[CIFS] acl support part 6

Acked-by: Shirish Pargaonkar <shirishp@us.ibm.com>
CC: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 40 insertions, 15 deletions

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 61d24f6ee64e..cc17e98991f3 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -2526,12 +2526,15 @@ smb_init_ntransact(const __u16 sub_command, const int setup_count,
 
 static int
 validate_ntransact(char *buf, char **ppparm, char **ppdata,
-                   int *pdatalen, int *pparmlen)
+                   __u32 *pdatalen, __u32 *pparmlen)
 {
         char *end_of_smb;
         __u32 data_count, data_offset, parm_count, parm_offset;
         struct smb_com_ntransact_rsp *pSMBr;
 
+        *pdatalen = 0;
+        *pparmlen = 0;
+
         if (buf == NULL)
                 return -EINVAL;
 
@@ -2568,6 +2571,8 @@ validate_ntransact(char *buf, char **ppparm, char **ppdata,
                 cFYI(1, ("parm count and data count larger than SMB"));
                 return -EINVAL;
         }
+        *pdatalen = data_count;
+        *pparmlen = parm_count;
         return 0;
 }
 #endif /* CIFS_EXPERIMENTAL */
@@ -3069,8 +3074,7 @@ GetExtAttrOut:
 /* Get Security Descriptor (by handle) from remote server for a file or dir */
 int
 CIFSSMBGetCIFSACL(const int xid, struct cifsTconInfo *tcon, __u16 fid,
-                /* BB fix up return info */ char *acl_inf, const int buflen,
-                  const int acl_type)
+                  struct cifs_ntsd **acl_inf, __u32 *pbuflen)
 {
         int rc = 0;
         int buf_type = 0;
@@ -3079,6 +3083,9 @@ CIFSSMBGetCIFSACL(const int xid, struct cifsTconInfo *tcon, __u16 fid,
 
         cFYI(1, ("GetCifsACL"));
 
+        *pbuflen = 0;
+        *acl_inf = NULL;
+
         rc = smb_init_ntransact(NT_TRANSACT_QUERY_SECURITY_DESC, 0,
                         8 /* parm len */, tcon, (void **) &pSMB);
         if (rc)
@@ -3101,34 +3108,52 @@ CIFSSMBGetCIFSACL(const int xid, struct cifsTconInfo *tcon, __u16 fid,
         if (rc) {
                 cFYI(1, ("Send error in QuerySecDesc = %d", rc));
         } else {                /* decode response */
-                struct cifs_ntsd *psec_desc;
                 __le32 * parm;
-                int parm_len;
-                int data_len;
-                int acl_len;
+                __u32 parm_len;
+                __u32 acl_len;
                 struct smb_com_ntransact_rsp *pSMBr;
+                char *pdata;
 
 /* validate_nttransact */
                 rc = validate_ntransact(iov[0].iov_base, (char **)&parm,
-                                        (char **)&psec_desc,
-                                        &parm_len, &data_len);
+                                        &pdata, &parm_len, pbuflen);
                 if (rc)
                         goto qsec_out;
                 pSMBr = (struct smb_com_ntransact_rsp *)iov[0].iov_base;
 
-                cFYI(1, ("smb %p parm %p data %p", pSMBr, parm, psec_desc));
+                cFYI(1, ("smb %p parm %p data %p", pSMBr, parm, *acl_inf));
 
                 if (le32_to_cpu(pSMBr->ParameterCount) != 4) {
                         rc = -EIO;      /* bad smb */
+                        *pbuflen = 0;
                         goto qsec_out;
                 }
 
 /* BB check that data area is minimum length and as big as acl_len */
 
                 acl_len = le32_to_cpu(*parm);
-                /* BB check if (acl_len > bufsize) */
+                if (acl_len != *pbuflen) {
+                        cERROR(1, ("acl length %d does not match %d",
+                                   acl_len, *pbuflen));
+                        if (*pbuflen > acl_len)
+                                *pbuflen = acl_len;
+                }
 
-                parse_sec_desc(psec_desc, acl_len);
+                /* check if buffer is big enough for the acl
+                   header followed by the smallest SID */
+                if ((*pbuflen < sizeof(struct cifs_ntsd) + 8) ||
+                    (*pbuflen >= 64 * 1024)) {
+                        cERROR(1, ("bad acl length %d", *pbuflen));
+                        rc = -EINVAL;
+                        *pbuflen = 0;
+                } else {
+                        *acl_inf = kmalloc(*pbuflen, GFP_KERNEL);
+                        if (*acl_inf == NULL) {
+                                *pbuflen = 0;
+                                rc = -ENOMEM;
+                        }
+                        memcpy(*acl_inf, pdata, *pbuflen);
+                }
         }
 qsec_out:
         if (buf_type == CIFS_SMALL_BUFFER)
@@ -3383,7 +3408,7 @@ UnixQPathInfoRetry:
                         memcpy((char *) pFindData,
                                (char *) &pSMBr->hdr.Protocol +
                                data_offset,
-                               sizeof (FILE_UNIX_BASIC_INFO));
+                               sizeof(FILE_UNIX_BASIC_INFO));
                 }
         }
         cifs_buf_release(pSMB);
@@ -3651,7 +3676,7 @@ int CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
         pSMB->SubCommand = cpu_to_le16(TRANS2_FIND_NEXT);
         pSMB->SearchHandle = searchHandle;      /* always kept as le */
         pSMB->SearchCount =
-                cpu_to_le16(CIFSMaxBufSize / sizeof (FILE_UNIX_INFO));
+                cpu_to_le16(CIFSMaxBufSize / sizeof(FILE_UNIX_INFO));
         pSMB->InformationLevel = cpu_to_le16(psrch_inf->info_level);
         pSMB->ResumeKey = psrch_inf->resume_key;
         pSMB->SearchFlags =
@@ -4333,7 +4358,7 @@ QFSDeviceRetry:
         } else {                /* decode response */
                 rc = validate_t2((struct smb_t2_rsp *)pSMBr);
 
-                if (rc || (pSMBr->ByteCount < sizeof (FILE_SYSTEM_DEVICE_INFO)))
+                if (rc || (pSMBr->ByteCount < sizeof(FILE_SYSTEM_DEVICE_INFO)))
                         rc = -EIO;      /* bad smb */
                 else {
                         __u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);