[PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[Olaf Hering]

This change fixes a few compile errors:

hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
hv_vss_daemon.c: In function 'vss_operate':
hv_vss_daemon.c:66: warning: 'return' with no value, in function returning non-void
hv_vss_daemon.c: In function 'main':
hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared with attribute warn_unused_result
hv_vss_daemon.c: In function 'vss_operate':
hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 tools/hv/hv_vss_daemon.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
index 9526995..2a03d0b 100644
--- a/tools/hv/hv_vss_daemon.c
+++ b/tools/hv/hv_vss_daemon.c
@@ -51,7 +51,7 @@ static int vss_operate(int operation)
 	FILE *file;
 	char *p;
 	char *x;
-	int error;
+	int error = 0;
 
 	switch (operation) {
 	case VSS_OP_FREEZE:
@@ -60,11 +60,13 @@ static int vss_operate(int operation)
 	case VSS_OP_THAW:
 		fs_op = "-u ";
 		break;
+	default:
+		return -1;
 	}
 
-	file = popen("mount | awk '/^\/dev\// { print $3}'", "r");
+	file = popen("mount | awk '/^\\/dev\\// { print $3}'", "r");
 	if (file == NULL)
-		return;
+		return -1;
 
 	while ((p = fgets(buf, sizeof(buf), file)) != NULL) {
 		x = strchr(p, '\n');
@@ -128,7 +130,9 @@ int main(void)
 	int	op;
 	struct hv_vss_msg *vss_msg;
 
-	daemon(1, 0);
+	if (daemon(1, 0))
+		return 1;
+
 	openlog("Hyper-V VSS", 0, LOG_USER);
 	syslog(LOG_INFO, "VSS starting; pid is:%d", getpid());
 

[PATCH 2/3] tools: hv: fix checks for origin of netlink message in hv_vss_daemon

[Olaf Hering]

Similar to what commit 95a69adab9acfc3981c504737a2b6578e4d846ef ("tools:
hv: Netlink source address validation allows DoS") does in
hv_kvp_daemon, improve checks for origin of netlink connector message.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 tools/hv/hv_vss_daemon.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
index 2a03d0b..dc3eb1e 100644
--- a/tools/hv/hv_vss_daemon.c
+++ b/tools/hv/hv_vss_daemon.c
@@ -186,13 +186,19 @@ int main(void)
 		len = recvfrom(fd, vss_recv_buffer, sizeof(vss_recv_buffer), 0,
 				addr_p, &addr_l);
 
-		if (len < 0 || addr.nl_pid) {
+		if (len < 0) {
 			syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
 					addr.nl_pid, errno, strerror(errno));
 			close(fd);
 			return -1;
 		}
 
+		if (addr.nl_pid) {
+			syslog(LOG_WARNING, "Received packet from untrusted pid:%u",
+					addr.nl_pid);
+			continue;
+		}
+
 		incoming_msg = (struct nlmsghdr *)vss_recv_buffer;
 
 		if (incoming_msg->nlmsg_type != NLMSG_DONE)

[PATCH 3/3] tools: hv: use getmntent in hv_vss_daemon

[Olaf Hering]

As suggested by Paolo Bonzini, use getmntent instead of parsing output
of mount(1).

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 tools/hv/hv_vss_daemon.c | 39 +++++++++++++++++++++------------------
 1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
index dc3eb1e..e37d86c 100644
--- a/tools/hv/hv_vss_daemon.c
+++ b/tools/hv/hv_vss_daemon.c
@@ -23,6 +23,7 @@
 #include <sys/poll.h>
 #include <linux/types.h>
 #include <stdio.h>
+#include <mntent.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <string.h>
@@ -47,11 +48,10 @@ static int vss_operate(int operation)
 {
 	char *fs_op;
 	char cmd[512];
-	char buf[512];
-	FILE *file;
-	char *p;
-	char *x;
-	int error = 0;
+	char match[] = "/dev/";
+	FILE *mounts;
+	struct mntent *ent;
+	int error = 0, root_seen = 0;
 
 	switch (operation) {
 	case VSS_OP_FREEZE:
@@ -64,25 +64,28 @@ static int vss_operate(int operation)
 		return -1;
 	}
 
-	file = popen("mount | awk '/^\\/dev\\// { print $3}'", "r");
-	if (file == NULL)
+	mounts = setmntent("/proc/mounts", "r");
+	if (mounts == NULL)
 		return -1;
 
-	while ((p = fgets(buf, sizeof(buf), file)) != NULL) {
-		x = strchr(p, '\n');
-		*x = '\0';
-		if (!strncmp(p, "/", sizeof("/")))
+	while((ent = getmntent(mounts))) {
+		if (strncmp(ent->mnt_fsname, match, strlen(match)))
 			continue;
-
-		sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, p);
+		if (strcmp(ent->mnt_dir, "/") == 0) {
+			root_seen = 1;
+			continue;
+		}
+		snprintf(cmd, sizeof(cmd), "fsfreeze %s '%s'", fs_op, ent->mnt_dir);
 		syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
-		error = system(cmd);
+		error |= system(cmd);
 	}
-	pclose(file);
+	endmntent(mounts);
 
-	sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, "/");
-	syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
-	error = system(cmd);
+	if (root_seen) {
+		sprintf(cmd, "fsfreeze %s /", fs_op);
+		syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
+		error |= system(cmd);
+	}
 
 	return error;
 }

RE: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[KY Srinivasan]

> -----Original Message-----
> From: Olaf Hering [mailto:olaf@aepfle.de]
> Sent: Tuesday, March 26, 2013 11:28 AM
> To: KY Srinivasan; gregkh@linuxfoundation.org
> Cc: linux-kernel@vger.kernel.org; Olaf Hering
> Subject: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon
> 
> This change fixes a few compile errors:
> 
> hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> hv_vss_daemon.c: In function 'vss_operate':
> hv_vss_daemon.c:66: warning: 'return' with no value, in function returning non-
> void
> hv_vss_daemon.c: In function 'main':
> hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared with
> attribute warn_unused_result
> hv_vss_daemon.c: In function 'vss_operate':
> hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function
> 
> Signed-off-by: Olaf Hering <olaf@aepfle.de>
Thanks for fixing this.

Acked by: K. Y. Srinivasan <kys@microsoft.com>
> ---
>  tools/hv/hv_vss_daemon.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
> index 9526995..2a03d0b 100644
> --- a/tools/hv/hv_vss_daemon.c
> +++ b/tools/hv/hv_vss_daemon.c
> @@ -51,7 +51,7 @@ static int vss_operate(int operation)
>  	FILE *file;
>  	char *p;
>  	char *x;
> -	int error;
> +	int error = 0;
> 
>  	switch (operation) {
>  	case VSS_OP_FREEZE:
> @@ -60,11 +60,13 @@ static int vss_operate(int operation)
>  	case VSS_OP_THAW:
>  		fs_op = "-u ";
>  		break;
> +	default:
> +		return -1;
>  	}
> 
> -	file = popen("mount | awk '/^\/dev\// { print $3}'", "r");
> +	file = popen("mount | awk '/^\\/dev\\// { print $3}'", "r");
>  	if (file == NULL)
> -		return;
> +		return -1;
> 
>  	while ((p = fgets(buf, sizeof(buf), file)) != NULL) {
>  		x = strchr(p, '\n');
> @@ -128,7 +130,9 @@ int main(void)
>  	int	op;
>  	struct hv_vss_msg *vss_msg;
> 
> -	daemon(1, 0);
> +	if (daemon(1, 0))
> +		return 1;
> +
>  	openlog("Hyper-V VSS", 0, LOG_USER);
>  	syslog(LOG_INFO, "VSS starting; pid is:%d", getpid());
> 
> 

RE: [PATCH 2/3] tools: hv: fix checks for origin of netlink message in hv_vss_daemon

[KY Srinivasan]

> -----Original Message-----
> From: Olaf Hering [mailto:olaf@aepfle.de]
> Sent: Tuesday, March 26, 2013 11:28 AM
> To: KY Srinivasan; gregkh@linuxfoundation.org
> Cc: linux-kernel@vger.kernel.org; Olaf Hering
> Subject: [PATCH 2/3] tools: hv: fix checks for origin of netlink message in
> hv_vss_daemon
> 
> Similar to what commit 95a69adab9acfc3981c504737a2b6578e4d846ef ("tools:
> hv: Netlink source address validation allows DoS") does in
> hv_kvp_daemon, improve checks for origin of netlink connector message.
> 
> Signed-off-by: Olaf Hering <olaf@aepfle.de>

Acked by: K. Y. Srinivasan <kys@microsoft.com>
> ---
>  tools/hv/hv_vss_daemon.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
> index 2a03d0b..dc3eb1e 100644
> --- a/tools/hv/hv_vss_daemon.c
> +++ b/tools/hv/hv_vss_daemon.c
> @@ -186,13 +186,19 @@ int main(void)
>  		len = recvfrom(fd, vss_recv_buffer, sizeof(vss_recv_buffer), 0,
>  				addr_p, &addr_l);
> 
> -		if (len < 0 || addr.nl_pid) {
> +		if (len < 0) {
>  			syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
>  					addr.nl_pid, errno, strerror(errno));
>  			close(fd);
>  			return -1;
>  		}
> 
> +		if (addr.nl_pid) {
> +			syslog(LOG_WARNING, "Received packet from untrusted
> pid:%u",
> +					addr.nl_pid);
> +			continue;
> +		}
> +
>  		incoming_msg = (struct nlmsghdr *)vss_recv_buffer;
> 
>  		if (incoming_msg->nlmsg_type != NLMSG_DONE)
> 

RE: [PATCH 3/3] tools: hv: use getmntent in hv_vss_daemon

[KY Srinivasan]

> -----Original Message-----
> From: Olaf Hering [mailto:olaf@aepfle.de]
> Sent: Tuesday, March 26, 2013 11:28 AM
> To: KY Srinivasan; gregkh@linuxfoundation.org
> Cc: linux-kernel@vger.kernel.org; Olaf Hering
> Subject: [PATCH 3/3] tools: hv: use getmntent in hv_vss_daemon
> 
> As suggested by Paolo Bonzini, use getmntent instead of parsing output
> of mount(1).
> 
> Signed-off-by: Olaf Hering <olaf@aepfle.de>

Thanks for addressing this.

Acked by: K. Y. Srinivasan <kys@microsoft.com>
> ---
>  tools/hv/hv_vss_daemon.c | 39 +++++++++++++++++++++------------------
>  1 file changed, 21 insertions(+), 18 deletions(-)
> 
> diff --git a/tools/hv/hv_vss_daemon.c b/tools/hv/hv_vss_daemon.c
> index dc3eb1e..e37d86c 100644
> --- a/tools/hv/hv_vss_daemon.c
> +++ b/tools/hv/hv_vss_daemon.c
> @@ -23,6 +23,7 @@
>  #include <sys/poll.h>
>  #include <linux/types.h>
>  #include <stdio.h>
> +#include <mntent.h>
>  #include <stdlib.h>
>  #include <unistd.h>
>  #include <string.h>
> @@ -47,11 +48,10 @@ static int vss_operate(int operation)
>  {
>  	char *fs_op;
>  	char cmd[512];
> -	char buf[512];
> -	FILE *file;
> -	char *p;
> -	char *x;
> -	int error = 0;
> +	char match[] = "/dev/";
> +	FILE *mounts;
> +	struct mntent *ent;
> +	int error = 0, root_seen = 0;
> 
>  	switch (operation) {
>  	case VSS_OP_FREEZE:
> @@ -64,25 +64,28 @@ static int vss_operate(int operation)
>  		return -1;
>  	}
> 
> -	file = popen("mount | awk '/^\\/dev\\// { print $3}'", "r");
> -	if (file == NULL)
> +	mounts = setmntent("/proc/mounts", "r");
> +	if (mounts == NULL)
>  		return -1;
> 
> -	while ((p = fgets(buf, sizeof(buf), file)) != NULL) {
> -		x = strchr(p, '\n');
> -		*x = '\0';
> -		if (!strncmp(p, "/", sizeof("/")))
> +	while((ent = getmntent(mounts))) {
> +		if (strncmp(ent->mnt_fsname, match, strlen(match)))
>  			continue;
> -
> -		sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, p);
> +		if (strcmp(ent->mnt_dir, "/") == 0) {
> +			root_seen = 1;
> +			continue;
> +		}
> +		snprintf(cmd, sizeof(cmd), "fsfreeze %s '%s'", fs_op, ent-
> >mnt_dir);
>  		syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
> -		error = system(cmd);
> +		error |= system(cmd);
>  	}
> -	pclose(file);
> +	endmntent(mounts);
> 
> -	sprintf(cmd, "%s %s %s", "fsfreeze ", fs_op, "/");
> -	syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
> -	error = system(cmd);
> +	if (root_seen) {
> +		sprintf(cmd, "fsfreeze %s /", fs_op);
> +		syslog(LOG_INFO, "VSS cmd is %s\n", cmd);
> +		error |= system(cmd);
> +	}
> 
>  	return error;
>  }
> 

Re: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[Greg KH]

On Tue, Mar 26, 2013 at 04:28:27PM +0100, Olaf Hering wrote:
> This change fixes a few compile errors:
> 
> hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> hv_vss_daemon.c: In function 'vss_operate':
> hv_vss_daemon.c:66: warning: 'return' with no value, in function returning non-void
> hv_vss_daemon.c: In function 'main':
> hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared with attribute warn_unused_result
> hv_vss_daemon.c: In function 'vss_operate':
> hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function
> 
> Signed-off-by: Olaf Hering <olaf@aepfle.de>

For some reason, all of your hv tools patches ended up in my spam
filter.  KY, can you resend me any that I didn't apply, and you have
tested?

thanks,

greg k-h

RE: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[KY Srinivasan]

> -----Original Message-----
> From: Greg KH [mailto:gregkh@linuxfoundation.org]
> Sent: Friday, April 19, 2013 7:24 PM
> To: Olaf Hering
> Cc: KY Srinivasan; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon
> 
> On Tue, Mar 26, 2013 at 04:28:27PM +0100, Olaf Hering wrote:
> > This change fixes a few compile errors:
> >
> > hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> > hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> > hv_vss_daemon.c: In function 'vss_operate':
> > hv_vss_daemon.c:66: warning: 'return' with no value, in function returning
> non-void
> > hv_vss_daemon.c: In function 'main':
> > hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared
> with attribute warn_unused_result
> > hv_vss_daemon.c: In function 'vss_operate':
> > hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function
> >
> > Signed-off-by: Olaf Hering <olaf@aepfle.de>
> 
> For some reason, all of your hv tools patches ended up in my spam
> filter.  KY, can you resend me any that I didn't apply, and you have
> tested?

Greg,

I forwarded some patches from Olaf (I think Olaf is on vacation) that have not been applied. I had acked all these patches when Olaf sent them out initially.

Regards,

K. Y
> 
> thanks,
> 
> greg k-h
> 

Re: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[Greg KH]

On Sun, Apr 21, 2013 at 10:32:45PM +0000, KY Srinivasan wrote:
> 
> > -----Original Message-----
> > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > Sent: Friday, April 19, 2013 7:24 PM
> > To: Olaf Hering
> > Cc: KY Srinivasan; linux-kernel@vger.kernel.org
> > Subject: Re: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon
> > 
> > On Tue, Mar 26, 2013 at 04:28:27PM +0100, Olaf Hering wrote:
> > > This change fixes a few compile errors:
> > >
> > > hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> > > hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> > > hv_vss_daemon.c: In function 'vss_operate':
> > > hv_vss_daemon.c:66: warning: 'return' with no value, in function returning
> > non-void
> > > hv_vss_daemon.c: In function 'main':
> > > hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared
> > with attribute warn_unused_result
> > > hv_vss_daemon.c: In function 'vss_operate':
> > > hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function
> > >
> > > Signed-off-by: Olaf Hering <olaf@aepfle.de>
> > 
> > For some reason, all of your hv tools patches ended up in my spam
> > filter.  KY, can you resend me any that I didn't apply, and you have
> > tested?
> 
> Greg,
> 
> I forwarded some patches from Olaf (I think Olaf is on vacation) that
> have not been applied. I had acked all these patches when Olaf sent
> them out initially.

Can you please resend them in a format that I can apply them in (hint,
I should never have to edit the patch by hand from you.)

thanks,

greg k-h

RE: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon

[KY Srinivasan]

> -----Original Message-----
> From: Greg KH [mailto:gregkh@linuxfoundation.org]
> Sent: Sunday, April 21, 2013 9:13 PM
> To: KY Srinivasan
> Cc: Olaf Hering; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon
> 
> On Sun, Apr 21, 2013 at 10:32:45PM +0000, KY Srinivasan wrote:
> >
> > > -----Original Message-----
> > > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > > Sent: Friday, April 19, 2013 7:24 PM
> > > To: Olaf Hering
> > > Cc: KY Srinivasan; linux-kernel@vger.kernel.org
> > > Subject: Re: [PATCH 1/3] Tools: hv: fix warnings in hv_vss_daemon
> > >
> > > On Tue, Mar 26, 2013 at 04:28:27PM +0100, Olaf Hering wrote:
> > > > This change fixes a few compile errors:
> > > >
> > > > hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> > > > hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
> > > > hv_vss_daemon.c: In function 'vss_operate':
> > > > hv_vss_daemon.c:66: warning: 'return' with no value, in function returning
> > > non-void
> > > > hv_vss_daemon.c: In function 'main':
> > > > hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared
> > > with attribute warn_unused_result
> > > > hv_vss_daemon.c: In function 'vss_operate':
> > > > hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this
> function
> > > >
> > > > Signed-off-by: Olaf Hering <olaf@aepfle.de>
> > >
> > > For some reason, all of your hv tools patches ended up in my spam
> > > filter.  KY, can you resend me any that I didn't apply, and you have
> > > tested?
> >
> > Greg,
> >
> > I forwarded some patches from Olaf (I think Olaf is on vacation) that
> > have not been applied. I had acked all these patches when Olaf sent
> > them out initially.
> 
> Can you please resend them in a format that I can apply them in (hint,
> I should never have to edit the patch by hand from you.)

Done.

K. Y
> 
> thanks,
> 
> greg k-h
>