Bug 1221572 (CVE-2021-47115)

Summary: VUL-0: REJECTED: CVE-2021-47115: kernel: nfc: fix NULL ptr dereference in llcp_sock_getname() after failed connect
Product: [Novell Products] SUSE Security Incidents Reporter: SMASH SMASH <smash_bz>
Component: IncidentsAssignee: Kernel Bugs <kernel-bugs>
Status: RESOLVED INVALID QA Contact: Security Team bot <security-team>
Severity: Normal    
Priority: P3 - Medium CC: rfrohl
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/397849/
Whiteboard: CVSSv3.1:SUSE:CVE-2021-47115:5.5:(AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Found By: Security Response Team Services Priority:
Business Priority: Blocker: ---
Marketing QA Status: --- IT Deployment: ---

Description SMASH SMASH 2024-03-18 10:04:00 UTC 
In the Linux kernel, the following vulnerability has been resolved:

nfc: fix NULL ptr dereference in llcp_sock_getname() after failed connect

It's possible to trigger NULL pointer dereference by local unprivileged
user, when calling getsockname() after failed bind() (e.g. the bind
fails because LLCP_SAP_MAX used as SAP):

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  CPU: 1 PID: 426 Comm: llcp_sock_getna Not tainted 5.13.0-rc2-next-20210521+ #9
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1 04/01/2014
  Call Trace:
   llcp_sock_getname+0xb1/0xe0
   __sys_getpeername+0x95/0xc0
   ? lockdep_hardirqs_on_prepare+0xd5/0x180
   ? syscall_enter_from_user_mode+0x1c/0x40
   __x64_sys_getpeername+0x11/0x20
   do_syscall_64+0x36/0x70
   entry_SYSCALL_64_after_hwframe+0x44/0xae

This can be reproduced with Syzkaller C repro (bind followed by
getpeername):
https://syzkaller.appspot.com/x/repro.c?x=14def446e00000

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-47115
https://www.cve.org/CVERecord?id=CVE-2021-47115
https://git.kernel.org/stable/c/0c4559736d9a4ec1ca58ba98ca34e7c4da4c422b
https://git.kernel.org/stable/c/39c15bd2e5d11bcf7f4c3dba2aad9e1e110a5d94
https://git.kernel.org/stable/c/48ee0db61c8299022ec88c79ad137f290196cac2
https://git.kernel.org/stable/c/4ac06a1e013cf5fdd963317ffd3b968560f33bba
https://git.kernel.org/stable/c/5d4c4b06ed9fb7a69d0b2e2a73fc73226d25ab70
https://git.kernel.org/stable/c/93e4ac2a9979a9a4ecc158409ed9c3044dc0ae1f
https://git.kernel.org/stable/c/eb6875d48590d8e564092e831ff07fa384d7e477
https://git.kernel.org/stable/c/ffff05b9ee5c74c04bba2801c1f99b31975d74d9
https://bugzilla.redhat.com/show_bug.cgi?id=2269863
Comment 1 Robert Frohl 2024-03-18 10:13:31 UTC 
looks like a duplicate of CVE-2021-38208/bsc#1187055