{"id":"DEBIAN-CVE-2023-53485","details":"In the Linux kernel, the following vulnerability has been resolved:  fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev  Syzkaller reported the following issue:  UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:1965:6 index -84 is out of range for type 's8[341]' (aka 'signed char[341]') CPU: 1 PID: 4995 Comm: syz-executor146 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace:  \u003cTASK\u003e  __dump_stack lib/dump_stack.c:88 [inline]  dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106  ubsan_epilogue lib/ubsan.c:217 [inline]  __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348  dbAllocDmapLev+0x3e5/0x430 fs/jfs/jfs_dmap.c:1965  dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1809  dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1350  dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:874  dtSplitUp fs/jfs/jfs_dtree.c:974 [inline]  dtInsert+0xda7/0x6b00 fs/jfs/jfs_dtree.c:863  jfs_create+0x7b6/0xbb0 fs/jfs/namei.c:137  lookup_open fs/namei.c:3492 [inline]  open_last_lookups fs/namei.c:3560 [inline]  path_openat+0x13df/0x3170 fs/namei.c:3788  do_filp_open+0x234/0x490 fs/namei.c:3818  do_sys_openat2+0x13f/0x500 fs/open.c:1356  do_sys_open fs/open.c:1372 [inline]  __do_sys_openat fs/open.c:1388 [inline]  __se_sys_openat fs/open.c:1383 [inline]  __x64_sys_openat+0x247/0x290 fs/open.c:1383  do_syscall_x64 arch/x86/entry/common.c:50 [inline]  do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80  entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1f4e33f7e9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc21129578 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1f4e33f7e9 RDX: 000000000000275a RSI: 0000000020000040 RDI: 00000000ffffff9c RBP: 00007f1f4e2ff080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1f4e2ff110 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000  \u003c/TASK\u003e  The bug occurs when the dbAllocDmapLev()function attempts to access dp-\u003etree.stree[leafidx + LEAFIND] while the leafidx value is negative.  To rectify this, the patch introduces a safeguard within the dbAllocDmapLev() function. A check has been added to verify if leafidx is negative. If it is, the function immediately returns an I/O error, preventing any further execution that could potentially cause harm.  Tested via syzbot.","modified":"2026-09-15T09:02:51.374492403Z","published":"2025-10-01T12:15:51.330Z","upstream":["CVE-2023-53485"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2023-53485"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.52-1"}]}],"versions":["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"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-53485.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-53485.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-53485.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:H/A:H"}]}