CVE-2022-49271

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2022-49271
In the Linux kernel, the following vulnerability has been resolved: cifs: prevent bad output lengths in smb2_ioctl_query_info() When calling smb2_ioctl_query_info() with smb_query_info::flags=PASSTHRU_FSCTL and smb_query_info::output_buffer_length=0, the following would return 0x10 buffer = memdup_user(arg + sizeof(struct smb_query_info), qi.output_buffer_length); if (IS_ERR(buffer)) { kfree(vars); return PTR_ERR(buffer); } rather than a valid pointer thus making IS_ERR() check fail. This would then cause a NULL ptr deference in @buffer when accessing it later in smb2_ioctl_query_ioctl(). While at it, prevent having a @buffer smaller than 8 bytes to correctly handle SMB2_SET_INFO FileEndOfFileInformation requests when smb_query_info::flags=PASSTHRU_SET_INFO. Here is a small C reproducer which triggers a NULL ptr in @buffer when passing an invalid smb_query_info::flags #include <stdio.h> #include <stdlib.h> #include <stdint.h> #include <unistd.h> #include <fcntl.h> #include <sys/ioctl.h> #define die(s) perror(s), exit(1) #define QUERY_INFO 0xc018cf07 int main(int argc, char *argv[]) { int fd; if (argc < 2) exit(1); fd = open(argv[1], O_RDONLY); if (fd == -1) die("open"); if (ioctl(fd, QUERY_INFO, (uint32_t[]) { 0, 0, 0, 4, 0, 0}) == -1) die("ioctl"); close(fd); return 0; } mount.cifs //srv/share /mnt -o ... gcc repro.c && ./a.out /mnt/f0 [ 114.138620] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 114.139310] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] [ 114.139775] CPU: 2 PID: 995 Comm: a.out Not tainted 5.17.0-rc8 #1 [ 114.140148] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 [ 114.140818] RIP: 0010:smb2_ioctl_query_info+0x206/0x410 [cifs] [ 114.141221] Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 c8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 28 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9c 01 00 00 49 8b 3f e8 58 02 fb ff 48 8b 14 24 [ 114.142348] RSP: 0018:ffffc90000b47b00 EFLAGS: 00010256 [ 114.142692] RAX: dffffc0000000000 RBX: ffff888115503200 RCX: ffffffffa020580d [ 114.143119] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffa043a380 [ 114.143544] RBP: ffff888115503278 R08: 0000000000000001 R09: 0000000000000003 [ 114.143983] R10: fffffbfff4087470 R11: 0000000000000001 R12: ffff888115503288 [ 114.144424] R13: 00000000ffffffea R14: ffff888115503228 R15: 0000000000000000 [ 114.144852] FS: 00007f7aeabdf740(0000) GS:ffff888151600000(0000) knlGS:0000000000000000 [ 114.145338] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 114.145692] CR2: 00007f7aeacfdf5e CR3: 000000012000e000 CR4: 0000000000350ee0 [ 114.146131] Call Trace: [ 114.146291] <TASK> [ 114.146432] ? smb2_query_reparse_tag+0x890/0x890 [cifs] [ 114.146800] ? cifs_mapchar+0x460/0x460 [cifs] [ 114.147121] ? rcu_read_lock_sched_held+0x3f/0x70 [ 114.147412] ? cifs_strndup_to_utf16+0x15b/0x250 [cifs] [ 114.147775] ? dentry_path_raw+0xa6/0xf0 [ 114.148024] ? cifs_convert_path_to_utf16+0x198/0x220 [cifs] [ 114.148413] ? smb2_check_message+0x1080/0x1080 [cifs] [ 114.148766] ? rcu_read_lock_sched_held+0x3f/0x70 [ 114.149065] cifs_ioctl+0x1577/0x3320 [cifs] [ 114.149371] ? lock_downgrade+0x6f0/0x6f0 [ 114.149631] ? cifs_readdir+0x2e60/0x2e60 [cifs] [ 114.149956] ? rcu_read_lock_sched_held+0x3f/0x70 [ 114.150250] ? __rseq_handle_notify_resume+0x80b/0xbe0 [ 114.150562] ? __up_read+0x192/0x710 [ 114.150791] ? __ia32_sys_rseq+0xf0/0xf0 [ 114.151025] ? __x64_sys_openat+0x11f/0x1d0 [ 114.151296] __x64_sys_ioctl+0x127/0x190 [ 114.151549] do_syscall_64+0x3b/0x90 [ 114.151768] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 114.152079] RIP: 0033:0x7f7aead043df [ 114.152306] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 ---truncated---

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

References
Link Resource
https://git.kernel.org/stable/c/7529fbee10d82493c5cb109e51788bf74816d1c0 Patch
https://git.kernel.org/stable/c/9963ccea6087268e1275b992dca5d0dd4b938765 Patch
https://git.kernel.org/stable/c/b92e358757b91c2827af112cae9af513f26a3f34 Patch
https://git.kernel.org/stable/c/f143f8334fb9eb2f6c7c15b9da1472d9c965fd84 Patch
https://git.kernel.org/stable/c/fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53 Patch
Configurations

Configuration 1 (hide)

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

22 Sep 2025, 20:32

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
CWE CWE-476
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: cifs: evitar longitudes de salida incorrectas en smb2_ioctl_query_info() Al llamar a smb2_ioctl_query_info() con smb_query_info::flags=PASSTHRU_FSCTL y smb_query_info::output_buffer_length=0, lo siguiente devolvería 0x10 buffer = memdup_user(arg + sizeof(struct smb_query_info), qi.output_buffer_length); if (IS_ERR(buffer)) { kfree(vars); return PTR_ERR(buffer); } en lugar de un puntero válido, lo que hace que la comprobación de IS_ERR() falle. Esto provocaría una deferencia ptr NULL en @buffer al acceder a él más tarde en smb2_ioctl_query_ioctl(). Mientras tanto, evite tener un @buffer más pequeño que 8 bytes para manejar correctamente las solicitudes SMB2_SET_INFO FileEndOfFileInformation cuando smb_query_info::flags=PASSTHRU_SET_INFO. Aquí hay un pequeño reproductor de C que activa un ptr NULL en @buffer cuando pasa un smb_query_info::flags no válido #include #include #include #include #include #include #define die(s) perror(s), exit(1) #define QUERY_INFO 0xc018cf07 int main(int argc, char *argv[]) { int fd; if (argc &lt; 2) exit(1); fd = open(argv[1], O_RDONLY); si (fd == -1) morir("abrir"); si (ioctl(fd, QUERY_INFO, (uint32_t[]) { 0, 0, 0, 4, 0, 0}) == -1) morir("ioctl"); cerrar(fd); devolver 0; } mount.cifs //srv/share /mnt -o ... gcc repro.c &amp;&amp; ./a.out /mnt/f0 [ 114.138620] fallo de protección general, probablemente para dirección no canónica 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 114.139310] KASAN: null-ptr-deref en rango [0x000000000000000-0x0000000000000007] [ 114.139775] CPU: 2 PID: 995 Comm: a.out No contaminado 5.17.0-rc8 #1 [ 114.140148] Nombre del hardware: PC estándar QEMU (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 01/04/2014 [ 114.140818] RIP: 0010:smb2_ioctl_query_info+0x206/0x410 [cifs] [ 114.141221] Código: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 c8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 28 4c 89 fa 48 c1 ea 03 &lt;80&gt; 3c 02 00 0f 85 9c 01 00 00 49 8b 3f e8 58 02 fb ff 48 8b 14 24 [ 114.142348] RSP: 0018:ffffc90000b47b00 EFLAGS: 00010256 [ 114.142692] RAX: dffffc0000000000 RBX: ffff888115503200 RCX: fffffffa020580d [ 114.143119] RDX: 00000000000000000 RSI: 000000000000000004 RDI: fffffffa043a380 [ 114.143544] PBR: ffff888115503278 R08: 0000000000000001 R09: 00000000000000003 [ 114.143983] R10: fffffbfff4087470 R11: 0000000000000001 R12: ffff888115503288 [ 114.144424] R13: 00000000ffffffea R14: ffff888115503228 R15: 0000000000000000 [ 114.144852] FS: 00007f7aeabdf740(0000) GS:ffff888151600000(0000) knlGS:00000000000000000 [ 114.145338] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 114.145692] CR2: 00007f7aeacfdf5e CR3: 000000012000e000 CR4: 0000000000350ee0 [ 114.146131] Seguimiento de llamadas: [ 114.146291] [ 114.146432] ? smb2_query_reparse_tag+0x890/0x890 [cifs] [ 114.146800] ? cifs_mapchar+0x460/0x460 [cifs] [ 114.147121] ? rcu_read_lock_sched_held+0x3f/0x70 [ 114.147412] ? cifs_strndup_to_utf16+0x15b/0x250 [cifs] [ 114.147775] ? dentry_path_raw+0xa6/0xf0 [ 114.148024] ? cifs_convert_path_to_utf16+0x198/0x220 [cifs] [ 114.148413] ? smb2_check_message+0x1080/0x1080 [cifs] [ 114.148766] ? rcu_read_lock_sched_held+0x3f/0x70 [ 114.149065] cifs_ioctl+0x1577/0x3320 [cifs] [ 114.149371] ? lock_downgrade+0x6f0/0x6f0 [ 114.149631] ? cifs_readdir+0x2e60/0x2e60 [cifs] [ 114.149956] ? rcu_read_lock_sched_held+0x3f/0x70 [ 114.150250] ? __rseq_handle_notify_resume+0x80b/0xbe0 [ 114.150562] ? __up_read+0x192/0x710 [ 114.150791] ? __ia32_sys_rseq+0xf0/0xf0 [ 114.151025] ? __x64_sys_openat+0x11f/0x1d0 [ 114.151296] __x64_sys_ioctl+0x127/0x190 [ 114.151549] do_syscall_64+0x3b/0x90 [ 114.151768] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 114.152079] RIP: 0033:0x7f7aead043df [ 114.152306] Código: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 ---truncado---
First Time Linux
Linux linux Kernel
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/7529fbee10d82493c5cb109e51788bf74816d1c0 - () https://git.kernel.org/stable/c/7529fbee10d82493c5cb109e51788bf74816d1c0 - Patch
References () https://git.kernel.org/stable/c/9963ccea6087268e1275b992dca5d0dd4b938765 - () https://git.kernel.org/stable/c/9963ccea6087268e1275b992dca5d0dd4b938765 - Patch
References () https://git.kernel.org/stable/c/b92e358757b91c2827af112cae9af513f26a3f34 - () https://git.kernel.org/stable/c/b92e358757b91c2827af112cae9af513f26a3f34 - Patch
References () https://git.kernel.org/stable/c/f143f8334fb9eb2f6c7c15b9da1472d9c965fd84 - () https://git.kernel.org/stable/c/f143f8334fb9eb2f6c7c15b9da1472d9c965fd84 - Patch
References () https://git.kernel.org/stable/c/fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53 - () https://git.kernel.org/stable/c/fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53 - Patch

26 Feb 2025, 07:01

Type Values Removed Values Added
New CVE
Information

Published : 2025-02-26 07:01

Updated : 2025-09-22 20:32

NVD link : CVE-2022-49271

Mitre link : CVE-2022-49271

CVE.ORG link : CVE-2022-49271

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-476

NULL Pointer Dereference