{"id":"CVE-2022-49347","summary":"ext4: fix bug_on in ext4_writepages","details":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix bug_on in ext4_writepages\n\nwe got issue as follows:\nEXT4-fs error (device loop0): ext4_mb_generate_buddy:1141: group 0, block bitmap and bg descriptor inconsistent: 25 vs 31513 free cls\n------------[ cut here ]------------\nkernel BUG at fs/ext4/inode.c:2708!\ninvalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI\nCPU: 2 PID: 2147 Comm: rep Not tainted 5.18.0-rc2-next-20220413+ #155\nRIP: 0010:ext4_writepages+0x1977/0x1c10\nRSP: 0018:ffff88811d3e7880 EFLAGS: 00010246\nRAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88811c098000\nRDX: 0000000000000000 RSI: ffff88811c098000 RDI: 0000000000000002\nRBP: ffff888128140f50 R08: ffffffffb1ff6387 R09: 0000000000000000\nR10: 0000000000000007 R11: ffffed10250281ea R12: 0000000000000001\nR13: 00000000000000a4 R14: ffff88811d3e7bb8 R15: ffff888128141028\nFS:  00007f443aed9740(0000) GS:ffff8883aef00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000020007200 CR3: 000000011c2a4000 CR4: 00000000000006e0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n \u003cTASK\u003e\n do_writepages+0x130/0x3a0\n filemap_fdatawrite_wbc+0x83/0xa0\n filemap_flush+0xab/0xe0\n ext4_alloc_da_blocks+0x51/0x120\n __ext4_ioctl+0x1534/0x3210\n __x64_sys_ioctl+0x12c/0x170\n do_syscall_64+0x3b/0x90\n\nIt may happen as follows:\n1. write inline_data inode\nvfs_write\n  new_sync_write\n    ext4_file_write_iter\n      ext4_buffered_write_iter\n        generic_perform_write\n          ext4_da_write_begin\n            ext4_da_write_inline_data_begin -\u003e If inline data size too\n            small will allocate block to write, then mapping will has\n            dirty page\n                ext4_da_convert_inline_data_to_extent -\u003eclear EXT4_STATE_MAY_INLINE_DATA\n2. fallocate\ndo_vfs_ioctl\n  ioctl_preallocate\n    vfs_fallocate\n      ext4_fallocate\n        ext4_convert_inline_data\n          ext4_convert_inline_data_nolock\n            ext4_map_blocks -\u003e fail will goto restore data\n            ext4_restore_inline_data\n              ext4_create_inline_data\n              ext4_write_inline_data\n              ext4_set_inode_state -\u003e set inode EXT4_STATE_MAY_INLINE_DATA\n3. writepages\n__ext4_ioctl\n  ext4_alloc_da_blocks\n    filemap_flush\n      filemap_fdatawrite_wbc\n        do_writepages\n          ext4_writepages\n            if (ext4_has_inline_data(inode))\n              BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))\n\nThe root cause of this issue is we destory inline data until call\next4_writepages under delay allocation mode.  But there maybe already\nconvert from inline to extent.  To solve this issue, we call\nfilemap_flush first..","modified":"2026-04-02T08:27:31.022188Z","published":"2025-02-26T02:11:01.983Z","related":["SUSE-SU-2025:1027-1","SUSE-SU-2025:1176-1","SUSE-SU-2025:1183-1","SUSE-SU-2025:1194-1","SUSE-SU-2025:1241-1","SUSE-SU-2025:1263-1","SUSE-SU-2025:1293-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49347.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/013f12bdedb96816aaa27ee04349f4433d361f52"},{"type":"WEB","url":"https://git.kernel.org/stable/c/18a759f7f99f0b65a08ff5b7e745fc405a42bde4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/19918ec7717d87d5ab825884a46b26b21375d7ce"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1b061af037646c9cdb0afd8a8d2f1e1c06285866"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1cde35417edc0370fb0179a4e38b78a15350a8d0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/73fd5b19285197078ee8a2e651d75d5b094a4de9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b2b78f5bf2d453dda3903955efee059260787a42"},{"type":"WEB","url":"https://git.kernel.org/stable/c/de1732b5c1693ad489c5d254f124f67cb775f37d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ef09ed5d37b84d18562b30cf7253e57062d0db05"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49347.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-49347"},{"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":"3c47d54170b6a678875566b1b8d6dcf57904e49b"},{"fixed":"19918ec7717d87d5ab825884a46b26b21375d7ce"},{"fixed":"b2b78f5bf2d453dda3903955efee059260787a42"},{"fixed":"de1732b5c1693ad489c5d254f124f67cb775f37d"},{"fixed":"73fd5b19285197078ee8a2e651d75d5b094a4de9"},{"fixed":"1b061af037646c9cdb0afd8a8d2f1e1c06285866"},{"fixed":"18a759f7f99f0b65a08ff5b7e745fc405a42bde4"},{"fixed":"1cde35417edc0370fb0179a4e38b78a15350a8d0"},{"fixed":"013f12bdedb96816aaa27ee04349f4433d361f52"},{"fixed":"ef09ed5d37b84d18562b30cf7253e57062d0db05"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49347.json"}}],"schema_version":"1.7.5"}