From cad39264b6651b6f2824c46ea73d77764235f3d9 Mon Sep 17 00:00:00 2001
From: Andrew Deason <adeason@sinenomine.net>
Date: Fri, 29 Sep 2023 16:16:49 -0500
Subject: [PATCH] fs: Get parent dir cell for 'fs getfid -literal'

After we get the fid for the requested path, 'fs getfid' then gets the
cell for the path:

    GetCell(ti->data, cell);

But ti->data is the full path requested, whether -literal was given or
not. If the given path ends with a broken symlink/mountpoint or
nonexistent fid, we've already gotten the fid (if -literal was given)
but we'll still exit with an (often confusing) error:

    $ fs getfid symlink.broken -literal
    fs: no such cell as 'symlink.broken'

In addition, if we use 'fs getfid -literal' to get the fid of a
cross-cell mountpoint object, we'll get the wrong cell. We'll report
the cell of the mountpoint's target, instead of the cell of the
reported fid:

    $ fs getfid /afs/example.com -literal
    File /afs/example.com (1.16777244.1) located in cell example.com

To fix these, pass 'parent_dir' to GetCell() when -literal is given.
To do this, we need to not free parent_dir until later, so reorganize
the 'parent_dir' and 'last_component' vars to be freed at the end of
the loop, and change the 'continue' code paths to goto the end of the
loop instead.

With this, the cell is now reported properly for these cases:

    $ fs getfid symlink.broken -literal
    File symlink.broken (536871063.22.865) located in cell example.com

    $ fs getfid /afs/example.com -literal
    File /afs/example.com (1.16777244.1) located in cell dynroot

Change-Id: I8ec297dae84f677d530b6f7c39786f18c2a9c50f
Reviewed-on: https://gerrit.openafs.org/15584
Reviewed-by: Mark Vitale <mvitale@sinenomine.net>
Reviewed-by: Marcio Brito Barbosa <mbarbosa@sinenomine.net>
Reviewed-by: Cheyenne Wills <cwills@sinenomine.net>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
---
 src/venus/fs.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/venus/fs.c b/src/venus/fs.c
index e07a07f6e3..d4a512fd41 100644
--- a/src/venus/fs.c
+++ b/src/venus/fs.c
@@ -4261,50 +4261,54 @@ GetFidCmd(struct cmd_syndesc *as, void *arock)
     }
     for (ti = as->parms[0].items; ti; ti = ti->next) {
         struct VenusFid vfid;
+	char *parent_dir = NULL;
+	char *last_component = NULL;
 
         blob.out_size = sizeof(struct VenusFid);
         blob.out = (char *) &vfid;
         blob.in_size = 0;
 
 	if (literal) {
-	    char *parent_dir = NULL;
-	    char *last_component = NULL;
-
 	    if (GetLastComponent(ti->data, &parent_dir,
 				 &last_component, NULL, literal) != 0) {
 		error = 1;
-		continue;
+		goto next_item;
 	    }
 
 	    blob.in = last_component;
 	    blob.in_size = strlen(last_component) + 1;
 	    code = pioctl(parent_dir, VIOC_GETLITERALFID, &blob, 1);
 
-	    free(parent_dir);
-	    free(last_component);
 	} else {
 	    code = pioctl(ti->data, VIOCGETFID, &blob, 1);
 	}
         if (code) {
             Die(errno,ti->data);
             error = 1;
-            continue;
+	    goto next_item;
         }
 
-        code = GetCell(ti->data, cell);
+	if (literal) {
+	    code = GetCell(parent_dir, cell);
+	} else {
+	    code = GetCell(ti->data, cell);
+	}
         if (code) {
 	    if (errno == ENOENT)
 		fprintf(stderr, "%s: no such cell as '%s'\n", pn, ti->data);
 	    else
 		Die(errno, ti->data);
 	    error = 1;
-	    continue;
+	    goto next_item;
         }
 
         printf("File %s (%u.%u.%u) located in cell %s\n",
                ti->data, vfid.Fid.Volume, vfid.Fid.Vnode, vfid.Fid.Unique,
                cell);
 
+ next_item:
+	free(parent_dir);
+	free(last_component);
     }
 
     return error;