diff mbox

Fix samba bug #8914

Message ID E1VjSnS-004B9V-Fo@intern.SerNet.DE (mailing list archive)
State New, archived
Headers show

Commit Message

Gregor Beck Nov. 21, 2013, 11:51 a.m. UTC 
Hi, 

NetApp sends brocken packages in response to trans2_query_path_info with info 
level smb_file_all_info as reported at: 
https://bugzilla.samba.org/show_bug.cgi?id=8914

The attached patch for cifs 2.01 works around the problem by retrying the 
operation with info levels basic and standard which yield the same 
information. 

Thanks
Gregor

Comments

Jeff Layton Nov. 21, 2013, 4:24 p.m. UTC | #1 
On Thu, 21 Nov 2013 12:51:43 +0100
Gregor Beck <gbeck@sernet.de> wrote:

> Hi, 
> 
> NetApp sends brocken packages in response to trans2_query_path_info with info 
> level smb_file_all_info as reported at: 
> https://bugzilla.samba.org/show_bug.cgi?id=8914
> 
> The attached patch for cifs 2.01 works around the problem by retrying the 
> operation with info levels basic and standard which yield the same 
> information. 
> 
> Thanks
> Gregor
> 

Could you repost these in the standard way?

One patch per email

Also, inlined in the email instead of as attachments, but we can work
with it if you need to send them as attachments. git-send-email is a
good tool for this, btw...
Gregor Beck Nov. 22, 2013, 10:26 a.m. UTC | #2 
Hi,

my first use of git-send-email and sendmail ;-) 

Gregor
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diff mbox

Patch

From 7b44faa24e0fc447bd76c5b97389538189f17667 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Thu, 17 Oct 2013 13:47:15 +0200
Subject: [PATCH 1/9] add struct FILE_STANDARD_INFO

---
 cifspdu.h |   10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/cifspdu.h b/cifspdu.h
index 11ca24a..89aa1f2 100644
--- a/cifspdu.h
+++ b/cifspdu.h
@@ -2233,6 +2233,16 @@  typedef struct { /* data block encoding of response to level 263 QPathInfo */
 	char FileName[1];
 } __attribute__((packed)) FILE_ALL_INFO;	/* level 0x107 QPathInfo */
 
+typedef struct {
+	__le64 AllocationSize;
+	__le64 EndOfFile;	/* size ie offset to first free byte in file */
+	__le32 NumberOfLinks;	/* hard links */
+	__u8 DeletePending;
+	__u8 Directory;
+	__u16 Pad;
+} __attribute__((packed)) FILE_STANDARD_INFO;	/* level 0x102 QPathInfo */
+
+
 /* defines for enumerating possible values of the Unix type field below */
 #define UNIX_FILE      0
 #define UNIX_DIR       1
-- 
1.7.9.5


From f82cb72e295b3bdc9c08444124681695d6b7ca07 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Mon, 21 Oct 2013 16:24:01 +0200
Subject: [PATCH 2/9] refactor CIFSSMBQPathInfo()

---
 cifssmb.c |   59 ++++++++++++++++++++++++++++++++---------------------------
 1 file changed, 32 insertions(+), 27 deletions(-)

diff --git a/cifssmb.c b/cifssmb.c
index a89c4cb..7b055fe 100644
--- a/cifssmb.c
+++ b/cifssmb.c
@@ -3958,13 +3958,13 @@  QFileInfoRetry:
 	return rc;
 }
 
-int
-CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
-		 const char *search_name, FILE_ALL_INFO *data,
-		 int legacy /* old style infolevel */,
-		 const struct nls_table *nls_codepage, int remap)
+static int
+CIFSSMBQPathInfoImpl(const unsigned int xid, struct cifs_tcon *tcon,
+		     const char *search_name,
+		     void *data, int size,
+		     __u16 level, __u16 bcc,
+		     const struct nls_table *nls_codepage, int remap)
 {
-	/* level 263 SMB_QUERY_FILE_ALL_INFO */
 	TRANSACTION2_QPI_REQ *pSMB = NULL;
 	TRANSACTION2_QPI_RSP *pSMBr = NULL;
 	int rc = 0;
@@ -3972,7 +3972,7 @@  CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 	int name_len;
 	__u16 params, byte_count;
 
-	/* cifs_dbg(FYI, "In QPathInfo path %s\n", search_name); */
+	cifs_dbg(FYI, "In QPathInfo level %u path %s", level, search_name);
 QPathInfoRetry:
 	rc = smb_init(SMB_COM_TRANSACTION2, 15, tcon, (void **) &pSMB,
 		      (void **) &pSMBr);
@@ -4011,10 +4011,7 @@  QPathInfoRetry:
 	byte_count = params + 1 /* pad */ ;
 	pSMB->TotalParameterCount = cpu_to_le16(params);
 	pSMB->ParameterCount = pSMB->TotalParameterCount;
-	if (legacy)
-		pSMB->InformationLevel = cpu_to_le16(SMB_INFO_STANDARD);
-	else
-		pSMB->InformationLevel = cpu_to_le16(SMB_QUERY_FILE_ALL_INFO);
+	pSMB->InformationLevel = level;
 	pSMB->Reserved4 = 0;
 	inc_rfc1001_len(pSMB, byte_count);
 	pSMB->ByteCount = cpu_to_le16(byte_count);
@@ -4028,25 +4025,10 @@  QPathInfoRetry:
 
 		if (rc) /* BB add auto retry on EOPNOTSUPP? */
 			rc = -EIO;
-		else if (!legacy && get_bcc(&pSMBr->hdr) < 40)
+		else if (get_bcc(&pSMBr->hdr) < bcc)
 			rc = -EIO;	/* bad smb */
-		else if (legacy && get_bcc(&pSMBr->hdr) < 24)
-			rc = -EIO;  /* 24 or 26 expected but we do not read
-					last field */
 		else if (data) {
-			int size;
 			__u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);
-
-			/*
-			 * On legacy responses we do not read the last field,
-			 * EAsize, fortunately since it varies by subdialect and
-			 * also note it differs on Set vs Get, ie two bytes or 4
-			 * bytes depending but we don't care here.
-			 */
-			if (legacy)
-				size = sizeof(FILE_INFO_STANDARD);
-			else
-				size = sizeof(FILE_ALL_INFO);
 			memcpy((char *) data, (char *) &pSMBr->hdr.Protocol +
 			       data_offset, size);
 		} else
@@ -4060,6 +4042,29 @@  QPathInfoRetry:
 }
 
 int
+CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
+		 const char *search_name, FILE_ALL_INFO *data,
+		 int legacy /* old style infolevel */,
+		 const struct nls_table *nls_codepage, int remap)
+{
+	if (legacy) {
+		/* 24 or 26 expected but on legacy responses we do not read the
+		   last field, EAsize, fortunately since it varies by subdialect
+		   and also note it differs on Set vs. Get, ie two bytes or 4
+		   bytes depending but we don't care here */
+		return CIFSSMBQPathInfoImpl(xid, tcon, search_name,
+					    data, sizeof(FILE_INFO_STANDARD),
+					    SMB_INFO_STANDARD, 24,
+					    nls_codepage, remap);
+	} else {
+		return CIFSSMBQPathInfoImpl(xid, tcon, search_name,
+					    data, sizeof(FILE_ALL_INFO),
+					    SMB_QUERY_FILE_ALL_INFO, 40,
+					    nls_codepage, remap);
+	}
+}
+
+int
 CIFSSMBUnixQFileInfo(const unsigned int xid, struct cifs_tcon *tcon,
 		 u16 netfid, FILE_UNIX_BASIC_INFO *pFindData)
 {
-- 
1.7.9.5


From e7479e89fdea3e61ef6607762e8400ed2377d68d Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Mon, 21 Oct 2013 16:28:49 +0200
Subject: [PATCH 3/9] add function CIFSSMBQPathInfoBasic()

---
 cifsproto.h |    3 +++
 cifssmb.c   |   11 +++++++++++
 2 files changed, 14 insertions(+)

diff --git a/cifsproto.h b/cifsproto.h
index b29a012..ea25d0d 100644
--- a/cifsproto.h
+++ b/cifsproto.h
@@ -240,6 +240,9 @@  extern int CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 			    const char *search_Name, FILE_ALL_INFO *data,
 			    int legacy /* whether to use old info level */,
 			    const struct nls_table *nls_codepage, int remap);
+extern int CIFSSMBQPathInfoBasic(const unsigned int xid, struct cifs_tcon *tcon,
+				 const char *search_name, FILE_BASIC_INFO *data,
+				 const struct nls_table *nls_codepage, int remap);
 extern int SMBQueryInformation(const unsigned int xid, struct cifs_tcon *tcon,
 			       const char *search_name, FILE_ALL_INFO *data,
 			       const struct nls_table *nls_codepage, int remap);
diff --git a/cifssmb.c b/cifssmb.c
index 7b055fe..d8189b5 100644
--- a/cifssmb.c
+++ b/cifssmb.c
@@ -4065,6 +4065,17 @@  CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 }
 
 int
+CIFSSMBQPathInfoBasic(const unsigned int xid, struct cifs_tcon *tcon,
+		      const char *search_name, FILE_BASIC_INFO *data,
+		      const struct nls_table *nls_codepage, int remap)
+{
+	return CIFSSMBQPathInfoImpl(xid, tcon, search_name,
+				    data, sizeof(FILE_BASIC_INFO),
+				    SMB_QUERY_FILE_BASIC_INFO, 40 /*???*/,
+				    nls_codepage, remap);
+}
+
+int
 CIFSSMBUnixQFileInfo(const unsigned int xid, struct cifs_tcon *tcon,
 		 u16 netfid, FILE_UNIX_BASIC_INFO *pFindData)
 {
-- 
1.7.9.5


From 3ccd459f7d365b22510b4461f6a671f850722791 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Mon, 21 Oct 2013 16:33:31 +0200
Subject: [PATCH 4/9] add function CIFSSMBQPathInfoStandard()

---
 cifsproto.h |    3 +++
 cifssmb.c   |   11 +++++++++++
 2 files changed, 14 insertions(+)

diff --git a/cifsproto.h b/cifsproto.h
index ea25d0d..d015336 100644
--- a/cifsproto.h
+++ b/cifsproto.h
@@ -243,6 +243,9 @@  extern int CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 extern int CIFSSMBQPathInfoBasic(const unsigned int xid, struct cifs_tcon *tcon,
 				 const char *search_name, FILE_BASIC_INFO *data,
 				 const struct nls_table *nls_codepage, int remap);
+extern int CIFSSMBQPathInfoStandard(const unsigned int xid, struct cifs_tcon *tcon,
+				    const char *search_name, FILE_STANDARD_INFO *data,
+				    const struct nls_table *nls_codepage, int remap);
 extern int SMBQueryInformation(const unsigned int xid, struct cifs_tcon *tcon,
 			       const char *search_name, FILE_ALL_INFO *data,
 			       const struct nls_table *nls_codepage, int remap);
diff --git a/cifssmb.c b/cifssmb.c
index d8189b5..38be854 100644
--- a/cifssmb.c
+++ b/cifssmb.c
@@ -4076,6 +4076,17 @@  CIFSSMBQPathInfoBasic(const unsigned int xid, struct cifs_tcon *tcon,
 }
 
 int
+CIFSSMBQPathInfoStandard(const unsigned int xid, struct cifs_tcon *tcon,
+			 const char *search_name, FILE_STANDARD_INFO *data,
+			 const struct nls_table *nls_codepage, int remap)
+{
+	return CIFSSMBQPathInfoImpl(xid, tcon, search_name,
+				    data, sizeof(FILE_STANDARD_INFO),
+				    SMB_QUERY_FILE_STANDARD_INFO, 24 /*???*/,
+				    nls_codepage, remap);
+}
+
+int
 CIFSSMBUnixQFileInfo(const unsigned int xid, struct cifs_tcon *tcon,
 		 u16 netfid, FILE_UNIX_BASIC_INFO *pFindData)
 {
-- 
1.7.9.5


From 69fca242cbd396f2446e74413ff8906a04ad56d7 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Mon, 21 Oct 2013 17:02:52 +0200
Subject: [PATCH 5/9] fallback to CIFSSMBQPathInfoBasic() in
 cifs_is_path_accessible()

---
 smb1ops.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/smb1ops.c b/smb1ops.c
index 6094397..635b1e5 100644
--- a/smb1ops.c
+++ b/smb1ops.c
@@ -513,20 +513,23 @@  cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
 {
 	int rc;
 	FILE_ALL_INFO *file_info;
+	const int remap = cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR;
 
 	file_info = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 	if (file_info == NULL)
 		return -ENOMEM;
 
 	rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
-			      0 /* not legacy */, cifs_sb->local_nls,
-			      cifs_sb->mnt_cifs_flags &
-				CIFS_MOUNT_MAP_SPECIAL_CHR);
+			      0 /* not legacy */, cifs_sb->local_nls, remap);
+	if (rc == -EIO) {
+		rc = CIFSSMBQPathInfoBasic(xid, tcon, full_path,
+					   (FILE_BASIC_INFO*)file_info,
+					   cifs_sb->local_nls, remap);
+	}
 
 	if (rc == -EOPNOTSUPP || rc == -EINVAL)
 		rc = SMBQueryInformation(xid, tcon, full_path, file_info,
-				cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
-				  CIFS_MOUNT_MAP_SPECIAL_CHR);
+					 cifs_sb->local_nls, remap);
 	kfree(file_info);
 	return rc;
 }
-- 
1.7.9.5


From c36dda3c9901daa0f7ff4fa920a4ee19246a0e55 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Tue, 22 Oct 2013 09:52:59 +0200
Subject: [PATCH 6/9] fallback to CIFSSMBQPathInfoBasic()/Standard() in
 cifs_is_path_accessible()

---
 smb1ops.c |   20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/smb1ops.c b/smb1ops.c
index 635b1e5..a12e370 100644
--- a/smb1ops.c
+++ b/smb1ops.c
@@ -540,11 +540,23 @@  cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 		     FILE_ALL_INFO *data, bool *adjustTZ)
 {
 	int rc;
+	const int remap = cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR;
 
 	/* could do find first instead but this returns more info */
 	rc = CIFSSMBQPathInfo(xid, tcon, full_path, data, 0 /* not legacy */,
-			      cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
-						CIFS_MOUNT_MAP_SPECIAL_CHR);
+			      cifs_sb->local_nls, remap);
+
+	if (rc == -EIO) {
+		rc = CIFSSMBQPathInfoBasic(xid, tcon, full_path,
+					   (FILE_BASIC_INFO*)data,
+					   cifs_sb->local_nls, remap);
+		if (!rc) {
+			rc = CIFSSMBQPathInfoStandard(xid, tcon, full_path,
+						      (void*)data + sizeof(FILE_BASIC_INFO),
+						      cifs_sb->local_nls, remap);
+		}
+	}
+
 	/*
 	 * BB optimize code so we do not make the above call when server claims
 	 * no NT SMB support and the above call failed at least once - set flag
@@ -552,9 +564,7 @@  cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 	 */
 	if ((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
 		rc = SMBQueryInformation(xid, tcon, full_path, data,
-					 cifs_sb->local_nls,
-					 cifs_sb->mnt_cifs_flags &
-						CIFS_MOUNT_MAP_SPECIAL_CHR);
+					 cifs_sb->local_nls, remap);
 		*adjustTZ = true;
 	}
 	return rc;
-- 
1.7.9.5


From f53227ee3349f91412de23f9db49da251679e043 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Tue, 22 Oct 2013 10:01:40 +0200
Subject: [PATCH 7/9] fix some cFYI in cifssmb.c

---
 cifssmb.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/cifssmb.c b/cifssmb.c
index 38be854..5d10afc 100644
--- a/cifssmb.c
+++ b/cifssmb.c
@@ -3935,7 +3935,7 @@  QFileInfoRetry:
 	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
 			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
 	if (rc) {
-		cifs_dbg(FYI, "Send error in QPathInfo = %d\n", rc);
+		cifs_dbg(FYI, "Send error in QFileInfo = %d", rc);
 	} else {		/* decode response */
 		rc = validate_t2((struct smb_t2_rsp *)pSMBr);
 
@@ -4131,7 +4131,7 @@  UnixQFileInfoRetry:
 	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
 			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
 	if (rc) {
-		cifs_dbg(FYI, "Send error in QPathInfo = %d\n", rc);
+		cifs_dbg(FYI, "Send error in UnixQFileInfo = %d", rc);
 	} else {		/* decode response */
 		rc = validate_t2((struct smb_t2_rsp *)pSMBr);
 
@@ -4215,7 +4215,7 @@  UnixQPathInfoRetry:
 	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
 			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
 	if (rc) {
-		cifs_dbg(FYI, "Send error in QPathInfo = %d\n", rc);
+		cifs_dbg(FYI, "Send error in UnixQPathInfo = %d", rc);
 	} else {		/* decode response */
 		rc = validate_t2((struct smb_t2_rsp *)pSMBr);
 
-- 
1.7.9.5


From f13f9d5ca298da2d6f40059a6169fb8504427e0b Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Tue, 22 Oct 2013 11:02:57 +0200
Subject: [PATCH 8/9] cFYI

---
 smb1ops.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/smb1ops.c b/smb1ops.c
index a12e370..11daa28 100644
--- a/smb1ops.c
+++ b/smb1ops.c
@@ -522,6 +522,7 @@  cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
 	rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
 			      0 /* not legacy */, cifs_sb->local_nls, remap);
 	if (rc == -EIO) {
+		cifs_dbg(FYI, "is_path_accessible: FALLBACK");
 		rc = CIFSSMBQPathInfoBasic(xid, tcon, full_path,
 					   (FILE_BASIC_INFO*)file_info,
 					   cifs_sb->local_nls, remap);
@@ -547,6 +548,7 @@  cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 			      cifs_sb->local_nls, remap);
 
 	if (rc == -EIO) {
+		cifs_dbg(FYI, "cifs_query_path_info: FALLBACK");
 		rc = CIFSSMBQPathInfoBasic(xid, tcon, full_path,
 					   (FILE_BASIC_INFO*)data,
 					   cifs_sb->local_nls, remap);
-- 
1.7.9.5


From 95a15de52fff01fc0875dfa246842b06698525c5 Mon Sep 17 00:00:00 2001
From: Gregor Beck <gbeck@sernet.de>
Date: Wed, 30 Oct 2013 14:14:52 +0100
Subject: [PATCH 9/9] cache we have broken_qpath_info per tcon

---
 cifsglob.h |    1 +
 smb1ops.c  |   26 ++++++++++++++++++--------
 2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/cifsglob.h b/cifsglob.h
index 52ca861..d3adde7 100644
--- a/cifsglob.h
+++ b/cifsglob.h
@@ -818,6 +818,7 @@  struct cifs_tcon {
 	bool local_lease:1; /* check leases (only) on local system not remote */
 	bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */
 	bool need_reconnect:1; /* connection reset, tid now invalid */
+	bool broken_qpath_info:1;
 #ifdef CONFIG_CIFS_SMB2
 	bool print:1;		/* set if connection to printer share */
 	bool bad_network_name:1; /* set if ret status STATUS_BAD_NETWORK_NAME */
diff --git a/smb1ops.c b/smb1ops.c
index 11daa28..e3798a4 100644
--- a/smb1ops.c
+++ b/smb1ops.c
@@ -511,7 +511,7 @@  static int
 cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
 			struct cifs_sb_info *cifs_sb, const char *full_path)
 {
-	int rc;
+	int rc= -EIO;
 	FILE_ALL_INFO *file_info;
 	const int remap = cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR;
 
@@ -519,13 +519,18 @@  cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
 	if (file_info == NULL)
 		return -ENOMEM;
 
-	rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
-			      0 /* not legacy */, cifs_sb->local_nls, remap);
+	if (!tcon->broken_qpath_info) {
+		rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
+				      0, cifs_sb->local_nls, remap);
+	}
 	if (rc == -EIO) {
-		cifs_dbg(FYI, "is_path_accessible: FALLBACK");
 		rc = CIFSSMBQPathInfoBasic(xid, tcon, full_path,
 					   (FILE_BASIC_INFO*)file_info,
 					   cifs_sb->local_nls, remap);
+		cifs_dbg(FYI, "is_path_accessible: FALLBACK returns %d", rc);
+		if (!rc) {
+			tcon->broken_qpath_info = true;
+		}
 	}
 
 	if (rc == -EOPNOTSUPP || rc == -EINVAL)
@@ -540,15 +545,16 @@  cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 		     struct cifs_sb_info *cifs_sb, const char *full_path,
 		     FILE_ALL_INFO *data, bool *adjustTZ)
 {
-	int rc;
+	int rc = -EIO;
 	const int remap = cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR;
 
 	/* could do find first instead but this returns more info */
-	rc = CIFSSMBQPathInfo(xid, tcon, full_path, data, 0 /* not legacy */,
-			      cifs_sb->local_nls, remap);
+	if (!tcon->broken_qpath_info) {
+		rc = CIFSSMBQPathInfo(xid, tcon, full_path, data, 0,
+				      cifs_sb->local_nls, remap);
+	}
 
 	if (rc == -EIO) {
-		cifs_dbg(FYI, "cifs_query_path_info: FALLBACK");
 		rc = CIFSSMBQPathInfoBasic(xid, tcon, full_path,
 					   (FILE_BASIC_INFO*)data,
 					   cifs_sb->local_nls, remap);
@@ -557,6 +563,10 @@  cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 						      (void*)data + sizeof(FILE_BASIC_INFO),
 						      cifs_sb->local_nls, remap);
 		}
+		cifs_dbg(FYI, "cifs_query_path_info: FALLBACK returns %d", rc);
+		if (!rc) {
+			tcon->broken_qpath_info = true;
+		}
 	}
 
 	/*
-- 
1.7.9.5