{"id":"DEBIAN-CVE-2025-37739","details":"In the Linux kernel, the following vulnerability has been resolved:  f2fs: fix to avoid out-of-bounds access in f2fs_truncate_inode_blocks()  syzbot reports an UBSAN issue as below:  ------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in fs/f2fs/node.h:381:10 index 18446744073709550692 is out of range for type '__le32[5]' (aka 'unsigned int[5]') CPU: 0 UID: 0 PID: 5318 Comm: syz.0.0 Not tainted 6.14.0-rc3-syzkaller-00060-g6537cfb395f3 #0 Call Trace:  \u003cTASK\u003e  __dump_stack lib/dump_stack.c:94 [inline]  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120  ubsan_epilogue lib/ubsan.c:231 [inline]  __ubsan_handle_out_of_bounds+0x121/0x150 lib/ubsan.c:429  get_nid fs/f2fs/node.h:381 [inline]  f2fs_truncate_inode_blocks+0xa5e/0xf60 fs/f2fs/node.c:1181  f2fs_do_truncate_blocks+0x782/0x1030 fs/f2fs/file.c:808  f2fs_truncate_blocks+0x10d/0x300 fs/f2fs/file.c:836  f2fs_truncate+0x417/0x720 fs/f2fs/file.c:886  f2fs_file_write_iter+0x1bdb/0x2550 fs/f2fs/file.c:5093  aio_write+0x56b/0x7c0 fs/aio.c:1633  io_submit_one+0x8a7/0x18a0 fs/aio.c:2052  __do_sys_io_submit fs/aio.c:2111 [inline]  __se_sys_io_submit+0x171/0x2e0 fs/aio.c:2081  do_syscall_x64 arch/x86/entry/common.c:52 [inline]  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83  entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f238798cde9  index 18446744073709550692 (decimal, unsigned long long) = 0xfffffffffffffc64 (hexadecimal, unsigned long long) = -924 (decimal, long long)  In f2fs_truncate_inode_blocks(), UBSAN detects that get_nid() tries to access .i_nid[-924], it means both offset[0] and level should zero.  The possible case should be in f2fs_do_truncate_blocks(), we try to truncate inode size to zero, however, dn.ofs_in_node is zero and dn.node_page is not an inode page, so it fails to truncate inode page, and then pass zeroed free_from to f2fs_truncate_inode_blocks(), result in this issue.  \tif (dn.ofs_in_node || IS_INODE(dn.node_page)) { \t\tf2fs_truncate_data_blocks_range(&dn, count); \t\tfree_from += count; \t}  I guess the reason why dn.node_page is not an inode page could be: there are multiple nat entries share the same node block address, once the node block address was reused, f2fs_get_node_page() may load a non-inode block.  Let's add a sanity check for such condition to avoid out-of-bounds access issue.","modified":"2026-09-01T20:05:46.216864641Z","published":"2025-05-01T13:15:52.500Z","upstream":["CVE-2025-37739"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-37739"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.135-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.123-1","6.1.124-1","6.1.128-1","6.1.129-1","6.1.133-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-37739.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-37739.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-37739.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"}]}