cbcvebase.
CVE-2021-47638
published 2025-02-26

CVE-2021-47638: 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…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.26%
17.1th percentile
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

21 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.17.3-1 (bookworm)linux 5.17.3-1 (bookworm)
linuxlinux——
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < 8b3c7be16f3f4dfd6e15ac651484e59d3fa362748b3c7be16f3f4dfd6e15ac651484e59d3fa36274
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < 2b3236ecf96db7af5836e1366ce39ace8ce832fa2b3236ecf96db7af5836e1366ce39ace8ce832fa
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < 14276d38c89a170363e90b6ac0a53c3cf61b87fc14276d38c89a170363e90b6ac0a53c3cf61b87fc
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < a90e2dbe66d2647ff95a0442ad2e86482d977fd8a90e2dbe66d2647ff95a0442ad2e86482d977fd8
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < 2ad07009c459e56ebdcc089d850d664660fdb7422ad07009c459e56ebdcc089d850d664660fdb742
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < b9a937f096e608b3368c1abc920d4d640ba2c94fb9a937f096e608b3368c1abc920d4d640ba2c94f
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < 6d7a158a7363c1f6604aa47ae1a280a5c65123dd6d7a158a7363c1f6604aa47ae1a280a5c65123dd
linuxlinux>= 9e0a1fff8db56eaaebb74b4a3ef65f86811c4798 < 40a8f0d5e7b3999f096570edab71c345da812e3e40a8f0d5e7b3999f096570edab71c345da812e3e
linuxlinux_kernel>= 0 < 5.10.113-15.10.113-1
linuxlinux_kernel>= 0 < 5.17.3-15.17.3-1
linuxlinux_kernel>= 0 < 5.17.3-15.17.3-1
linuxlinux_kernel>= 0 < 5.17.3-15.17.3-1
linuxlinux_kernel>= 4.15 < 4.19.2384.19.238
linuxlinux_kernel>= 4.20 < 5.4.1895.4.189
linuxlinux_kernel>= 4.9 < 4.14.2764.14.276
linuxlinux_kernel>= 5.11 < 5.15.335.15.33
linuxlinux_kernel>= 5.16 < 5.16.195.16.19
linuxlinux_kernel>= 5.17 < 5.17.25.17.2
linuxlinux_kernel>= 5.5 < 5.10.1105.10.110

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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