86e9d9c24ebd1271e4c9c3e)"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"270172f64b114451876c1b68912653e72ab99f38","status":"affected","lessThan":"7e46fa64a4b94208563c3a5bf1d7f4346f94abea","versionType":"git"},{"version":"270172f64b114451876c1b68912653e72ab99f38","status":"affected","lessThan":"145832fbdd17b1d77ffd6cdd1642259e101d1b7e","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/xe/xe_migrate.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.16.2","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/xe/xe_migrate.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7e46fa64a4b94208563c3a5bf1d7f4346f94abea"},{"url":"https://git.kernel.org/stable/c/145832fbdd17b1d77ffd6cdd1642259e101d1b7e"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable loop is reached only through a local userspace mapping of an Intel Xe VRAM buffer object accessed via ptrace//proc/pid/mem/process_vm_readv, or via the local devcoredump snapshot path after a GPU hang. There is no network or adjacent-network exposure.\nAC:L - The attacker deterministically forces multiple loop iterations by choosing the access offset/length against a fragmented VRAM BO (or a large VM snapshot), and forces the error path by saturating the fixed-size kernel_bb_pool and signalling the waiting thread, since drm_suballoc_insert waits interruptibly and returns -ERESTARTSYS. Concurrent migrate traffic that replaces m->fence and drops the last reference is likewise generated by the attacker's own GPU submissions.\nPR:L - Only an unprivileged local user with DRM render-node access (render group, logged-in desktop user, or Android graphics group) is needed to create and mmap a VRAM BO and ptrace its own process. No root, capability, or namespace escalation is required.\nUI:N - The attacker performs the BO creation, mapping, GPU load generation, and the triggering remote-memory access entirely within its own processes. No action by any other user is required.\nS:U - The freed dma_fence and any resulting corruption stay within the host kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - dma_fence_wait() on the freed fence dereferences fence->ops, fence->lock and fence->seqno from reclaimed slab memory, and the attacker can refill that slot with objects of its choosing by submitting more scheduler jobs, yielding an arbitrary kernel-memory read primitive.\nI:H - The same wait path writes into the freed object (list_add on cb_list, setting the ENABLE_SIGNAL flag) and performs an indirect call through fence->ops, so a heap-sprayed replacement gives both a write primitive and control-flow hijack leading to privilege escalation.\nA:H - Even without successful exploitation the use-after-free reliably produces a KASAN splat/oops, and waiting on a fence that will never signal hangs the calling task while holding the BO reservation, denying service."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:04:57.846Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.16.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.17"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}