CVE-2024-44958: sched/smt: Fix unbalance sched_smt_present dec/inc
In the Linux kernel, the following vulnerability has been resolved:
sched/smt: Fix unbalance schedsmtpresent dec/inc
I got the following warn report while doing stress test:
jump label: negative count! WARNING: CPU: 3 PID: 38 at kernel/jumplabel.c:263 statickeyslowtrydec+0x9d/0xb0 Call Trace: <TASK> statickeyslowdeccpuslocked+0x16/0x70 schedcpudeactivate+0x26e/0x2a0 cpuhpinvokecallback+0x3ad/0x10d0 cpuhpthreadfun+0x3f5/0x680 smpbootthreadfn+0x56d/0x8d0 kthread+0x309/0x400 retfromfork+0x41/0x70 retfromforkasm+0x1b/0x30 </TASK>
Because when cpusetcpuinactive() fails in schedcpudeactivate(), the cpu offline failed, but schedsmtpresent is decremented before calling schedcpudeactivate(), it leads to unbalanced dec/inc, so fix it by incrementing schedsmtpresent in the error path.
Other sources
In the Linux kernel, the following vulnerability has been resolved:
sched/smt: Fix unbalance schedsmtpresent dec/inc
I got the following warn report while doing stress test:
jump label: negative count! WARNING: CPU: 3 PID: 38 at kernel/jumplabel.c:263 statickeyslowtrydec+0x9d/0xb0 Call Trace: <TASK> statickeyslowdeccpuslocked+0x16/0x70 schedcpudeactivate+0x26e/0x2a0 cpuhpinvokecallback+0x3ad/0x10d0 cpuhpthreadfun+0x3f5/0x680 smpbootthreadfn+0x56d/0x8d0 kthread+0x309/0x400 retfromfork+0x41/0x70 retfromforkasm+0x1b/0x30 </TASK>
Because when cpusetcpuinactive() fails in schedcpudeactivate(), the cpu offline failed, but schedsmtpresent is decremented before calling schedcpudeactivate(), it leads to unbalanced dec/inc, so fix it by incrementing schedsmtpresent in the error path.
— NVD
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1 - Upgrade
Upgrade
debian/linux-6.1to a version that resolves this vulnerability.Fixed in 6.1.129-1~deb11u1
Event History
Frequently Asked Questions
What is the severity of CVE-2024-44958?
CVE-2024-44958 does not have a publicly assigned severity rating but relates to potential balancing issues in the Linux kernel.
How do I fix CVE-2024-44958?
To fix CVE-2024-44958, update your Linux kernel to a version that includes the patch for this vulnerability.
Which versions of the Linux kernel are affected by CVE-2024-44958?
CVE-2024-44958 affects Linux kernel versions from 4.14.86 to 6.11-rc1, inclusive.
What issue does CVE-2024-44958 address in the Linux kernel?
CVE-2024-44958 addresses an unbalance issue in the sched_smt_present function leading to warning reports during stress tests.
What are the recommended Linux kernel versions to mitigate CVE-2024-44958?
Recommended Linux kernel versions to mitigate CVE-2024-44958 include 6.1.128-1, 6.12.12-1, or newer versions.