{"id":"CVE-2026-64596","summary":"libfs: set SB_I_NOEXEC and SB_I_NODEV by default in init_pseudo()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nlibfs: set SB_I_NOEXEC and SB_I_NODEV by default in init_pseudo()\n\nSince commit 1e7ab6f67824 (\"anon_inode: rework assertions\"),\npath_noexec() warns when an anonymous-inode file is mmap'd from a\nsuperblock that has not set SB_I_NOEXEC. dma-buf backs its files this\nway and never set the flag, so mmap of any exported buffer trips the\nwarning on a CONFIG_DEBUG_VFS=y kernel:\n\n  WARNING: CPU: 11 PID: 121813 at fs/exec.c:118 path_noexec+0x47/0x50\n   do_mmap+0x2b5/0x680\n   vm_mmap_pgoff+0x129/0x210\n   ksys_mmap_pgoff+0x177/0x240\n   __x64_sys_mmap+0x33/0x70\n\ninit_pseudo() sets up internal SB_NOUSER mounts that are never\npath-reachable. Set both flags here so every pseudo filesystem gets\nthem by default instead of each caller setting them.\n\nSB_I_NODEV is inert for unreachable mounts. SB_I_NOEXEC has one\nvisible effect: an executable mapping of a pseudo-fs fd, such as a\ndma-buf, now fails with -EPERM, which is the invariant the assertion\nenforces. No in-tree caller maps these executable.\n\nReproduce on CONFIG_DEBUG_VFS=y:\n\n  make -C tools/testing/selftests/dmabuf-heaps\n  sudo ./tools/testing/selftests/dmabuf-heaps/dmabuf-heap -t system","modified":"2026-10-08T02:51:31.132034094Z","published":"2026-08-06T07:13:51.523Z","related":["openSUSE-SU-2026:11476-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64596.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/6de2aeffabaafaeda819e60ec8d04f199711e11a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8e931557b317f0fb414839fa51fae1d5feb0ad97"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b9d45d328fcda4f0d3d281b7d6f12d3f181d9381"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64596.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64596"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"1e7ab6f67824343ee3e96f100f0937c393749a8a"},{"fixed":"b9d45d328fcda4f0d3d281b7d6f12d3f181d9381"},{"fixed":"8e931557b317f0fb414839fa51fae1d5feb0ad97"},{"fixed":"6de2aeffabaafaeda819e60ec8d04f199711e11a"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.15.6"},{"fixed":"6.16"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"9b8076a9404568d6cb6673b9a079558b15051966"}]}],"versions":["v6.15.11","v6.15.10","v6.15.9","v6.15.8","v6.15.7","v6.15.6"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64596.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.16.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64596.json"}}],"schema_version":"1.9.0"}