4 files changed, 92 insertions, 71 deletions

diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
index 11ca24a8e054..948676db8e2e 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -1495,11 +1495,12 @@ struct reparse_data {
         __u32   ReparseTag;
         __u16   ReparseDataLength;
         __u16   Reserved;
-        __u16   AltNameOffset;
-        __u16   AltNameLen;
-        __u16   TargetNameOffset;
-        __u16   TargetNameLen;
-        char    LinkNamesBuf[1];
+        __u16   SubstituteNameOffset;
+        __u16   SubstituteNameLength;
+        __u16   PrintNameOffset;
+        __u16   PrintNameLength;
+        __u32   Flags;
+        char    PathBuffer[0];
 } __attribute__((packed));
 
 struct cifs_quota_data {
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index b29a012bed33..5b05eb082a41 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -357,13 +357,9 @@ extern int CIFSSMBUnixQuerySymLink(const unsigned int xid,
                         struct cifs_tcon *tcon,
                         const unsigned char *searchName, char **syminfo,
                         const struct nls_table *nls_codepage);
-#ifdef CONFIG_CIFS_SYMLINK_EXPERIMENTAL
-extern int CIFSSMBQueryReparseLinkInfo(const unsigned int xid,
-                        struct cifs_tcon *tcon,
-                        const unsigned char *searchName,
-                        char *symlinkinfo, const int buflen, __u16 fid,
-                        const struct nls_table *nls_codepage);
-#endif /* temporarily unused until cifs_symlink fixed */
+extern int CIFSSMBQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
+                               __u16 fid, char **symlinkinfo,
+                               const struct nls_table *nls_codepage);
 extern int CIFSSMBOpen(const unsigned int xid, struct cifs_tcon *tcon,
                         const char *fileName, const int disposition,
                         const int access_flags, const int omode,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index a89c4cb4e6cf..a3d74fea1623 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -3067,7 +3067,6 @@ querySymLinkRetry:
         return rc;
 }
 
-#ifdef CONFIG_CIFS_SYMLINK_EXPERIMENTAL
 /*
  *      Recent Windows versions now create symlinks more frequently
  *      and they use the "reparse point" mechanism below.  We can of course
@@ -3079,18 +3078,22 @@ querySymLinkRetry:
  *      it is not compiled in by default until callers fixed up and more tested.
  */
 int
-CIFSSMBQueryReparseLinkInfo(const unsigned int xid, struct cifs_tcon *tcon,
-                        const unsigned char *searchName,
-                        char *symlinkinfo, const int buflen, __u16 fid,
-                        const struct nls_table *nls_codepage)
+CIFSSMBQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
+                    __u16 fid, char **symlinkinfo,
+                    const struct nls_table *nls_codepage)
 {
         int rc = 0;
         int bytes_returned;
         struct smb_com_transaction_ioctl_req *pSMB;
         struct smb_com_transaction_ioctl_rsp *pSMBr;
+        bool is_unicode;
+        unsigned int sub_len;
+        char *sub_start;
+        struct reparse_data *reparse_buf;
+        __u32 data_offset, data_count;
+        char *end_of_smb;
 
-        cifs_dbg(FYI, "In Windows reparse style QueryLink for path %s\n",
-                 searchName);
+        cifs_dbg(FYI, "In Windows reparse style QueryLink for fid %u\n", fid);
         rc = smb_init(SMB_COM_NT_TRANSACT, 23, tcon, (void **) &pSMB,
                       (void **) &pSMBr);
         if (rc)
@@ -3119,66 +3122,55 @@ CIFSSMBQueryReparseLinkInfo(const unsigned int xid, struct cifs_tcon *tcon,
                          (struct smb_hdr *) pSMBr, &bytes_returned, 0);
         if (rc) {
                 cifs_dbg(FYI, "Send error in QueryReparseLinkInfo = %d\n", rc);
-        } else {                /* decode response */
-                __u32 data_offset = le32_to_cpu(pSMBr->DataOffset);
-                __u32 data_count = le32_to_cpu(pSMBr->DataCount);
-                if (get_bcc(&pSMBr->hdr) < 2 || data_offset > 512) {
-                        /* BB also check enough total bytes returned */
-                        rc = -EIO;      /* bad smb */
-                        goto qreparse_out;
-                }
-                if (data_count && (data_count < 2048)) {
-                        char *end_of_smb = 2 /* sizeof byte count */ +
-                               get_bcc(&pSMBr->hdr) + (char *)&pSMBr->ByteCount;
-
-                        struct reparse_data *reparse_buf =
-                                                (struct reparse_data *)
-                                                ((char *)&pSMBr->hdr.Protocol
-                                                                 + data_offset);
-                        if ((char *)reparse_buf >= end_of_smb) {
-                                rc = -EIO;
-                                goto qreparse_out;
-                        }
-                        if ((reparse_buf->LinkNamesBuf +
-                                reparse_buf->TargetNameOffset +
-                                reparse_buf->TargetNameLen) > end_of_smb) {
-                                cifs_dbg(FYI, "reparse buf beyond SMB\n");
-                                rc = -EIO;
-                                goto qreparse_out;
-                        }
+                goto qreparse_out;
+        }
 
-                        if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) {
-                                cifs_from_ucs2(symlinkinfo, (__le16 *)
-                                                (reparse_buf->LinkNamesBuf +
-                                                reparse_buf->TargetNameOffset),
-                                                buflen,
-                                                reparse_buf->TargetNameLen,
-                                                nls_codepage, 0);
-                        } else { /* ASCII names */
-                                strncpy(symlinkinfo,
-                                        reparse_buf->LinkNamesBuf +
-                                        reparse_buf->TargetNameOffset,
-                                        min_t(const int, buflen,
-                                           reparse_buf->TargetNameLen));
-                        }
-                } else {
-                        rc = -EIO;
-                        cifs_dbg(FYI, "Invalid return data count on get reparse info ioctl\n");
-                }
-                symlinkinfo[buflen] = 0; /* just in case so the caller
-                                        does not go off the end of the buffer */
-                cifs_dbg(FYI, "readlink result - %s\n", symlinkinfo);
+        data_offset = le32_to_cpu(pSMBr->DataOffset);
+        data_count = le32_to_cpu(pSMBr->DataCount);
+        if (get_bcc(&pSMBr->hdr) < 2 || data_offset > 512) {
+                /* BB also check enough total bytes returned */
+                rc = -EIO;      /* bad smb */
+                goto qreparse_out;
+        }
+        if (!data_count || (data_count > 2048)) {
+                rc = -EIO;
+                cifs_dbg(FYI, "Invalid return data count on get reparse info ioctl\n");
+                goto qreparse_out;
+        }
+        end_of_smb = 2 + get_bcc(&pSMBr->hdr) + (char *)&pSMBr->ByteCount;
+        reparse_buf = (struct reparse_data *)
+                                ((char *)&pSMBr->hdr.Protocol + data_offset);
+        if ((char *)reparse_buf >= end_of_smb) {
+                rc = -EIO;
+                goto qreparse_out;
         }
+        if ((reparse_buf->PathBuffer + reparse_buf->PrintNameOffset +
+                                reparse_buf->PrintNameLength) > end_of_smb) {
+                cifs_dbg(FYI, "reparse buf beyond SMB\n");
+                rc = -EIO;
+                goto qreparse_out;
+        }
+        sub_start = reparse_buf->SubstituteNameOffset + reparse_buf->PathBuffer;
+        sub_len = reparse_buf->SubstituteNameLength;
+        if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE)
+                is_unicode = true;
+        else
+                is_unicode = false;
 
+        /* BB FIXME investigate remapping reserved chars here */
+        *symlinkinfo = cifs_strndup_from_utf16(sub_start, sub_len, is_unicode,
+                                               nls_codepage);
+        if (!*symlinkinfo)
+                rc = -ENOMEM;
 qreparse_out:
         cifs_buf_release(pSMB);
 
-        /* Note: On -EAGAIN error only caller can retry on handle based calls
-                since file handle passed in no longer valid */
-
+        /*
+         * Note: On -EAGAIN error only caller can retry on handle based calls
+         * since file handle passed in no longer valid.
+         */
         return rc;
 }
-#endif /* CIFS_SYMLINK_EXPERIMENTAL */ /* BB temporarily unused */
 
 #ifdef CONFIG_CIFS_POSIX
 
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index 60943978aec3..8fe19c973ee4 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -881,6 +881,37 @@ cifs_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
                            (__u8)type, wait, 0);
 }
 
+static int
+cifs_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
+                   const char *full_path, char **target_path,
+                   struct cifs_sb_info *cifs_sb)
+{
+        int rc;
+        int oplock = 0;
+        __u16 netfid;
+
+        cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);
+
+        rc = CIFSSMBOpen(xid, tcon, full_path, FILE_OPEN,
+                         FILE_READ_ATTRIBUTES, OPEN_REPARSE_POINT, &netfid,
+                         &oplock, NULL, cifs_sb->local_nls,
+                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+        if (rc)
+                return rc;
+
+        rc = CIFSSMBQuerySymLink(xid, tcon, netfid, target_path,
+                                 cifs_sb->local_nls);
+        if (rc) {
+                CIFSSMBClose(xid, tcon, netfid);
+                return rc;
+        }
+
+        convert_delimiter(*target_path, '/');
+        CIFSSMBClose(xid, tcon, netfid);
+        cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);
+        return rc;
+}
+
 struct smb_version_operations smb1_operations = {
         .send_cancel = send_nt_cancel,
         .compare_fids = cifs_compare_fids,
@@ -927,6 +958,7 @@ struct smb_version_operations smb1_operations = {
         .rename_pending_delete = cifs_rename_pending_delete,
         .rename = CIFSSMBRename,
         .create_hardlink = CIFSCreateHardLink,
+        .query_symlink = cifs_query_symlink,
         .open = cifs_open_file,
         .set_fid = cifs_set_fid,
         .close = cifs_close_file,