kernel/linux.git/fs/smb/server/auth.c, branch v6.18.22

ksmbd: Don't log keys in SMB3 signing and encryption key generation

2026-03-25T10:10:33+00:00

[ Upstream commit 441336115df26b966575de56daf7107ed474faed ] When KSMBD_DEBUG_AUTH logging is enabled, generate_smb3signingkey() and generate_smb3encryptionkey() log the session, signing, encryption, and decryption key bytes. Remove the logs to avoid exposing credentials. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Cc: stable@vger.kernel.org Signed-off-by: Thorsten Blum Acked-by: Namjae Jeon Signed-off-by: Steve French [ Context ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ksmbd: Compare MACs in constant time

2026-03-19T15:08:50+00:00

commit c5794709bc9105935dbedef8b9cf9c06f2b559fa upstream. To prevent timing attacks, MAC comparisons need to be constant-time. Replace the memcmp() with the correct function, crypto_memneq(). Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

smb: Use arc4 library instead of duplicate arc4 code

2025-09-30T02:21:23+00:00

fs/smb/common/cifs_arc4.c has an implementation of ARC4, but a copy of this same code is also present in lib/crypto/arc4.c to serve the other users of this legacy algorithm in the kernel. Remove the duplicate implementation in fs/smb/, which seems to have been added because of a misunderstanding, and just use the lib/crypto/ one. Signed-off-by: Eric Biggers Reviewed-by: Paulo Alcantara (Red Hat) Signed-off-by: Steve French

ksmbd: use SHA-256 library API instead of crypto_shash API

2025-05-26T03:54:50+00:00

ksmbd_gen_sd_hash() does not support any other algorithm, so the crypto_shash abstraction provides no value. Just use the SHA-256 library API instead, which is much simpler and easier to use. Signed-off-by: Eric Biggers Acked-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: fix use-after-free in kerberos authentication

2025-04-25T23:22:01+00:00

Setting sess->user = NULL was introduced to fix the dangling pointer created by ksmbd_free_user. However, it is possible another thread could be operating on the session and make use of sess->user after it has been passed to ksmbd_free_user but before sess->user is set to NULL. Cc: stable@vger.kernel.org Signed-off-by: Sean Heelan Acked-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: fix session use-after-free in multichannel connection

2025-04-01T05:04:21+00:00

There is a race condition between session setup and ksmbd_sessions_deregister. The session can be freed before the connection is added to channel list of session. This patch check reference count of session before freeing it. Cc: stable@vger.kernel.org Reported-by: Sean Heelan Signed-off-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: use aead_request_free to match aead_request_alloc

2025-03-28T00:12:00+00:00

Use aead_request_free() instead of kfree() to properly free memory allocated by aead_request_alloc(). This ensures sensitive crypto data is zeroed before being freed. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Signed-off-by: Miaoqian Lin Acked-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: fix racy issue from session lookup and expire

2024-12-10T23:48:06+00:00

Increment the session reference count within the lock for lookup to avoid racy issue with session expire. Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-25737 Signed-off-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: use __GFP_RETRY_MAYFAIL

2024-11-26T00:58:02+00:00

Prefer to report ENOMEM rather than incur the oom for allocations in ksmbd. __GFP_NORETRY could not achieve that, It would fail the allocations just too easily. __GFP_RETRY_MAYFAIL will keep retrying the allocation until there is no more progress and fail the allocation instead go OOM and let the caller to deal with it. Signed-off-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: add support for supplementary groups

2024-10-11T16:02:14+00:00

Even though system user has a supplementary group, It gets NT_STATUS_ACCESS_DENIED when attempting to create file or directory. This patch add KSMBD_EVENT_LOGIN_REQUEST_EXT/RESPONSE_EXT netlink events to get supplementary groups list. The new netlink event doesn't break backward compatibility when using old ksmbd-tools. Co-developed-by: Atte Heikkilä Signed-off-by: Atte Heikkilä Signed-off-by: Namjae Jeon Signed-off-by: Steve French