GHSA-RVGW-688X-X595
Vulnerability from github – Published: 2024-10-21 18:30 – Updated: 2025-11-04 00:31In the Linux kernel, the following vulnerability has been resolved:
cachefiles: fix dentry leak in cachefiles_open_file()
A dentry leak may be caused when a lookup cookie and a cull are concurrent:
P1 | P2
cachefiles_lookup_cookie cachefiles_look_up_object lookup_one_positive_unlocked // get dentry cachefiles_cull inode->i_flags |= S_KERNEL_FILE; cachefiles_open_file cachefiles_mark_inode_in_use __cachefiles_mark_inode_in_use can_use = false if (!(inode->i_flags & S_KERNEL_FILE)) can_use = true return false return false // Returns an error but doesn't put dentry
After that the following WARNING will be triggered when the backend folder is umounted:
================================================================== BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img} still in use (1) [unmount of ext4 sda] WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70 CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25 RIP: 0010:umount_check+0x5d/0x70 Call Trace: d_walk+0xda/0x2b0 do_one_tree+0x20/0x40 shrink_dcache_for_umount+0x2c/0x90 generic_shutdown_super+0x20/0x160 kill_block_super+0x1a/0x40 ext4_kill_sb+0x22/0x40 deactivate_locked_super+0x35/0x80 cleanup_mnt+0x104/0x160 ==================================================================
Whether cachefiles_open_file() returns true or false, the reference count obtained by lookup_positive_unlocked() in cachefiles_look_up_object() should be released.
Therefore release that reference count in cachefiles_look_up_object() to fix the above issue and simplify the code.
{
"affected": [],
"aliases": [
"CVE-2024-49870"
],
"database_specific": {
"cwe_ids": [
"CWE-401"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-10-21T18:15:08Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncachefiles: fix dentry leak in cachefiles_open_file()\n\nA dentry leak may be caused when a lookup cookie and a cull are concurrent:\n\n P1 | P2\n-----------------------------------------------------------\ncachefiles_lookup_cookie\n cachefiles_look_up_object\n lookup_one_positive_unlocked\n // get dentry\n cachefiles_cull\n inode-\u003ei_flags |= S_KERNEL_FILE;\n cachefiles_open_file\n cachefiles_mark_inode_in_use\n __cachefiles_mark_inode_in_use\n can_use = false\n if (!(inode-\u003ei_flags \u0026 S_KERNEL_FILE))\n can_use = true\n\t return false\n return false\n // Returns an error but doesn\u0027t put dentry\n\nAfter that the following WARNING will be triggered when the backend folder\nis umounted:\n\n==================================================================\nBUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img} still in use (1) [unmount of ext4 sda]\nWARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70\nCPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25\nRIP: 0010:umount_check+0x5d/0x70\nCall Trace:\n \u003cTASK\u003e\n d_walk+0xda/0x2b0\n do_one_tree+0x20/0x40\n shrink_dcache_for_umount+0x2c/0x90\n generic_shutdown_super+0x20/0x160\n kill_block_super+0x1a/0x40\n ext4_kill_sb+0x22/0x40\n deactivate_locked_super+0x35/0x80\n cleanup_mnt+0x104/0x160\n==================================================================\n\nWhether cachefiles_open_file() returns true or false, the reference count\nobtained by lookup_positive_unlocked() in cachefiles_look_up_object()\nshould be released.\n\nTherefore release that reference count in cachefiles_look_up_object() to\nfix the above issue and simplify the code.",
"id": "GHSA-rvgw-688x-x595",
"modified": "2025-11-04T00:31:40Z",
"published": "2024-10-21T18:30:56Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-49870"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7fa2382f97421978514a419c93054eca69f5247b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c7d10fa7d7691558ff967668494672415f5fa151"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d32ff64c872d7e08e893c32ba6a2374583444410"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/da6ef2dffe6056aad3435e6cf7c6471c2a62187c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e4a28489b310339b2b8187bec0a437709be551c1"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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