kernel/linux.git/fs/smb/server/auth.c, branch v7.0.10

ksmbd: fix use-after-free from async crypto on Qualcomm crypto engine

2026-05-23T11:08:57+00:00

[ Upstream commit 3e298897f41c61450c2e7a4f457e8b2485eb35b3 ] ksmbd_crypt_message() sets a NULL completion callback on AEAD requests and does not handle the -EINPROGRESS return code from async hardware crypto engines like the Qualcomm Crypto Engine (QCE). When QCE returns -EINPROGRESS, ksmbd treats it as an error and immediately frees the request while the hardware DMA operation is still in flight. The DMA completion callback then dereferences freed memory, causing a NULL pointer crash: pc : qce_skcipher_done+0x24/0x174 lr : vchan_complete+0x230/0x27c ... el1h_64_irq+0x68/0x6c ksmbd_free_work_struct+0x20/0x118 [ksmbd] ksmbd_exit_file_cache+0x694/0xa4c [ksmbd] Use the standard crypto_wait_req() pattern with crypto_req_done() as the completion callback, matching the approach used by the SMB client in fs/smb/client/smb2ops.c. This properly handles both synchronous engines (immediate return) and async engines (-EINPROGRESS followed by callback notification). Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Link: https://github.com/openwrt/openwrt/issues/21822 Signed-off-by: Joshua Klinesmith Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin

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

2026-03-09T02:28:39+00:00

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

ksmbd: Compare MACs in constant time

2026-02-23T03:27:28+00:00

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

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

ksmbd: rename smb2_get_msg to smb_get_msg

2025-12-22T01:20:46+00:00

With the removal of the RFC1002 length field from the SMB header, smb2_get_msg is now used to get the smb1 request from the request buffer. Since this function is no longer exclusive to smb2 and now supports smb1 as well, This patch rename it to smb_get_msg to better reflect its usage. Signed-off-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: Use HMAC-MD5 library for NTLMv2

2025-12-01T03:11:43+00:00

For the HMAC-MD5 computations in NTLMv2, use the HMAC-MD5 library instead of a "hmac(md5)" crypto_shash. This is simpler and faster. With the library there's no need to allocate memory, no need to handle errors, and the HMAC-MD5 code is accessed directly without inefficient indirect calls and other unnecessary API overhead. To preserve the existing behavior of NTLMv2 support being disabled when the kernel is booted with "fips=1", make ksmbd_auth_ntlmv2() check fips_enabled itself. Previously it relied on the error from crypto_alloc_shash("hmac(md5)") being bubbled up. I don't know for sure that this is actually needed, but this preserves the existing behavior. Signed-off-by: Eric Biggers Acked-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: Use HMAC-SHA256 library for message signing and key generation

2025-12-01T03:11:43+00:00

Convert ksmbd_sign_smb2_pdu() and generate_key() to use the HMAC-SHA256 library instead of a "hmac(sha256)" crypto_shash. This is simpler and faster. With the library there's no need to allocate memory, no need to handle errors, and the HMAC-SHA256 code is accessed directly without inefficient indirect calls and other unnecessary API overhead. Signed-off-by: Eric Biggers Acked-by: Namjae Jeon Signed-off-by: Steve French

ksmbd: Use SHA-512 library for SMB3.1.1 preauth hash

2025-12-01T03:11:42+00:00

Convert ksmbd_gen_preauth_integrity_hash() to use the SHA-512 library instead of a "sha512" crypto_shash. This is simpler and faster. With the library there's no need to allocate memory, no need to handle errors, and the SHA-512 code is accessed directly without inefficient indirect calls and other unnecessary API overhead. Signed-off-by: Eric Biggers Acked-by: Namjae Jeon Signed-off-by: Steve French

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