{"id":"CVE-2023-53846","summary":"f2fs: fix to do sanity check on direct node in truncate_dnode()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to do sanity check on direct node in truncate_dnode()\n\nsyzbot reports below bug:\n\nBUG: KASAN: slab-use-after-free in f2fs_truncate_data_blocks_range+0x122a/0x14c0 fs/f2fs/file.c:574\nRead of size 4 at addr ffff88802a25c000 by task syz-executor148/5000\n\nCPU: 1 PID: 5000 Comm: syz-executor148 Not tainted 6.4.0-rc7-syzkaller-00041-ge660abd551f1 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106\n print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351\n print_report mm/kasan/report.c:462 [inline]\n kasan_report+0x11c/0x130 mm/kasan/report.c:572\n f2fs_truncate_data_blocks_range+0x122a/0x14c0 fs/f2fs/file.c:574\n truncate_dnode+0x229/0x2e0 fs/f2fs/node.c:944\n f2fs_truncate_inode_blocks+0x64b/0xde0 fs/f2fs/node.c:1154\n f2fs_do_truncate_blocks+0x4ac/0xf30 fs/f2fs/file.c:721\n f2fs_truncate_blocks+0x7b/0x300 fs/f2fs/file.c:749\n f2fs_truncate.part.0+0x4a5/0x630 fs/f2fs/file.c:799\n f2fs_truncate include/linux/fs.h:825 [inline]\n f2fs_setattr+0x1738/0x2090 fs/f2fs/file.c:1006\n notify_change+0xb2c/0x1180 fs/attr.c:483\n do_truncate+0x143/0x200 fs/open.c:66\n handle_truncate fs/namei.c:3295 [inline]\n do_open fs/namei.c:3640 [inline]\n path_openat+0x2083/0x2750 fs/namei.c:3791\n do_filp_open+0x1ba/0x410 fs/namei.c:3818\n do_sys_openat2+0x16d/0x4c0 fs/open.c:1356\n do_sys_open fs/open.c:1372 [inline]\n __do_sys_creat fs/open.c:1448 [inline]\n __se_sys_creat fs/open.c:1442 [inline]\n __x64_sys_creat+0xcd/0x120 fs/open.c:1442\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nThe root cause is, inodeA references inodeB via inodeB's ino, once inodeA\nis truncated, it calls truncate_dnode() to truncate data blocks in inodeB's\nnode page, it traverse mapping data from node-\u003ei.i_addr[0] to\nnode-\u003ei.i_addr[ADDRS_PER_BLOCK() - 1], result in out-of-boundary access.\n\nThis patch fixes to add sanity check on dnode page in truncate_dnode(),\nso that, it can help to avoid triggering such issue, and once it encounters\nsuch issue, it will record newly introduced ERROR_INVALID_NODE_REFERENCE\nerror into superblock, later fsck can detect such issue and try repairing.\n\nAlso, it removes f2fs_truncate_data_blocks() for cleanup due to the\nfunction has only one caller, and uses f2fs_truncate_data_blocks_range()\ninstead.","modified":"2026-04-02T09:45:24.896043Z","published":"2025-12-09T01:30:09.202Z","related":["SUSE-SU-2026:0278-1","SUSE-SU-2026:0281-1","SUSE-SU-2026:0293-1","SUSE-SU-2026:0315-1","SUSE-SU-2026:20477-1","SUSE-SU-2026:20498-1","SUSE-SU-2026:20845-1","SUSE-SU-2026:20876-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53846.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/a6ec83786ab9f13f25fb18166dee908845713a95"},{"type":"WEB","url":"https://git.kernel.org/stable/c/af0f716ad3b039cab9d426da63a5ee6c88751185"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53846.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53846"},{"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":"98e4da8ca301e062d79ae168c67e56f3c3de3ce4"},{"fixed":"af0f716ad3b039cab9d426da63a5ee6c88751185"},{"fixed":"a6ec83786ab9f13f25fb18166dee908845713a95"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53846.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.8.0"},{"fixed":"6.4.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53846.json"}}],"schema_version":"1.7.5"}