scripts: gdb: vfs: support external dentry names

d_shortname of struct dentry only reserves D_NAME_INLINE_LEN characters
and contains garbage for longer names. Use d_name instead, which always
references the valid name.

Link: https://lore.kernel.org/all/[e-mail]/
Link: https://lkml.kernel.org/r/[e-mail]
Fixes: 79300ac805b6 ("scripts/gdb: fix dentry_name() lookup")
Signed-off-by: Illia Ostapyshyn <[e-mail]>
Tested-by: Florian Fainelli <[e-mail]>
Reviewed-by: Florian Fainelli <[e-mail]>
Cc: Al Viro <[e-mail]>
Cc: Christian Brauner <[e-mail]>
Cc: Jan Kara <[e-mail]>
Cc: Jan Kiszka <[e-mail]>
Cc: Kieran Bingham <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

scripts/gdb/linux/vfs.py

···
     if parent == d or parent == 0:
         return ""
     p = dentry_name(d['d_parent']) + "/"
-    return p + d['d_shortname']['string'].string()
+    return p + d['d_name']['name'].string()
 
 class DentryName(gdb.Function):
     """Return string of the full path of a dentry.