GHSA-GM54-Q3XR-2X4R
Vulnerability from github – Published: 2026-04-22 15:31 – Updated: 2026-04-22 15:31In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix leak of kobject name for sub-group space_info
When create_space_info_sub_group() allocates elements of space_info->sub_group[], kobject_init_and_add() is called for each element via btrfs_sysfs_add_space_info_type(). However, when check_removing_space_info() frees these elements, it does not call btrfs_sysfs_remove_space_info() on them. As a result, kobject_put() is not called and the associated kobj->name objects are leaked.
This memory leak is reproduced by running the blktests test case zbd/009 on kernels built with CONFIG_DEBUG_KMEMLEAK. The kmemleak feature reports the following error:
unreferenced object 0xffff888112877d40 (size 16): comm "mount", pid 1244, jiffies 4294996972 hex dump (first 16 bytes): 64 61 74 61 2d 72 65 6c 6f 63 00 c4 c6 a7 cb 7f data-reloc...... backtrace (crc 53ffde4d): __kmalloc_node_track_caller_noprof+0x619/0x870 kstrdup+0x42/0xc0 kobject_set_name_vargs+0x44/0x110 kobject_init_and_add+0xcf/0x150 btrfs_sysfs_add_space_info_type+0xfc/0x210 [btrfs] create_space_info_sub_group.constprop.0+0xfb/0x1b0 [btrfs] create_space_info+0x211/0x320 [btrfs] btrfs_init_space_info+0x15a/0x1b0 [btrfs] open_ctree+0x33c7/0x4a50 [btrfs] btrfs_get_tree.cold+0x9f/0x1ee [btrfs] vfs_get_tree+0x87/0x2f0 vfs_cmd_create+0xbd/0x280 __do_sys_fsconfig+0x3df/0x990 do_syscall_64+0x136/0x1540 entry_SYSCALL_64_after_hwframe+0x76/0x7e
To avoid the leak, call btrfs_sysfs_remove_space_info() instead of kfree() for the elements.
{
"affected": [],
"aliases": [
"CVE-2026-31434"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-22T14:16:36Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix leak of kobject name for sub-group space_info\n\nWhen create_space_info_sub_group() allocates elements of\nspace_info-\u003esub_group[], kobject_init_and_add() is called for each\nelement via btrfs_sysfs_add_space_info_type(). However, when\ncheck_removing_space_info() frees these elements, it does not call\nbtrfs_sysfs_remove_space_info() on them. As a result, kobject_put() is\nnot called and the associated kobj-\u003ename objects are leaked.\n\nThis memory leak is reproduced by running the blktests test case\nzbd/009 on kernels built with CONFIG_DEBUG_KMEMLEAK. The kmemleak\nfeature reports the following error:\n\nunreferenced object 0xffff888112877d40 (size 16):\n comm \"mount\", pid 1244, jiffies 4294996972\n hex dump (first 16 bytes):\n 64 61 74 61 2d 72 65 6c 6f 63 00 c4 c6 a7 cb 7f data-reloc......\n backtrace (crc 53ffde4d):\n __kmalloc_node_track_caller_noprof+0x619/0x870\n kstrdup+0x42/0xc0\n kobject_set_name_vargs+0x44/0x110\n kobject_init_and_add+0xcf/0x150\n btrfs_sysfs_add_space_info_type+0xfc/0x210 [btrfs]\n create_space_info_sub_group.constprop.0+0xfb/0x1b0 [btrfs]\n create_space_info+0x211/0x320 [btrfs]\n btrfs_init_space_info+0x15a/0x1b0 [btrfs]\n open_ctree+0x33c7/0x4a50 [btrfs]\n btrfs_get_tree.cold+0x9f/0x1ee [btrfs]\n vfs_get_tree+0x87/0x2f0\n vfs_cmd_create+0xbd/0x280\n __do_sys_fsconfig+0x3df/0x990\n do_syscall_64+0x136/0x1540\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nTo avoid the leak, call btrfs_sysfs_remove_space_info() instead of\nkfree() for the elements.",
"id": "GHSA-gm54-q3xr-2x4r",
"modified": "2026-04-22T15:31:40Z",
"published": "2026-04-22T15:31:40Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31434"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1737ddeafbb1304f41ec2eede4f7366082e7c96a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3c645c6f7e5470debbb81666b230056de48f36dc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3c844d01f9874a43004c82970d8da94f9aba8949"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/416484f21a9d1280cf6daa7ebc10c79b59c46e48"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/94054ffd311a1f76b7093ba8ebf50bdb0d28337c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a4376d9a5d4c9610e69def3fc0b32c86a7ab7a41"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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