{"cve":"CVE-2021-46927","nvd":{"published":"2024-02-27T10:15:07.410","modified":"2026-06-17T04:15:52.670","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnitro_enclaves: Use get_user_pages_unlocked() call to handle mmap assert\n\nAfter commit 5b78ed24e8ec (\"mm/pagemap: add mmap_assert_locked()\nannotations to find_vma*()\"), the call to get_user_pages() will trigger\nthe mmap assert.\n\nstatic inline void mmap_assert_locked(struct mm_struct *mm)\n{\n\tlockdep_assert_held(&mm->mmap_lock);\n\tVM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);\n}\n\n[   62.521410] kernel BUG at include/linux/mmap_lock.h:156!\n...........................................................\n[   62.538938] RIP: 0010:find_vma+0x32/0x80\n...........................................................\n[   62.605889] Call Trace:\n[   62.608502]  <TASK>\n[   62.610956]  ? lock_timer_base+0x61/0x80\n[   62.614106]  find_extend_vma+0x19/0x80\n[   62.617195]  __get_user_pages+0x9b/0x6a0\n[   62.620356]  __gup_longterm_locked+0x42d/0x450\n[   62.623721]  ? finish_wait+0x41/0x80\n[   62.626748]  ? __kmalloc+0x178/0x2f0\n[   62.629768]  ne_set_user_memory_region_ioctl.isra.0+0x225/0x6a0 [nitro_enclaves]\n[   62.635776]  ne_enclave_ioctl+0x1cf/0x6d7 [nitro_enclaves]\n[   62.639541]  __x64_sys_ioctl+0x82/0xb0\n[   62.642620]  do_syscall_64+0x3b/0x90\n[   62.645642]  entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nUse get_user_pages_unlocked() when setting the enclave memory regions.\nThat's a similar pattern as mmap_read_lock() used together with\nget_user_pages().","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-667"],"references":["https://git.kernel.org/stable/c/3a0152b219523227c2a62a0a122cf99608287176","https://git.kernel.org/stable/c/90d2beed5e753805c5eab656b8d48257638fe543","https://git.kernel.org/stable/c/3a0152b219523227c2a62a0a122cf99608287176","https://git.kernel.org/stable/c/90d2beed5e753805c5eab656b8d48257638fe543"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:45:59.823092188+00:00"},"epss":{"cve":"CVE-2021-46927","score":0.0015,"percentile":0.04144,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}