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.
v3:
- fixed indentation
- selftests: use ASSERT_EQ instead of EXPECT_EQ for hard failures
v2: https://lkml.kernel.org/lkml/[email protected]/
- 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).
v1: https://lkml.kernel.org/lkml/[email protected]/
Giuseppe Scrivano (2):
fs, close_range: add flag CLOSE_RANGE_CLOEXEC
selftests: core: 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(-)
--
2.28.0
On Wed, Nov 18, 2020 at 11:47:44AM +0100, Giuseppe Scrivano wrote:
> 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.
>
> v3:
> - fixed indentation
> - selftests: use ASSERT_EQ instead of EXPECT_EQ for hard failures
>
> v2: https://lkml.kernel.org/lkml/[email protected]/
> - 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).
>
> v1: https://lkml.kernel.org/lkml/[email protected]/
>
> Giuseppe Scrivano (2):
> fs, close_range: add flag CLOSE_RANGE_CLOEXEC
> selftests: core: 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(-)
I've picked this up and stuffed it into -next. This solves a real
problem and I don't want it to sit around another merge window. (If you
pick it up later I'll simply drop it, Al.)
Christian