Synopsis
The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.
Description
The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.
- In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix potential deadlock with newly created symlinks Syzbot reported that page_symlink(), called by nilfs_symlink(), triggers memory reclamation involving the filesystem layer, which can result in circular lock dependencies among the reader/writer semaphore nilfs->ns_segctor_sem, s_writers percpu_rwsem (intwrite) and the fs_reclaim pseudo lock. This is because after commit 21fc61c73c39 (don't put symlink bodies in pagecache into highmem), the gfp flags of the page cache for symbolic links are overwritten to GFP_KERNEL via inode_nohighmem().
This is not a problem for symlinks read from the backing device, because the __GFP_FS flag is dropped after inode_nohighmem() is called. However, when a new symlink is created with nilfs_symlink(), the gfp flags remain overwritten to GFP_KERNEL. Then, memory allocation called from page_symlink() etc. triggers memory reclamation including the FS layer, which may call nilfs_evict_inode() or nilfs_dirty_inode(). And these can cause a deadlock if they are called while nilfs->ns_segctor_sem is held: Fix this issue by dropping the __GFP_FS flag from the page cache GFP flags of newly created symlinks in the same way that nilfs_new_inode() and __nilfs_read_inode() do, as a workaround until we adopt nofs allocation scope consistently or improve the locking constraints. (CVE-2024-50229)
Note that Nessus relies on the presence of the package as reported by the vendor.
Solution
There is no known solution at this time.
Plugin Details
File Name: unpatched_CVE_2024_50229.nasl
Agent: unix
Supported Sensors: Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched
Exploit Ease: No known exploits are available
Vulnerability Publication Date: 11/9/2024