Answer in brief
CVE-2021-47638 records a High severity (CVSS 7.8) vulnerability in ubifs: rename_whiteout: Fix double free for whiteout_ui->data. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <8b3c7be16f3f4dfd6e15ac651484e59d3fa36274 || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <2b3236ecf96db7af5836e1366ce39ace8ce832fa || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <14276d38c89a170363e90b6ac0a53c3cf61b87fc || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <a90e2dbe66d2647ff95a0442ad2e86482d977fd8 || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <2ad07009c459e56ebdcc089d850d664660fdb742 || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <b9a937f096e608b3368c1abc920d4d640ba2c94f || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <6d7a158a7363c1f6604aa47ae1a280a5c65123dd || >=9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 <40a8f0d5e7b3999f096570edab71c345da812e3e | 8b3c7be16f3f4dfd6e15ac651484e59d3fa36274, 2b3236ecf96db7af5836e1366ce39ace8ce832fa, 14276d38c89a170363e90b6ac0a53c3cf61b87fc, a90e2dbe66d2647ff95a0442ad2e86482d977fd8, 2ad07009c459e56ebdcc089d850d664660fdb742, b9a937f096e608b3368c1abc920d4d640ba2c94f, 6d7a158a7363c1f6604aa47ae1a280a5c65123dd, 40a8f0d5e7b3999f096570edab71c345da812e3e |
| Linux/Linuxgeneric | 4.9 | Not reported |
Published upstream
Feb 26, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
In the Linux kernel, the following vulnerability has been resolved: ubifs: rename_whiteout: Fix double free for whiteout_ui->data 'whiteout_ui->data' will be freed twice if space budget fail for rename whiteout operation as following process: rename_whiteout dev = kmalloc whiteout_ui->data = dev kfree(whiteout_ui->data) // Free first time iput(whiteout) ubifs_free_inode kfree(ui->data) // Double free! KASAN reports: ================================================================== BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70 Call Trace: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f Allocated by task 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 Freed by task 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8 ================================================================== Let ubifs_free_inode() free 'whiteout_ui->data'. BTW, delete unused assignment 'whiteout_ui->data_len = 0', process 'ubifs_evict_inode() -> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode()' doesn't need it (because 'inc_nlink(whiteout)' won't be excuted by 'goto out_release', and the nlink of whiteout inode is 0).
Quoted source text, attributed separately from HOL analysis.