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

smb: client: fix use-after-free of signing key

Customers have reported use-after-free in @ses->auth_key.response with
SMB2.1 + sign mounts which occurs due to following race:

task A task B
cifs_mount()
dfs_mount_share()
get_session()
cifs_mount_get_session() cifs_send_recv()
cifs_get_smb_ses() compound_send_recv()
cifs_setup_session() smb2_setup_request()
kfree_sensitive() smb2_calc_signature()
crypto_shash_setkey() UAF

Fix this by ensuring that we have a valid @ses->auth_key.response by
checking whether @ses->ses_status is SES_GOOD or SES_EXITING with
@ses->ses_lock held. After commit 24a9799aa8ef ("smb: client: fix UAF
in smb2_reconnect_server()"), we made sure to call ->logoff() only
when @SES was known to be good (e.g. valid ->auth_key.response), so
it's safe to access signing key when @ses->ses_status == SES_EXITING.

References

• https://nvd.nist.gov/vuln/detail/CVE-2024-53179
• https://git.kernel.org/stable/c/0e2b654a3848bf9da3b0d54c1ccf3f1b8c635591
• https://git.kernel.org/stable/c/343d7fe6df9e247671440a932b6a73af4fa86d95
• https://git.kernel.org/stable/c/39619c65ab4bbb3e78c818f537687653e112764d