[PATCH 1/2] xl: uptime: skip dom0 when calling print_domU_uptime

[PATCH 1/2] xl: uptime: skip dom0 when calling print_domU_uptime

[Ian Campbell]

Dom0 is handled separately (via print_dom0_uptime) and the domU
variant doesn't work for dom0 since libxl_vm_get_start_time() doesn't.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
 tools/libxl/xl_cmdimpl.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
index f38e3dd..89fa42c 100644
--- a/tools/libxl/xl_cmdimpl.c
+++ b/tools/libxl/xl_cmdimpl.c
@@ -7055,8 +7055,10 @@ static void print_uptime(int short_mode, uint32_t doms[], int nb_doms)
             fprintf(stderr, "Could not list vms.\n");
             return;
         }
-        for (i = 0; i < nb_vm; i++)
+        for (i = 0; i < nb_vm; i++) {
+            if (info[i].domid == 0) continue;
             print_domU_uptime(info[i].domid, short_mode, now);
+        }
         libxl_vminfo_list_free(info, nb_vm);
     } else {
         for (i = 0; i < nb_doms; i++) {
-- 
2.1.4

[PATCH 2/2] xl: NULL terminate buf when reading dom0 /proc/uptime

[Ian Campbell]

The contents of /proc/uptime is typically something like "80164.57
640617.58", so the existing 512 byte buffer is more than large enoguh,
so reduce its effective size to 511 bytes and ensure we include a
NULL.

Otherwise Coverity points out that we pass a potentially unterminated
string to strtok. In practice this likely doesn't actually cause
issues (at least on Linux) because the
string should always contain a space so we will stop parsing.

CID: 105590

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
 tools/libxl/xl_cmdimpl.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
index 89fa42c..31cea0f 100644
--- a/tools/libxl/xl_cmdimpl.c
+++ b/tools/libxl/xl_cmdimpl.c
@@ -6959,6 +6959,7 @@ static char *current_time_to_string(time_t now)
 static void print_dom0_uptime(int short_mode, time_t now)
 {
     int fd;
+    ssize_t nr;
     char buf[512];
     uint32_t uptime = 0;
     char *uptime_str = NULL;
@@ -6969,12 +6970,15 @@ static void print_dom0_uptime(int short_mode, time_t now)
     if (fd == -1)
         goto err;
 
-    if (read(fd, buf, sizeof(buf)) == -1) {
+    nr = read(fd, buf, sizeof(buf) - 1);
+    if (nr == -1) {
         close(fd);
         goto err;
     }
     close(fd);
 
+    buf[nr] = '\0';
+
     strtok(buf, " ");
     uptime = strtoul(buf, NULL, 10);
 
-- 
2.1.4

Re: [PATCH 1/2] xl: uptime: skip dom0 when calling print_domU_uptime

[Ian Campbell]

On Wed, 2016-02-17 at 10:34 +0000, Ian Campbell wrote:
> Dom0 is handled separately (via print_dom0_uptime) and the domU
> variant doesn't work for dom0 since libxl_vm_get_start_time() doesn't.
> 
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>

Ping? (and for 2/2 "xl: NULL terminate buf when reading dom0 /proc/uptime")


> ---
>  tools/libxl/xl_cmdimpl.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
> index f38e3dd..89fa42c 100644
> --- a/tools/libxl/xl_cmdimpl.c
> +++ b/tools/libxl/xl_cmdimpl.c
> @@ -7055,8 +7055,10 @@ static void print_uptime(int short_mode, uint32_t
> doms[], int nb_doms)
>              fprintf(stderr, "Could not list vms.\n");
>              return;
>          }
> -        for (i = 0; i < nb_vm; i++)
> +        for (i = 0; i < nb_vm; i++) {
> +            if (info[i].domid == 0) continue;
>              print_domU_uptime(info[i].domid, short_mode, now);
> +        }
>          libxl_vminfo_list_free(info, nb_vm);
>      } else {
>          for (i = 0; i < nb_doms; i++) {
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Re: [PATCH 1/2] xl: uptime: skip dom0 when calling print_domU_uptime

[Ian Jackson]

Ian Campbell writes ("[PATCH 1/2] xl: uptime: skip dom0 when calling print_domU_uptime"):
> Dom0 is handled separately (via print_dom0_uptime) and the domU
> variant doesn't work for dom0 since libxl_vm_get_start_time() doesn't.
> 
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>

Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

and queued

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Re: [PATCH 2/2] xl: NULL terminate buf when reading dom0 /proc/uptime

[Ian Jackson]

Ian Campbell writes ("[PATCH 2/2] xl: NULL terminate buf when reading dom0 /proc/uptime"):
> The contents of /proc/uptime is typically something like "80164.57
> 640617.58", so the existing 512 byte buffer is more than large enoguh,
> so reduce its effective size to 511 bytes and ensure we include a
> NULL.
> 
> Otherwise Coverity points out that we pass a potentially unterminated
> string to strtok. In practice this likely doesn't actually cause
> issues (at least on Linux) because the
> string should always contain a space so we will stop parsing.

Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

and queued

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