CVE-ID

CVE-2024-35870

• CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in smb2_reconnect_server() The UAF bug is due to smb2_reconnect_server() accessing a session that is already being teared down by another thread that is executing __cifs_put_smb_ses(). This can happen when (a) the client has connection to the server but no session or (b) another thread ends up setting @ses->ses_status again to something different than SES_EXITING. To fix this, we need to make sure to unconditionally set @ses->ses_status to SES_EXITING and prevent any other threads from setting a new status while we're still tearing it down. The following can be reproduced by adding some delay to right after the ipc is freed in __cifs_put_smb_ses() - which will give smb2_reconnect_server() worker a chance to run and then accessing @ses->ipc: kinit ... mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10 [disconnect srv] ls /mnt/1 &>/dev/null sleep 30 kdestroy [reconnect srv] sleep 10 umount /mnt/1 ... CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed CIFS: VFS: \\srv Send error in SessSetup = -126 CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed CIFS: VFS: \\srv Send error in SessSetup = -126 general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 04/01/2014 Workqueue: cifsiod smb2_reconnect_server [cifs] RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0 Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75 7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8 RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83 RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800 RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000 R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000 FS: 0000000000000000(0000) GS:ffff888157c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> ? die_addr+0x36/0x90 ? exc_general_protection+0x1c1/0x3f0 ? asm_exc_general_protection+0x26/0x30 ? __list_del_entry_valid_or_report+0x33/0xf0 __cifs_put_smb_ses+0x1ae/0x500 [cifs] smb2_reconnect_server+0x4ed/0x710 [cifs] process_one_work+0x205/0x6b0 worker_thread+0x191/0x360 ? __pfx_worker_thread+0x10/0x10 kthread+0xe2/0x110 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x34/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK>
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
Assigning CNA
kernel.org
Date Record Created
20240517 Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20240517)
Votes (Legacy)
Comments (Legacy)
Proposed (Legacy)
N/A
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