1 files changed, 132 insertions, 74 deletions

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 1724066c1536..23f10e0d6e7e 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -2914,32 +2914,57 @@ CIFSSMB_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
 
 #ifdef CONFIG_CIFS_POSIX
 
-/*Convert an Access Control Entry from wire format to local POSIX xattr format*/
-static void cifs_convert_ace(struct posix_acl_xattr_entry *ace,
-			     struct cifs_posix_ace *cifs_ace)
+#ifdef CONFIG_FS_POSIX_ACL
+/**
+ * cifs_init_posix_acl - convert ACL from cifs to POSIX ACL format
+ * @ace: POSIX ACL entry to store converted ACL into
+ * @cifs_ace: ACL in cifs format
+ *
+ * Convert an Access Control Entry from wire format to local POSIX xattr
+ * format.
+ *
+ * Note that the @cifs_uid member is used to store both {g,u}id_t.
+ */
+static void cifs_init_posix_acl(struct posix_acl_entry *ace,
+				struct cifs_posix_ace *cifs_ace)
 {
 	/* u8 cifs fields do not need le conversion */
-	ace->e_perm = cpu_to_le16(cifs_ace->cifs_e_perm);
-	ace->e_tag  = cpu_to_le16(cifs_ace->cifs_e_tag);
-	ace->e_id   = cpu_to_le32(le64_to_cpu(cifs_ace->cifs_uid));
-/*
-	cifs_dbg(FYI, "perm %d tag %d id %d\n",
-		 ace->e_perm, ace->e_tag, ace->e_id);
-*/
+	ace->e_perm = cifs_ace->cifs_e_perm;
+	ace->e_tag = cifs_ace->cifs_e_tag;
 
+	switch (ace->e_tag) {
+	case ACL_USER:
+		ace->e_uid = make_kuid(&init_user_ns,
+				       le64_to_cpu(cifs_ace->cifs_uid));
+		break;
+	case ACL_GROUP:
+		ace->e_gid = make_kgid(&init_user_ns,
+				       le64_to_cpu(cifs_ace->cifs_uid));
+		break;
+	}
 	return;
 }
 
-/* Convert ACL from CIFS POSIX wire format to local Linux POSIX ACL xattr */
-static int cifs_copy_posix_acl(char *trgt, char *src, const int buflen,
-			       const int acl_type, const int size_of_data_area)
+/**
+ * cifs_to_posix_acl - copy cifs ACL format to POSIX ACL format
+ * @acl: ACLs returned in POSIX ACL format
+ * @src: ACLs in cifs format
+ * @acl_type: type of POSIX ACL requested
+ * @size_of_data_area: size of SMB we got
+ *
+ * This function converts ACLs from cifs format to POSIX ACL format.
+ * If @acl is NULL then the size of the buffer required to store POSIX ACLs in
+ * their uapi format is returned.
+ */
+static int cifs_to_posix_acl(struct posix_acl **acl, char *src,
+			     const int acl_type, const int size_of_data_area)
 {
 	int size =  0;
-	int i;
 	__u16 count;
 	struct cifs_posix_ace *pACE;
 	struct cifs_posix_acl *cifs_acl = (struct cifs_posix_acl *)src;
-	struct posix_acl_xattr_header *local_acl = (void *)trgt;
+	struct posix_acl *kacl = NULL;
+	struct posix_acl_entry *pa, *pe;
 
 	if (le16_to_cpu(cifs_acl->version) != CIFS_ACL_VERSION)
 		return -EOPNOTSUPP;
@@ -2959,7 +2984,7 @@ static int cifs_copy_posix_acl(char *trgt, char *src, const int buflen,
 		count = le16_to_cpu(cifs_acl->access_entry_count);
 		size = sizeof(struct cifs_posix_acl);
 		size += sizeof(struct cifs_posix_ace) * count;
-/* skip past access ACEs to get to default ACEs */
+		/* skip past access ACEs to get to default ACEs */
 		pACE = &cifs_acl->ace_array[count];
 		count = le16_to_cpu(cifs_acl->default_entry_count);
 		size += sizeof(struct cifs_posix_ace) * count;
@@ -2971,62 +2996,75 @@ static int cifs_copy_posix_acl(char *trgt, char *src, const int buflen,
 		return -EINVAL;
 	}
 
-	size = posix_acl_xattr_size(count);
-	if ((buflen == 0) || (local_acl == NULL)) {
-		/* used to query ACL EA size */
-	} else if (size > buflen) {
-		return -ERANGE;
-	} else /* buffer big enough */ {
-		struct posix_acl_xattr_entry *ace = (void *)(local_acl + 1);
-
-		local_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
-		for (i = 0; i < count ; i++) {
-			cifs_convert_ace(&ace[i], pACE);
-			pACE++;
-		}
+	/* Allocate number of POSIX ACLs to store in VFS format. */
+	kacl = posix_acl_alloc(count, GFP_NOFS);
+	if (!kacl)
+		return -ENOMEM;
+
+	FOREACH_ACL_ENTRY(pa, kacl, pe) {
+		cifs_init_posix_acl(pa, pACE);
+		pACE++;
 	}
-	return size;
+
+	*acl = kacl;
+	return 0;
 }
 
-static void convert_ace_to_cifs_ace(struct cifs_posix_ace *cifs_ace,
-				     const struct posix_acl_xattr_entry *local_ace)
+/**
+ * cifs_init_ace - convert ACL entry from POSIX ACL to cifs format
+ * @cifs_ace: the cifs ACL entry to store into
+ * @local_ace: the POSIX ACL entry to convert
+ */
+static void cifs_init_ace(struct cifs_posix_ace *cifs_ace,
+			  const struct posix_acl_entry *local_ace)
 {
-	cifs_ace->cifs_e_perm = le16_to_cpu(local_ace->e_perm);
-	cifs_ace->cifs_e_tag =  le16_to_cpu(local_ace->e_tag);
-	/* BB is there a better way to handle the large uid? */
-	if (local_ace->e_id == cpu_to_le32(-1)) {
-	/* Probably no need to le convert -1 on any arch but can not hurt */
+	cifs_ace->cifs_e_perm = local_ace->e_perm;
+	cifs_ace->cifs_e_tag =  local_ace->e_tag;
+
+	switch (local_ace->e_tag) {
+	case ACL_USER:
+		cifs_ace->cifs_uid =
+			cpu_to_le64(from_kuid(&init_user_ns, local_ace->e_uid));
+		break;
+	case ACL_GROUP:
+		cifs_ace->cifs_uid =
+			cpu_to_le64(from_kgid(&init_user_ns, local_ace->e_gid));
+		break;
+	default:
 		cifs_ace->cifs_uid = cpu_to_le64(-1);
-	} else
-		cifs_ace->cifs_uid = cpu_to_le64(le32_to_cpu(local_ace->e_id));
-/*
-	cifs_dbg(FYI, "perm %d tag %d id %d\n",
-		 ace->e_perm, ace->e_tag, ace->e_id);
-*/
+	}
 }
 
-/* Convert ACL from local Linux POSIX xattr to CIFS POSIX ACL wire format */
-static __u16 ACL_to_cifs_posix(char *parm_data, const char *pACL,
-			       const int buflen, const int acl_type)
+/**
+ * posix_acl_to_cifs - convert ACLs from POSIX ACL to cifs format
+ * @parm_data: ACLs in cifs format to conver to
+ * @acl: ACLs in POSIX ACL format to convert from
+ * @acl_type: the type of POSIX ACLs stored in @acl
+ *
+ * Return: the number cifs ACL entries after conversion
+ */
+static __u16 posix_acl_to_cifs(char *parm_data, const struct posix_acl *acl,
+			       const int acl_type)
 {
 	__u16 rc = 0;
 	struct cifs_posix_acl *cifs_acl = (struct cifs_posix_acl *)parm_data;
-	struct posix_acl_xattr_header *local_acl = (void *)pACL;
-	struct posix_acl_xattr_entry *ace = (void *)(local_acl + 1);
+	const struct posix_acl_entry *pa, *pe;
 	int count;
-	int i;
+	int i = 0;
 
-	if ((buflen == 0) || (pACL == NULL) || (cifs_acl == NULL))
+	if ((acl == NULL) || (cifs_acl == NULL))
 		return 0;
 
-	count = posix_acl_xattr_count((size_t)buflen);
-	cifs_dbg(FYI, "setting acl with %d entries from buf of length %d and version of %d\n",
-		 count, buflen, le32_to_cpu(local_acl->a_version));
-	if (le32_to_cpu(local_acl->a_version) != 2) {
-		cifs_dbg(FYI, "unknown POSIX ACL version %d\n",
-			 le32_to_cpu(local_acl->a_version));
-		return 0;
-	}
+	count = acl->a_count;
+	cifs_dbg(FYI, "setting acl with %d entries\n", count);
+
+	/*
+	 * Note that the uapi POSIX ACL version is verified by the VFS and is
+	 * independent of the cifs ACL version. Changing the POSIX ACL version
+	 * is a uapi change and if it's changed we will pass down the POSIX ACL
+	 * version in struct posix_acl from the VFS. For now there's really
+	 * only one that all filesystems know how to deal with.
+	 */
 	cifs_acl->version = cpu_to_le16(1);
 	if (acl_type == ACL_TYPE_ACCESS) {
 		cifs_acl->access_entry_count = cpu_to_le16(count);
@@ -3038,8 +3076,9 @@ static __u16 ACL_to_cifs_posix(char *parm_data, const char *pACL,
 		cifs_dbg(FYI, "unknown ACL type %d\n", acl_type);
 		return 0;
 	}
-	for (i = 0; i < count; i++)
-		convert_ace_to_cifs_ace(&cifs_acl->ace_array[i], &ace[i]);
+	FOREACH_ACL_ENTRY(pa, acl, pe) {
+		cifs_init_ace(&cifs_acl->ace_array[i++], pa);
+	}
 	if (rc == 0) {
 		rc = (__u16)(count * sizeof(struct cifs_posix_ace));
 		rc += sizeof(struct cifs_posix_acl);
@@ -3048,11 +3087,10 @@ static __u16 ACL_to_cifs_posix(char *parm_data, const char *pACL,
 	return rc;
 }
 
-int
-CIFSSMBGetPosixACL(const unsigned int xid, struct cifs_tcon *tcon,
-		   const unsigned char *searchName,
-		   char *acl_inf, const int buflen, const int acl_type,
-		   const struct nls_table *nls_codepage, int remap)
+int cifs_do_get_acl(const unsigned int xid, struct cifs_tcon *tcon,
+		    const unsigned char *searchName, struct posix_acl **acl,
+		    const int acl_type, const struct nls_table *nls_codepage,
+		    int remap)
 {
 /* SMB_QUERY_POSIX_ACL */
 	TRANSACTION2_QPI_REQ *pSMB = NULL;
@@ -3124,23 +3162,26 @@ queryAclRetry:
 		else {
 			__u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);
 			__u16 count = le16_to_cpu(pSMBr->t2.DataCount);
-			rc = cifs_copy_posix_acl(acl_inf,
+			rc = cifs_to_posix_acl(acl,
 				(char *)&pSMBr->hdr.Protocol+data_offset,
-				buflen, acl_type, count);
+				acl_type, count);
 		}
 	}
 	cifs_buf_release(pSMB);
+	/*
+	 * The else branch after SendReceive() doesn't return EAGAIN so if we
+	 * allocated @acl in cifs_to_posix_acl() we are guaranteed to return
+	 * here and don't leak POSIX ACLs.
+	 */
 	if (rc == -EAGAIN)
 		goto queryAclRetry;
 	return rc;
 }
 
-int
-CIFSSMBSetPosixACL(const unsigned int xid, struct cifs_tcon *tcon,
-		   const unsigned char *fileName,
-		   const char *local_acl, const int buflen,
-		   const int acl_type,
-		   const struct nls_table *nls_codepage, int remap)
+int cifs_do_set_acl(const unsigned int xid, struct cifs_tcon *tcon,
+		    const unsigned char *fileName, const struct posix_acl *acl,
+		    const int acl_type, const struct nls_table *nls_codepage,
+		    int remap)
 {
 	struct smb_com_transaction2_spi_req *pSMB = NULL;
 	struct smb_com_transaction2_spi_rsp *pSMBr = NULL;
@@ -3181,7 +3222,7 @@ setAclRetry:
 	pSMB->ParameterOffset = cpu_to_le16(param_offset);
 
 	/* convert to on the wire format for POSIX ACL */
-	data_count = ACL_to_cifs_posix(parm_data, local_acl, buflen, acl_type);
+	data_count = posix_acl_to_cifs(parm_data, acl, acl_type);
 
 	if (data_count == 0) {
 		rc = -EOPNOTSUPP;
@@ -3211,6 +3252,23 @@ setACLerrorExit:
 		goto setAclRetry;
 	return rc;
 }
+#else
+int cifs_do_get_acl(const unsigned int xid, struct cifs_tcon *tcon,
+		    const unsigned char *searchName, struct posix_acl **acl,
+		    const int acl_type, const struct nls_table *nls_codepage,
+		    int remap)
+{
+	return -EOPNOTSUPP;
+}
+
+int cifs_do_set_acl(const unsigned int xid, struct cifs_tcon *tcon,
+		    const unsigned char *fileName, const struct posix_acl *acl,
+		    const int acl_type, const struct nls_table *nls_codepage,
+		    int remap)
+{
+	return -EOPNOTSUPP;
+}
+#endif /* CONFIG_FS_POSIX_ACL */
 
 int
 CIFSGetExtAttr(const unsigned int xid, struct cifs_tcon *tcon,