[PATCH v3 1/4] xen-livepatch: fix parameter name parsing

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

It's incorrect to restrict strncmp to the length of the command line input
parameter, as then a user passing a rune like:

% xen-livepatch up foo.livepatch

Would match against the "upload" command, because the string comparison has
been truncated to the length of the input argument.  Instead the truncation
should be done based on the length of the command name stored in the internal
array of actions.

Fixes: 05bb8afedede ('xen-xsplice: Tool to manipulate xsplice payloads')
Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
Changes since v2:
 - New in this version.
---
 tools/misc/xen-livepatch.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/misc/xen-livepatch.c b/tools/misc/xen-livepatch.c
index 5bf9d9a32b65..a246e5dfd38e 100644
--- a/tools/misc/xen-livepatch.c
+++ b/tools/misc/xen-livepatch.c
@@ -572,13 +572,15 @@ int main(int argc, char *argv[])
         return 0;
     }
     for ( i = 0; i < ARRAY_SIZE(main_options); i++ )
-        if (!strncmp(main_options[i].name, argv[1], strlen(argv[1])))
+        if (!strncmp(main_options[i].name, argv[1],
+                     strlen(main_options[i].name)))
             break;
 
     if ( i == ARRAY_SIZE(main_options) )
     {
         for ( j = 0; j < ARRAY_SIZE(action_options); j++ )
-            if (!strncmp(action_options[j].name, argv[1], strlen(argv[1])))
+            if (!strncmp(action_options[j].name, argv[1],
+                         strlen(action_options[j].name)))
                 break;
 
         if ( j == ARRAY_SIZE(action_options) )
-- 
2.44.0