Re: [PATCH] setfiles: Add -A option to disable SELINUX_RESTORECON_ADD_ASSOC

[Petr Lautrbach <lautrbach@redhat.com>]

Stephen Smalley <stephen.smalley.work@gmail.com> writes:

> On Mon, Sep 1, 2025 at 10:34 AM Richard W.M. Jones <rjones@redhat.com> wrote:
>>
>> SELINUX_RESTORECON_ADD_ASSOC tracks conflicts between inodes that have
>> differing contexts.  However doing this involves building a large
>> internal hashtable that stores the full path of every file examined by
>> setfiles.  For filesystems that have very large numbers of files or
>> long pathnames, this uses a lot of memory, which makes SELinux
>> relabelling in constrained memory environments infeasible.
>>
>> This adds a new setfiles -A option that disables this tracking.
>>
>> For example, using setfiles to relabel a filesystem with 15 million
>> files took 3.7GB of RAM.  Using this option, the same filesystem can
>> be relabelled in 121MB (albeit with no warnings or errors possible for
>> conflicting labels, but for our use case we don't care about that.)
>>
>> Fixes: https://issues.redhat.com/browse/RHEL-111505
>> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
>
> I don't think we usually include downstream issue tracker links in our
> upstream commit messages, but no need to re-submit just for that.

FTR in git log there are already about 60 references to bugzilla.redhat.com and
issues.redhat.com is replacement of bugzilla.redhat.com for issues
reported on RHEL or CentOS. There are also bugs.debian.org,
bugs.gentoo.org, bugs.chromium.org references.


Until these issue trackers disappear, it could be a good source for another
context or related discussions.

> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
>
>> ---
>>  policycoreutils/setfiles/setfiles.8 | 4 ++++
>>  policycoreutils/setfiles/setfiles.c | 5 ++++-
>>  2 files changed, 8 insertions(+), 1 deletion(-)
>>
>> diff --git a/policycoreutils/setfiles/setfiles.8 b/policycoreutils/setfiles/setfiles.8
>> index eabf0a1c..7c9c5d39 100644
>> --- a/policycoreutils/setfiles/setfiles.8
>> +++ b/policycoreutils/setfiles/setfiles.8
>> @@ -23,6 +23,7 @@ setfiles \- set SELinux file security contexts.
>>  .RB [ \-I | \-D ]
>>  .RB [ \-T
>>  .IR nthreads ]
>> +.RB [ \-A ]
>>  .I spec_file
>>  .IR pathname \ ...
>>
>> @@ -187,6 +188,9 @@ use up to
>>  threads.  Specify 0 to create as many threads as there are available
>>  CPU cores; 1 to use only a single thread (default); or any positive
>>  number to use the given number of threads (if possible).
>> +.TP
>> +.B \-A
>> +do not track conflicting inodes (saves memory)
>>
>>  .SH "ARGUMENTS"
>>  .TP
>> diff --git a/policycoreutils/setfiles/setfiles.c b/policycoreutils/setfiles/setfiles.c
>> index ad09f840..40f2e7fe 100644
>> --- a/policycoreutils/setfiles/setfiles.c
>> +++ b/policycoreutils/setfiles/setfiles.c
>> @@ -147,7 +147,7 @@ int main(int argc, char **argv)
>>         const char *base;
>>         int errors = 0;
>>         const char *ropts = "e:f:hiIDlmno:pqrsvFURW0xT:";
>> -       const char *sopts = "c:de:f:hiIDlmno:pqr:svCEFUR:W0T:";
>> +       const char *sopts = "c:de:f:hiIDlmno:pqr:svCEFUR:W0T:A";
>>         const char *opts;
>>         union selinux_callback cb;
>>         long unsigned skipped_errors;
>> @@ -375,6 +375,9 @@ int main(int argc, char **argv)
>>                         if (*optarg == '\0' || *endptr != '\0')
>>                                 usage(argv[0]);
>>                         break;
>> +               case 'A':
>> +                       r_opts.add_assoc = 0;
>> +                       break;
>>                 case 'h':
>>                 case '?':
>>                         usage(argv[0]);
>> --
>> 2.50.1
>>
>>