search for: env_prefix_len

...<keyutils.h> #include <time.h> @@ -154,11 +155,126 @@ err_cache: return credtime; } +#define ENV_PATH_FMT "/proc/%d/environ" +#define ENV_PATH_MAXLEN (6 + 10 + 8 + 1) + +#define ENV_NAME "KRB5CCNAME" +#define ENV_PREFIX "KRB5CCNAME=" +#define ENV_PREFIX_LEN 11 + +#define ENV_BUF_START (4096) +#define ENV_BUF_MAX (131072) + +/** + * get_cachename_from_process_env - scrape value of $KRB5CCNAME out of the + * initiating process' environment. + * @pid: initiating pid value from the upcall string + * + * Open the /proc/<pid>/environ...

Third respin of this series. Reordered for better safety for bisecting. The environment scraping is now on by default, but can be disabled with "-E" in environments where it's not needed. Also, I've added a patch to make cifs.upcall drop capabilities before doing most of its work. This may help reduce the attack surface of the program. Jeff Layton (4): cifs.upcall: convert

...#include <time.h> @@ -154,12 +155,127 @@ err_cache: return credtime; } +#define CIFS_UPCALL_ENV_PATH_FMT "/proc/%d/environ" +#define CIFS_UPCALL_ENV_PATH_MAXLEN (6 + 10 + 8 + 1) + +#define ENV_NAME "KRB5CCNAME" +#define ENV_PREFIX "KRB5CCNAME=" +#define ENV_PREFIX_LEN 11 + +#define ENV_BUF_START (4096) +#define ENV_BUF_MAX (131072) + +/** + * get_cachename_from_process_env - scrape value of $KRB5CCNAME out of the + * initiating process' environment. + * @pid: initiating pid value from the upcall string + * + * Open the /proc/<pid>/environ...

Small respin of the patches that I posted a few days ago. The main difference is the reordering of the series to make it do the group and grouplist manipulation first, and then the patch that makes it grab the KRB5CCNAME from the initiating process. I think the code is sound, my main question is whether we really need the command-line switch for this. Should this just be the default mode of

Apologies for v3 series, I had some extra patches in there. This is the one that should have been sent. Relabeled as v4 for clarity. Third respin of this series. Reordered for better safety for bisecting. The environment scraping is now on by default, but can be disabled with "-E" in environments where it's not needed. Also, I've added a patch to make cifs.upcall drop

On Fri, 2017-02-10 at 11:15 -0600, Chad William Seys wrote: > Hi Jeff, > > > So we have a default credcache for the user for whom we are operating > > as, but we can't get the default principal name from it. My guess is > > that it's not finding the > > This mount is run by root UID=0 and seems to be find that credential > cache without problem (earlier