From: Namjae Jeon linkinjeon@kernel.org
mainline inclusion from mainline-5.15-rc4 commit 442ff9ebeb0129e90483356f3d79c732e632a7a6 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I60T7G CVE: NA
Reference: https://git.kernel.org/torvalds/linux/c/442ff9ebeb01
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This patch add validation to check request buffer check in smb2 negotiate and fix null pointer deferencing oops in smb3_preauth_hash_rsp() that found from manual test.
Cc: Tom Talpey tom@talpey.com Cc: Ronnie Sahlberg ronniesahlberg@gmail.com Cc: Ralph Böhme slow@samba.org Cc: Hyunchul Lee hyc.lee@gmail.com Cc: Sergey Senozhatsky senozhatsky@chromium.org Reviewed-by: Ralph Boehme slow@samba.org Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zhong Jinghua zhongjinghua@huawei.com --- fs/ksmbd/smb2pdu.c | 42 +++++++++++++++++++++++++++++++++++++++++- fs/ksmbd/smb_common.c | 32 +++++++++++++++++++++++++++----- 2 files changed, 68 insertions(+), 6 deletions(-)
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 7ce7fa898a42..00dcd10a9d69 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1067,6 +1067,7 @@ int smb2_handle_negotiate(struct ksmbd_work *work) struct smb2_negotiate_req *req = work->request_buf; struct smb2_negotiate_rsp *rsp = work->response_buf; int rc = 0; + unsigned int smb2_buf_len, smb2_neg_size; __le32 status;
ksmbd_debug(SMB, "Received negotiate request\n"); @@ -1084,6 +1085,44 @@ int smb2_handle_negotiate(struct ksmbd_work *work) goto err_out; }
+ smb2_buf_len = get_rfc1002_len(work->request_buf); + smb2_neg_size = offsetof(struct smb2_negotiate_req, Dialects) - 4; + if (smb2_neg_size > smb2_buf_len) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + + if (conn->dialect == SMB311_PROT_ID) { + unsigned int nego_ctxt_off = le32_to_cpu(req->NegotiateContextOffset); + + if (smb2_buf_len < nego_ctxt_off) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + + if (smb2_neg_size > nego_ctxt_off) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + + if (smb2_neg_size + le16_to_cpu(req->DialectCount) * sizeof(__le16) > + nego_ctxt_off) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + } else { + if (smb2_neg_size + le16_to_cpu(req->DialectCount) * sizeof(__le16) > + smb2_buf_len) { + rsp->hdr.Status = STATUS_INVALID_PARAMETER; + rc = -EINVAL; + goto err_out; + } + } + conn->cli_cap = le32_to_cpu(req->Capabilities); switch (conn->dialect) { case SMB311_PROT_ID: @@ -8190,7 +8229,8 @@ void smb3_preauth_hash_rsp(struct ksmbd_work *work)
WORK_BUFFERS(work, req, rsp);
- if (le16_to_cpu(req->Command) == SMB2_NEGOTIATE_HE) + if (le16_to_cpu(req->Command) == SMB2_NEGOTIATE_HE && + conn->preauth_info) ksmbd_gen_preauth_integrity_hash(conn, (char *)rsp, conn->preauth_info->Preauth_HashValue);
diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c index 98c22a3abf92..02f17d5b8656 100644 --- a/fs/ksmbd/smb_common.c +++ b/fs/ksmbd/smb_common.c @@ -169,10 +169,12 @@ static bool supported_protocol(int idx) idx <= server_conf.max_protocol); }
-static char *next_dialect(char *dialect, int *next_off) +static char *next_dialect(char *dialect, int *next_off, int bcount) { dialect = dialect + *next_off; - *next_off = strlen(dialect); + *next_off = strnlen(dialect, bcount); + if (dialect[*next_off] != '\0') + return NULL; return dialect; }
@@ -187,7 +189,9 @@ static int ksmbd_lookup_dialect_by_name(char *cli_dialects, __le16 byte_count) dialect = cli_dialects; bcount = le16_to_cpu(byte_count); do { - dialect = next_dialect(dialect, &next); + dialect = next_dialect(dialect, &next, bcount); + if (!dialect) + break; ksmbd_debug(SMB, "client requested dialect %s\n", dialect); if (!strcmp(dialect, smb1_protos[i].name)) { @@ -235,13 +239,22 @@ int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count)
static int ksmbd_negotiate_smb_dialect(void *buf) { - __le32 proto; + int smb_buf_length = get_rfc1002_len(buf); + __le32 proto = ((struct smb2_hdr *)buf)->ProtocolId;
- proto = ((struct smb2_hdr *)buf)->ProtocolId; if (proto == SMB2_PROTO_NUMBER) { struct smb2_negotiate_req *req; + int smb2_neg_size = + offsetof(struct smb2_negotiate_req, Dialects) - 4;
req = (struct smb2_negotiate_req *)buf; + if (smb2_neg_size > smb_buf_length) + goto err_out; + + if (smb2_neg_size + le16_to_cpu(req->DialectCount) * sizeof(__le16) > + smb_buf_length) + goto err_out; + return ksmbd_lookup_dialect_by_id(req->Dialects, req->DialectCount); } @@ -251,10 +264,19 @@ static int ksmbd_negotiate_smb_dialect(void *buf) struct smb_negotiate_req *req;
req = (struct smb_negotiate_req *)buf; + if (le16_to_cpu(req->ByteCount) < 2) + goto err_out; + + if (offsetof(struct smb_negotiate_req, DialectsArray) - 4 + + le16_to_cpu(req->ByteCount) > smb_buf_length) { + goto err_out; + } + return ksmbd_lookup_dialect_by_name(req->DialectsArray, req->ByteCount); }
+err_out: return BAD_PROT_ID; }