CVE-2024-44992

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

smb/client: avoid possible NULL dereference in cifs_free_subrequest()

Clang static checker (scan-build) warning: cifsglob.h:line 890, column 3 Access to field ops results in a dereference of a null pointer.

Commit 519be989717c (cifs: Add a tracepoint to track credits involved in R/W requests) adds a check for rdata->server, and let clang throw this warning about NULL dereference.

When rdata->credits.value != 0 && rdata->server == NULL happens, add_credits_and_wake_if() will call rdata->server->ops->add_credits(). This will cause NULL dereference problem. Add a check for rdata->server to avoid NULL dereference.

Weakness

A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/74c2ab6d653b4c2354df65a7f7f2df1925a40a51
• https://git.kernel.org/stable/c/fead60a6d5f84b472b928502a42c419253afe6c1