The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 27893dfc1285f80f80f46b3b8c95f5d15d2e66d0 Mon Sep 17 00:00:00 2001 From: Enzo Matsumiya <ematsumiya@xxxxxxx> Date: Tue, 30 Aug 2022 19:51:51 -0300 Subject: [PATCH] cifs: fix small mempool leak in SMB2_negotiate() In some cases of failure (dialect mismatches) in SMB2_negotiate(), after the request is sent, the checks would return -EIO when they should be rather setting rc = -EIO and jumping to neg_exit to free the response buffer from mempool. Signed-off-by: Enzo Matsumiya <ematsumiya@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 128e44e57528..6352ab32c7e7 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -965,16 +965,17 @@ SMB2_negotiate(const unsigned int xid, } else if (rc != 0) goto neg_exit; + rc = -EIO; if (strcmp(server->vals->version_string, SMB3ANY_VERSION_STRING) == 0) { if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) { cifs_server_dbg(VFS, "SMB2 dialect returned but not requested\n"); - return -EIO; + goto neg_exit; } else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) { cifs_server_dbg(VFS, "SMB2.1 dialect returned but not requested\n"); - return -EIO; + goto neg_exit; } else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) { /* ops set to 3.0 by default for default so update */ server->ops = &smb311_operations; @@ -985,7 +986,7 @@ SMB2_negotiate(const unsigned int xid, if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) { cifs_server_dbg(VFS, "SMB2 dialect returned but not requested\n"); - return -EIO; + goto neg_exit; } else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) { /* ops set to 3.0 by default for default so update */ server->ops = &smb21_operations; @@ -999,7 +1000,7 @@ SMB2_negotiate(const unsigned int xid, /* if requested single dialect ensure returned dialect matched */ cifs_server_dbg(VFS, "Invalid 0x%x dialect returned: not requested\n", le16_to_cpu(rsp->DialectRevision)); - return -EIO; + goto neg_exit; } cifs_dbg(FYI, "mode 0x%x\n", rsp->SecurityMode); @@ -1017,9 +1018,10 @@ SMB2_negotiate(const unsigned int xid, else { cifs_server_dbg(VFS, "Invalid dialect returned by server 0x%x\n", le16_to_cpu(rsp->DialectRevision)); - rc = -EIO; goto neg_exit; } + + rc = 0; server->dialect = le16_to_cpu(rsp->DialectRevision); /*