{"schema_version":"1.9.0","id":"CVE-2023-53247","published":"2025-09-15T14:46:17.344Z","modified":"2026-08-12T03:51:31.052517665Z","related":["SUSE-SU-2025:03600-1","SUSE-SU-2025:03634-1","SUSE-SU-2025:20851-1","SUSE-SU-2025:20861-1","SUSE-SU-2025:20870-1","SUSE-SU-2025:20898-1","SUSE-SU-2025:3751-1","SUSE-SU-2025:4057-1","SUSE-SU-2025:4132-1","SUSE-SU-2025:4141-1"],"summary":"btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand\n\nWhile trying to get the subpage blocksize tests running, I hit the\nfollowing panic on generic/476\n\n  assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229\n  kernel BUG at fs/btrfs/subpage.c:229!\n  Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n  CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12\n  Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023\n  pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)\n  pc : btrfs_subpage_assert+0xbc/0xf0\n  lr : btrfs_subpage_assert+0xbc/0xf0\n  Call trace:\n   btrfs_subpage_assert+0xbc/0xf0\n   btrfs_subpage_clear_checked+0x38/0xc0\n   btrfs_page_clear_checked+0x48/0x98\n   btrfs_truncate_block+0x5d0/0x6a8\n   btrfs_cont_expand+0x5c/0x528\n   btrfs_write_check.isra.0+0xf8/0x150\n   btrfs_buffered_write+0xb4/0x760\n   btrfs_do_write_iter+0x2f8/0x4b0\n   btrfs_file_write_iter+0x1c/0x30\n   do_iter_readv_writev+0xc8/0x158\n   do_iter_write+0x9c/0x210\n   vfs_iter_write+0x24/0x40\n   iter_file_splice_write+0x224/0x390\n   direct_splice_actor+0x38/0x68\n   splice_direct_to_actor+0x12c/0x260\n   do_splice_direct+0x90/0xe8\n   generic_copy_file_range+0x50/0x90\n   vfs_copy_file_range+0x29c/0x470\n   __arm64_sys_copy_file_range+0xcc/0x498\n   invoke_syscall.constprop.0+0x80/0xd8\n   do_el0_svc+0x6c/0x168\n   el0_svc+0x50/0x1b0\n   el0t_64_sync_handler+0x114/0x120\n   el0t_64_sync+0x194/0x198\n\nThis happens because during btrfs_cont_expand we'll get a page, set it\nas mapped, and if it's not Uptodate we'll read it.  However between the\nread and re-locking the page we could have called release_folio() on the\npage, but left the page in the file mapping.  release_folio() can clear\nthe page private, and thus further down we blow up when we go to modify\nthe subpage bits.\n\nFix this by putting the set_page_extent_mapped() after the read.  This\nis safe because read_folio() will call set_page_extent_mapped() before\nit does the read, and then if we clear page private but leave it on the\nmapping we're completely safe re-setting set_page_extent_mapped().  With\nthis patch I can now run generic/476 without panicing.","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"32443de3382be98c0a8b8f6f50d23da2e10c4117"},{"fixed":"0a5e0bc8e8618e32a6ca64450867628eb0a627bf"},{"fixed":"a5880e69cf7fe4a0bb1eabae02205352d1b59b7b"},{"fixed":"17b17fcd6d446b95904a6929c40012ee7f0afc0c"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53247.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.12.0"},{"fixed":"6.1.42"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.4.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53247.json"}}],"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0a5e0bc8e8618e32a6ca64450867628eb0a627bf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/17b17fcd6d446b95904a6929c40012ee7f0afc0c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a5880e69cf7fe4a0bb1eabae02205352d1b59b7b"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53247.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53247"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53247.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}