1 files changed, 85 insertions, 49 deletions

diff --git a/fs/smb/client/cifsacl.c b/fs/smb/client/cifsacl.c
index 1d294d53f662..63b3b1290bed 100644
--- a/fs/smb/client/cifsacl.c
+++ b/fs/smb/client/cifsacl.c
@@ -763,7 +763,7 @@ static void parse_dacl(struct smb_acl *pdacl, char *end_of_acl,
 		       struct cifs_fattr *fattr, bool mode_from_special_sid)
 {
 	int i;
-	int num_aces = 0;
+	u16 num_aces = 0;
 	int acl_size;
 	char *acl_base;
 	struct smb_ace **ppace;
@@ -778,14 +778,15 @@ static void parse_dacl(struct smb_acl *pdacl, char *end_of_acl,
 	}
 
 	/* validate that we do not go past end of acl */
-	if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
+	if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
+	    end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
 		cifs_dbg(VFS, "ACL too small to parse DACL\n");
 		return;
 	}
 
 	cifs_dbg(NOISY, "DACL revision %d size %d num aces %d\n",
 		 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
-		 le32_to_cpu(pdacl->num_aces));
+		 le16_to_cpu(pdacl->num_aces));
 
 	/* reset rwx permissions for user/group/other.
 	   Also, if num_aces is 0 i.e. DACL has no ACEs,
@@ -795,19 +796,38 @@ static void parse_dacl(struct smb_acl *pdacl, char *end_of_acl,
 	acl_base = (char *)pdacl;
 	acl_size = sizeof(struct smb_acl);
 
-	num_aces = le32_to_cpu(pdacl->num_aces);
+	num_aces = le16_to_cpu(pdacl->num_aces);
 	if (num_aces > 0) {
 		umode_t denied_mode = 0;
 
-		if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
+		if (num_aces > (le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) /
+				(offsetof(struct smb_ace, sid) +
+				 offsetof(struct smb_sid, sub_auth) + sizeof(__le16)))
 			return;
+
 		ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *),
 				      GFP_KERNEL);
 		if (!ppace)
 			return;
 
 		for (i = 0; i < num_aces; ++i) {
+			if (end_of_acl - acl_base < acl_size)
+				break;
+
 			ppace[i] = (struct smb_ace *) (acl_base + acl_size);
+			acl_base = (char *)ppace[i];
+			acl_size = offsetof(struct smb_ace, sid) +
+				offsetof(struct smb_sid, sub_auth);
+
+			if (end_of_acl - acl_base < acl_size ||
+			    ppace[i]->sid.num_subauth == 0 ||
+			    ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
+			    (end_of_acl - acl_base <
+			     acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
+			    (le16_to_cpu(ppace[i]->size) <
+			     acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
+				break;
+
 #ifdef CONFIG_CIFS_DEBUG2
 			dump_ace(ppace[i], end_of_acl);
 #endif
@@ -851,7 +871,6 @@ static void parse_dacl(struct smb_acl *pdacl, char *end_of_acl,
 				(void *)ppace[i],
 				sizeof(struct smb_ace)); */
 
-			acl_base = (char *)ppace[i];
 			acl_size = le16_to_cpu(ppace[i]->size);
 		}
 
@@ -885,12 +904,17 @@ unsigned int setup_authusers_ACE(struct smb_ace *pntace)
  * Fill in the special SID based on the mode. See
  * https://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
  */
-unsigned int setup_special_mode_ACE(struct smb_ace *pntace, __u64 nmode)
+unsigned int setup_special_mode_ACE(struct smb_ace *pntace,
+				    bool posix,
+				    __u64 nmode)
 {
 	int i;
 	unsigned int ace_size = 28;
 
-	pntace->type = ACCESS_DENIED_ACE_TYPE;
+	if (posix)
+		pntace->type = ACCESS_ALLOWED_ACE_TYPE;
+	else
+		pntace->type = ACCESS_DENIED_ACE_TYPE;
 	pntace->flags = 0x0;
 	pntace->access_req = 0;
 	pntace->sid.num_subauth = 3;
@@ -932,11 +956,12 @@ unsigned int setup_special_user_owner_ACE(struct smb_ace *pntace)
 static void populate_new_aces(char *nacl_base,
 		struct smb_sid *pownersid,
 		struct smb_sid *pgrpsid,
-		__u64 *pnmode, u32 *pnum_aces, u16 *pnsize,
-		bool modefromsid)
+		__u64 *pnmode, u16 *pnum_aces, u16 *pnsize,
+		bool modefromsid,
+		bool posix)
 {
 	__u64 nmode;
-	u32 num_aces = 0;
+	u16 num_aces = 0;
 	u16 nsize = 0;
 	__u64 user_mode;
 	__u64 group_mode;
@@ -950,13 +975,15 @@ static void populate_new_aces(char *nacl_base,
 	num_aces = *pnum_aces;
 	nsize = *pnsize;
 
-	if (modefromsid) {
+	if (modefromsid || posix) {
 		pnntace = (struct smb_ace *) (nacl_base + nsize);
-		nsize += setup_special_mode_ACE(pnntace, nmode);
-		num_aces++;
-		pnntace = (struct smb_ace *) (nacl_base + nsize);
-		nsize += setup_authusers_ACE(pnntace);
+		nsize += setup_special_mode_ACE(pnntace, posix, nmode);
 		num_aces++;
+		if (modefromsid) {
+			pnntace = (struct smb_ace *) (nacl_base + nsize);
+			nsize += setup_authusers_ACE(pnntace);
+			num_aces++;
+		}
 		goto set_size;
 	}
 
@@ -1042,7 +1069,7 @@ static __u16 replace_sids_and_copy_aces(struct smb_acl *pdacl, struct smb_acl *p
 	u16 size = 0;
 	struct smb_ace *pntace = NULL;
 	char *acl_base = NULL;
-	u32 src_num_aces = 0;
+	u16 src_num_aces = 0;
 	u16 nsize = 0;
 	struct smb_ace *pnntace = NULL;
 	char *nacl_base = NULL;
@@ -1050,7 +1077,7 @@ static __u16 replace_sids_and_copy_aces(struct smb_acl *pdacl, struct smb_acl *p
 
 	acl_base = (char *)pdacl;
 	size = sizeof(struct smb_acl);
-	src_num_aces = le32_to_cpu(pdacl->num_aces);
+	src_num_aces = le16_to_cpu(pdacl->num_aces);
 
 	nacl_base = (char *)pndacl;
 	nsize = sizeof(struct smb_acl);
@@ -1076,17 +1103,17 @@ static __u16 replace_sids_and_copy_aces(struct smb_acl *pdacl, struct smb_acl *p
 
 static int set_chmod_dacl(struct smb_acl *pdacl, struct smb_acl *pndacl,
 		struct smb_sid *pownersid,	struct smb_sid *pgrpsid,
-		__u64 *pnmode, bool mode_from_sid)
+		__u64 *pnmode, bool mode_from_sid, bool posix)
 {
 	int i;
 	u16 size = 0;
 	struct smb_ace *pntace = NULL;
 	char *acl_base = NULL;
-	u32 src_num_aces = 0;
+	u16 src_num_aces = 0;
 	u16 nsize = 0;
 	struct smb_ace *pnntace = NULL;
 	char *nacl_base = NULL;
-	u32 num_aces = 0;
+	u16 num_aces = 0;
 	bool new_aces_set = false;
 
 	/* Assuming that pndacl and pnmode are never NULL */
@@ -1094,17 +1121,17 @@ static int set_chmod_dacl(struct smb_acl *pdacl, struct smb_acl *pndacl,
 	nsize = sizeof(struct smb_acl);
 
 	/* If pdacl is NULL, we don't have a src. Simply populate new ACL. */
-	if (!pdacl) {
+	if (!pdacl || posix) {
 		populate_new_aces(nacl_base,
 				pownersid, pgrpsid,
 				pnmode, &num_aces, &nsize,
-				mode_from_sid);
+				mode_from_sid, posix);
 		goto finalize_dacl;
 	}
 
 	acl_base = (char *)pdacl;
 	size = sizeof(struct smb_acl);
-	src_num_aces = le32_to_cpu(pdacl->num_aces);
+	src_num_aces = le16_to_cpu(pdacl->num_aces);
 
 	/* Retain old ACEs which we can retain */
 	for (i = 0; i < src_num_aces; ++i) {
@@ -1115,7 +1142,7 @@ static int set_chmod_dacl(struct smb_acl *pdacl, struct smb_acl *pndacl,
 			populate_new_aces(nacl_base,
 					pownersid, pgrpsid,
 					pnmode, &num_aces, &nsize,
-					mode_from_sid);
+					mode_from_sid, posix);
 
 			new_aces_set = true;
 		}
@@ -1144,13 +1171,13 @@ next_ace:
 		populate_new_aces(nacl_base,
 				pownersid, pgrpsid,
 				pnmode, &num_aces, &nsize,
-				mode_from_sid);
+				mode_from_sid, posix);
 
 		new_aces_set = true;
 	}
 
 finalize_dacl:
-	pndacl->num_aces = cpu_to_le32(num_aces);
+	pndacl->num_aces = cpu_to_le16(num_aces);
 	pndacl->size = cpu_to_le16(nsize);
 
 	return 0;
@@ -1251,7 +1278,7 @@ static int parse_sec_desc(struct cifs_sb_info *cifs_sb,
 /* Convert permission bits from mode to equivalent CIFS ACL */
 static int build_sec_desc(struct smb_ntsd *pntsd, struct smb_ntsd *pnntsd,
 	__u32 secdesclen, __u32 *pnsecdesclen, __u64 *pnmode, kuid_t uid, kgid_t gid,
-	bool mode_from_sid, bool id_from_sid, int *aclflag)
+	bool mode_from_sid, bool id_from_sid, bool posix, int *aclflag)
 {
 	int rc = 0;
 	__u32 dacloffset;
@@ -1285,10 +1312,10 @@ static int build_sec_desc(struct smb_ntsd *pntsd, struct smb_ntsd *pnntsd,
 			dacloffset ? dacl_ptr->revision : cpu_to_le16(ACL_REVISION);
 
 		ndacl_ptr->size = cpu_to_le16(0);
-		ndacl_ptr->num_aces = cpu_to_le32(0);
+		ndacl_ptr->num_aces = cpu_to_le16(0);
 
 		rc = set_chmod_dacl(dacl_ptr, ndacl_ptr, owner_sid_ptr, group_sid_ptr,
-				    pnmode, mode_from_sid);
+				    pnmode, mode_from_sid, posix);
 
 		sidsoffset = ndacloffset + le16_to_cpu(ndacl_ptr->size);
 		/* copy the non-dacl portion of secdesc */
@@ -1387,7 +1414,7 @@ chown_chgrp_exit:
 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 struct smb_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb,
 				      const struct cifs_fid *cifsfid, u32 *pacllen,
-				      u32 __maybe_unused unused)
+				      u32 info)
 {
 	struct smb_ntsd *pntsd = NULL;
 	unsigned int xid;
@@ -1399,7 +1426,7 @@ struct smb_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb,
 
 	xid = get_xid();
 	rc = CIFSSMBGetCIFSACL(xid, tlink_tcon(tlink), cifsfid->netfid, &pntsd,
-				pacllen);
+				pacllen, info);
 	free_xid(xid);
 
 	cifs_put_tlink(tlink);
@@ -1411,7 +1438,7 @@ struct smb_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb,
 }
 
 static struct smb_ntsd *get_cifs_acl_by_path(struct cifs_sb_info *cifs_sb,
-		const char *path, u32 *pacllen)
+		const char *path, u32 *pacllen, u32 info)
 {
 	struct smb_ntsd *pntsd = NULL;
 	int oplock = 0;
@@ -1438,9 +1465,12 @@ static struct smb_ntsd *get_cifs_acl_by_path(struct cifs_sb_info *cifs_sb,
 		.fid = &fid,
 	};
 
+	if (info & SACL_SECINFO)
+		oparms.desired_access |= SYSTEM_SECURITY;
+
 	rc = CIFS_open(xid, &oparms, &oplock, NULL);
 	if (!rc) {
-		rc = CIFSSMBGetCIFSACL(xid, tcon, fid.netfid, &pntsd, pacllen);
+		rc = CIFSSMBGetCIFSACL(xid, tcon, fid.netfid, &pntsd, pacllen, info);
 		CIFSSMBClose(xid, tcon, fid.netfid);
 	}
 
@@ -1464,7 +1494,7 @@ struct smb_ntsd *get_cifs_acl(struct cifs_sb_info *cifs_sb,
 	if (inode)
 		open_file = find_readable_file(CIFS_I(inode), true);
 	if (!open_file)
-		return get_cifs_acl_by_path(cifs_sb, path, pacllen);
+		return get_cifs_acl_by_path(cifs_sb, path, pacllen, info);
 
 	pntsd = get_cifs_acl_by_fid(cifs_sb, &open_file->fid, pacllen, info);
 	cifsFileInfo_put(open_file);
@@ -1477,7 +1507,7 @@ int set_cifs_acl(struct smb_ntsd *pnntsd, __u32 acllen,
 {
 	int oplock = 0;
 	unsigned int xid;
-	int rc, access_flags;
+	int rc, access_flags = 0;
 	struct cifs_tcon *tcon;
 	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 	struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
@@ -1490,10 +1520,12 @@ int set_cifs_acl(struct smb_ntsd *pnntsd, __u32 acllen,
 	tcon = tlink_tcon(tlink);
 	xid = get_xid();
 
-	if (aclflag == CIFS_ACL_OWNER || aclflag == CIFS_ACL_GROUP)
-		access_flags = WRITE_OWNER;
-	else
-		access_flags = WRITE_DAC;
+	if (aclflag & CIFS_ACL_OWNER || aclflag & CIFS_ACL_GROUP)
+		access_flags |= WRITE_OWNER;
+	if (aclflag & CIFS_ACL_SACL)
+		access_flags |= SYSTEM_SECURITY;
+	if (aclflag & CIFS_ACL_DACL)
+		access_flags |= WRITE_DAC;
 
 	oparms = (struct cifs_open_parms) {
 		.tcon = tcon,
@@ -1533,7 +1565,7 @@ cifs_acl_to_fattr(struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
 	int rc = 0;
 	struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
 	struct smb_version_operations *ops;
-	const u32 info = 0;
+	const u32 info = OWNER_SECINFO | GROUP_SECINFO | DACL_SECINFO;
 
 	cifs_dbg(NOISY, "converting ACL to mode for %s\n", path);
 
@@ -1584,13 +1616,16 @@ id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 *pnmode,
 	struct smb_ntsd *pntsd = NULL; /* acl obtained from server */
 	struct smb_ntsd *pnntsd = NULL; /* modified acl to be sent to server */
 	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
-	struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
+	struct tcon_link *tlink;
 	struct smb_version_operations *ops;
 	bool mode_from_sid, id_from_sid;
-	const u32 info = 0;
+	const u32 info = OWNER_SECINFO | GROUP_SECINFO | DACL_SECINFO;
+	bool posix;
 
+	tlink = cifs_sb_tlink(cifs_sb);
 	if (IS_ERR(tlink))
 		return PTR_ERR(tlink);
+	posix = tlink_tcon(tlink)->posix_extensions;
 
 	ops = tlink_tcon(tlink)->ses->server->ops;
 
@@ -1622,12 +1657,13 @@ id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 *pnmode,
 		id_from_sid = false;
 
 	/* Potentially, five new ACEs can be added to the ACL for U,G,O mapping */
-	nsecdesclen = secdesclen;
 	if (pnmode && *pnmode != NO_CHANGE_64) { /* chmod */
-		if (mode_from_sid)
-			nsecdesclen += 2 * sizeof(struct smb_ace);
+		if (posix)
+			nsecdesclen = 1 * sizeof(struct smb_ace);
+		else if (mode_from_sid)
+			nsecdesclen = secdesclen + (2 * sizeof(struct smb_ace));
 		else /* cifsacl */
-			nsecdesclen += 5 * sizeof(struct smb_ace);
+			nsecdesclen = secdesclen + (5 * sizeof(struct smb_ace));
 	} else { /* chown */
 		/* When ownership changes, changes new owner sid length could be different */
 		nsecdesclen = sizeof(struct smb_ntsd) + (sizeof(struct smb_sid) * 2);
@@ -1636,7 +1672,7 @@ id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 *pnmode,
 			dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
 			if (mode_from_sid)
 				nsecdesclen +=
-					le32_to_cpu(dacl_ptr->num_aces) * sizeof(struct smb_ace);
+					le16_to_cpu(dacl_ptr->num_aces) * sizeof(struct smb_ace);
 			else /* cifsacl */
 				nsecdesclen += le16_to_cpu(dacl_ptr->size);
 		}
@@ -1657,7 +1693,7 @@ id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 *pnmode,
 	}
 
 	rc = build_sec_desc(pntsd, pnntsd, secdesclen, &nsecdesclen, pnmode, uid, gid,
-			    mode_from_sid, id_from_sid, &aclflag);
+			    mode_from_sid, id_from_sid, posix, &aclflag);
 
 	cifs_dbg(NOISY, "build_sec_desc rc: %d\n", rc);