# CVE-2021-47585: linux: In the Linux kernel, the following vulnerability has been resolved:  btrfs: fix memory leak in __add_inode_ref()  Lin...

CVE-2021-47585 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47585, released June 19, 2024. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-47585
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0025
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 19, 2024

## Description

In the Linux kernel, the following vulnerability has been resolved:  btrfs: fix memory leak in __add_inode_ref()  Line 1169 (#3) allocates a memory chunk for victim_name by kmalloc(), but  when the function returns in line 1184 (#4) victim_name allocated by line 1169 (#3) is not freed, which will lead to a memory leak. There is a similar snippet of code in this function as allocating a memory chunk for victim_name in line 1104 (#1) as well as releasing the memory in line 1116 (#2).  We should kfree() victim_name when the return value of backref_in_log() is less than zero and before the function returns in line 1184 (#4).  1057 static inline int __add_inode_ref(struct btrfs_trans_handle *trans, 1058 				  struct btrfs_root *root, 1059 				  struct btrfs_path *path, 1060 				  struct btrfs_root *log_root, 1061 				  struct btrfs_inode *dir, 1062 				  struct btrfs_inode *inode, 1063 				  u64 inode_objectid, u64 parent_objectid, 1064 				  u64 ref_index, char *name, int namelen, 1065 				  int *search_done) 1066 {  1104 	victim_name = kmalloc(victim_name_len, GFP_NOFS); 	// #1: kmalloc (victim_name-1) 1105 	if (!victim_name) 1106 		return -ENOMEM;  1112	ret = backref_in_log(log_root, &search_key, 1113			parent_objectid, victim_name, 1114			victim_name_len); 1115	if (ret < 0) { 1116		kfree(victim_name); // #2: kfree (victim_name-1) 1117		return ret; 1118	} else if (!ret) {  1169 	victim_name = kmalloc(victim_name_len, GFP_NOFS); 	// #3: kmalloc (victim_name-2) 1170 	if (!victim_name) 1171 		return -ENOMEM;  1180 	ret = backref_in_log(log_root, &search_key, 1181 			parent_objectid, victim_name, 1182 			victim_name_len); 1183 	if (ret < 0) { 1184 		return ret; // #4: missing kfree (victim_name-2) 1185 	} else if (!ret) {  1241 	return 0; 1242 }

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.15.15-1 | [DEBIAN-CVE-2021-47585](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47585.md) | Jun 19, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.15.15-1 | [DEBIAN-CVE-2021-47585](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47585.md) | Jun 19, 2024 |
| Linux | linux Debian 14 | 5.15.15-1 | [DEBIAN-CVE-2021-47585](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47585.md) | Jun 19, 2024 |

---

Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.