CVE-2025-38711: smb/server: avoid deadlock when linking with ReplaceIfExists
In the Linux kernel, the following vulnerability has been resolved:
smb/server: avoid deadlock when linking with ReplaceIfExists
If smb2createlink() is called with ReplaceIfExists set and the name does exist then a deadlock will happen.
ksmbdvfskernpathlocked() will return with success and the parent directory will be locked. ksmbdvfsremovefile() will then remove the file. ksmbdvfslink() will then be called while the parent is still locked. It will try to lock the same parent and will deadlock.
This patch moves the ksmbdvfskernpathunlock() call to before ksmbdvfslink() and then simplifies the code, removing the filepresent flag variable.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.113-1Fixed in 7.2.12-1Fixed in 7.2.13-1
Event History
Frequently Asked Questions
What is the severity of CVE-2025-38711?
CVE-2025-38711 is considered a moderate severity vulnerability due to the potential for deadlock situations in the Linux kernel.
How do I fix CVE-2025-38711?
To fix CVE-2025-38711, update the Linux kernel to the latest stable version that contains the patch for this vulnerability.
What does CVE-2025-38711 affect?
CVE-2025-38711 affects the Linux kernel's SMB server functionality, specifically during operations involving link creation with ReplaceIfExists.
What kind of attack could exploit CVE-2025-38711?
CVE-2025-38711 could potentially be exploited to cause denial of service through deadlock conditions during file link operations.
When was CVE-2025-38711 discovered?
CVE-2025-38711 was disclosed as a vulnerability in the Linux kernel related to SMB server operations.