CVE-2021-47585

  1. Yack CVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-47585

5.5 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

I

n 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 }

References
Link Resource
https://git.kernel.org/stable/c/005d9292b5b2e71a009f911bd85d755009b37242 Patch
https://git.kernel.org/stable/c/493ff661d434d6bdf02e3a21adae04d7a0b4265d Patch
https://git.kernel.org/stable/c/f35838a6930296fc1988764cfa54cb3f705c0665 Patch
https://git.kernel.org/stable/c/005d9292b5b2e71a009f911bd85d755009b37242 Patch
https://git.kernel.org/stable/c/493ff661d434d6bdf02e3a21adae04d7a0b4265d Patch
https://git.kernel.org/stable/c/f35838a6930296fc1988764cfa54cb3f705c0665 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
History

21 Nov 2024, 06:36

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/005d9292b5b2e71a009f911bd85d755009b37242 - Patch () https://git.kernel.org/stable/c/005d9292b5b2e71a009f911bd85d755009b37242 - Patch
References () https://git.kernel.org/stable/c/493ff661d434d6bdf02e3a21adae04d7a0b4265d - Patch () https://git.kernel.org/stable/c/493ff661d434d6bdf02e3a21adae04d7a0b4265d - Patch
References () https://git.kernel.org/stable/c/f35838a6930296fc1988764cfa54cb3f705c0665 - Patch () https://git.kernel.org/stable/c/f35838a6930296fc1988764cfa54cb3f705c0665 - Patch

19 Aug 2024, 18:29

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
First Time Linux linux Kernel
Linux
CWE CWE-401
References () https://git.kernel.org/stable/c/005d9292b5b2e71a009f911bd85d755009b37242 - () https://git.kernel.org/stable/c/005d9292b5b2e71a009f911bd85d755009b37242 - Patch
References () https://git.kernel.org/stable/c/493ff661d434d6bdf02e3a21adae04d7a0b4265d - () https://git.kernel.org/stable/c/493ff661d434d6bdf02e3a21adae04d7a0b4265d - Patch
References () https://git.kernel.org/stable/c/f35838a6930296fc1988764cfa54cb3f705c0665 - () https://git.kernel.org/stable/c/f35838a6930296fc1988764cfa54cb3f705c0665 - Patch
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5

20 Jun 2024, 12:43

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se resolvió la siguiente vulnerabilidad: btrfs: corrige la pérdida de memoria en __add_inode_ref() La línea 1169 (#3) asigna un fragmento de memoria para victim_name mediante kmalloc(), pero cuando la función regresa en la línea 1184 (#4) victim_name asignado por la línea 1169 (#3) no se libera, lo que provocará una pérdida de memoria. Hay un fragmento de código similar en esta función para asignar un fragmento de memoria para victim_name en la línea 1104 (n.º 1), así como para liberar la memoria en la línea 1116 (n.º 2). Deberíamos kfree() victim_name cuando el valor de retorno de backref_in_log() sea menor que cero y antes de que la función regrese en la línea 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, 63 u64 inode_objectid, u64 parent_objectid, 1064 u64 ref_index, char *nombre, int nombrelen, 1065 int *search_done) 1066 { 1104 nombre_víctima = kmalloc(nombre_víctima_len, GFP_NOFS); // #1: kmalloc (nombre_víctima-1) 1105 if (!nombre_víctima) 1106 return -ENOMEM; 1112 ret = backref_in_log(log_root, &amp;search_key, 1113 parent_objectid, victim_name, 1114 victim_name_len); 1115 if (ret &lt; 0) { 1116 kfree(nombre_víctima); // #2: kfree (nombre_víctima-1) 1117 return ret; 1118 } else if (!ret) { 1169 nombre_víctima = kmalloc(nombre_víctima_len, GFP_NOFS); // #3: kmalloc (nombre_víctima-2) 1170 if (!nombre_víctima) 1171 return -ENOMEM; 1180 ret = backref_in_log(log_root, &amp;search_key, 1181 parent_objectid, victim_name, 1182 victim_name_len); 1183 si (ret &lt; 0) { 1184 retorno ret; // #4: falta kfree (nombre_víctima-2) 1185 } else if (!ret) { 1241 return 0; 1242 }

19 Jun 2024, 15:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-06-19 15:15

Updated : 2024-11-21 06:36

NVD link : CVE-2021-47585

Mitre link : CVE-2021-47585

CVE.ORG link : CVE-2021-47585

JSON object : View

Products Affected

linux

CWE
CWE-401

Missing Release of Memory after Effective Lifetime