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CVE PROGRAM SOURCE RECORD7.8 High

CVE-2021-47638

ubifs: rename_whiteout: Fix double free for whiteout_ui->data

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Status
Published
Published
Updated
Assigning organization
Linux

Description

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).

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < 8b3c7be16f3f4dfd6e15ac651484e59d3fa36274affected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < 2b3236ecf96db7af5836e1366ce39ace8ce832faaffected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < 14276d38c89a170363e90b6ac0a53c3cf61b87fcaffected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < a90e2dbe66d2647ff95a0442ad2e86482d977fd8affected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < 2ad07009c459e56ebdcc089d850d664660fdb742affected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < b9a937f096e608b3368c1abc920d4d640ba2c94faffected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < 6d7a158a7363c1f6604aa47ae1a280a5c65123ddaffected
  • 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 to < 40a8f0d5e7b3999f096570edab71c345da812e3eaffected

Linux Linux

Default version status: affected

  • 4.9affected
  • 0 to < 4.9unaffected
  • 4.14.276 to ≤ 4.14.*unaffected
  • 4.19.238 to ≤ 4.19.*unaffected
  • 5.4.189 to ≤ 5.4.*unaffected
  • 5.10.110 to ≤ 5.10.*unaffected
  • 5.15.33 to ≤ 5.15.*unaffected
  • 5.16.19 to ≤ 5.16.*unaffected
  • 5.17.2 to ≤ 5.17.*unaffected
  • 5.18 to ≤ *unaffected

References