[PATCH v2 0/2] fs, close_range: add flag CLOSE_RANGE_CLOEXEC

[Giuseppe Scrivano <gscrivan@redhat.com>]

When the new flag is used, close_range will set the close-on-exec bit
for the file descriptors instead of close()-ing them.

It is useful for e.g. container runtimes that want to minimize the
number of syscalls used after a seccomp profile is installed but want
to keep some fds open until the container process is executed.

v1->v2:
* move close_range(..., CLOSE_RANGE_CLOEXEC) implementation to a separate function.
* use bitmap_set() to set the close-on-exec bits in the bitmap.
* add test with rlimit(RLIMIT_NOFILE) in place.
* use "cur_max" that is already used by close_range(..., 0).

Giuseppe Scrivano (2):
  fs, close_range: add flag CLOSE_RANGE_CLOEXEC
  selftests: add tests for CLOSE_RANGE_CLOEXEC

 fs/file.c                                     | 44 ++++++++---
 include/uapi/linux/close_range.h              |  3 +
 .../testing/selftests/core/close_range_test.c | 74 +++++++++++++++++++
 3 files changed, 111 insertions(+), 10 deletions(-)

--
2.26.2