Import Source
https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-52070.json
JSON Data
https://api.test.osv.dev/v1/vulns/AZL-52070
Upstream
Published
2024-10-29T01:15:04Z
Modified
2026-04-01T05:26:31.842379Z
Severity
  • 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
CVE-2024-50073 affecting package kernel for versions less than 6.6.64.2-1
Details

In the Linux kernel, the following vulnerability has been resolved:

tty: ngsm: Fix use-after-free in gsmcleanup_mux

BUG: KASAN: slab-use-after-free in gsmcleanupmux+0x77b/0x7b0 drivers/tty/ngsm.c:3160 [ngsm] Read of size 8 at addr ffff88815fe99c00 by task poc/3379 CPU: 0 UID: 0 PID: 3379 Comm: poc Not tainted 6.11.0+ #56 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 Call Trace: <TASK> gsmcleanupmux+0x77b/0x7b0 drivers/tty/ngsm.c:3160 [ngsm] __pfxgsmcleanup_mux+0x10/0x10 drivers/tty/ngsm.c:3124 [ngsm] __pfxschedclock_cpu+0x10/0x10 kernel/sched/clock.c:389 updateloadavg+0x1c1/0x27b0 kernel/sched/fair.c:4500 __pfxminvruntimecbrotate+0x10/0x10 kernel/sched/fair.c:846 __rbinsertaugmented+0x492/0xbf0 lib/rbtree.c:161 gsmldioctl+0x395/0x1450 drivers/tty/ngsm.c:3408 [ngsm] rawspinlock_irqsave+0x92/0xf0 arch/x86/include/asm/atomic.h:107 __pfxgsmldioctl+0x10/0x10 drivers/tty/ngsm.c:3822 [ngsm] ktimeget+0x5e/0x140 kernel/time/timekeeping.c:195 ldsemdownread+0x94/0x4e0 arch/x86/include/asm/atomic6464.h:79 __pfxldsemdownread+0x10/0x10 drivers/tty/ttyldsem.c:338 _pfxdovfsioctl+0x10/0x10 fs/ioctl.c:805 ttyioctl+0x643/0x1100 drivers/tty/ttyio.c:2818

Allocated by task 65: gsmdataalloc.constprop.0+0x27/0x190 drivers/tty/ngsm.c:926 [ngsm] gsmsend+0x2c/0x580 drivers/tty/ngsm.c:819 [ngsm] gsm1receive+0x547/0xad0 drivers/tty/ngsm.c:3038 [ngsm] gsmldreceivebuf+0x176/0x280 drivers/tty/ngsm.c:3609 [ngsm] ttyldiscreceivebuf+0x101/0x1e0 drivers/tty/ttybuffer.c:391 ttyportdefaultreceivebuf+0x61/0xa0 drivers/tty/ttyport.c:39 flushtoldisc+0x1b0/0x750 drivers/tty/ttybuffer.c:445 processscheduledworks+0x2b0/0x10d0 kernel/workqueue.c:3229 workerthread+0x3dc/0x950 kernel/workqueue.c:3391 kthread+0x2a3/0x370 kernel/kthread.c:389 retfromfork+0x2d/0x70 arch/x86/kernel/process.c:147 retfromforkasm+0x1a/0x30 arch/x86/entry/entry_64.S:257

Freed by task 3367: kfree+0x126/0x420 mm/slub.c:4580 gsmcleanupmux+0x36c/0x7b0 drivers/tty/ngsm.c:3160 [ngsm] gsmldioctl+0x395/0x1450 drivers/tty/ngsm.c:3408 [ngsm] ttyioctl+0x643/0x1100 drivers/tty/tty_io.c:2818

[Analysis] gsmmsg on the txctrllist or txdatalist of gsmmux can be freed by multi threads through ioctl,which leads to the occurrence of uaf. Protect it by gsm tx lock.

References

Affected packages

Azure Linux:3 / kernel

Package

Name
kernel
Purl
pkg:rpm/azure-linux/kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
6.6.64.2-1

Database specific

source
"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-52070.json"