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IIO uses anon_inode_get() to allocate file descriptors as part of its ioctls. But those ioctls are lacking a flag argument allowing userspace to choose options for the newly opened file descriptor. In such case it's advised to use O_CLOEXEC by default so that userspace is allowed to choose, without race, if the file descriptor is going to be inherited across exec(). KVM usage of anon_inode_getfd() was fixed in a previous patchset [1], so IIO is the only subsystem using anon_inode_getfd() with a fixed set of flags not including O_CLOEXEC. This patch set O_CLOEXEC flag on the event file descriptor created with anon_inode_getfd() to not leak file descriptors across exec(). Links: - Secure File Descriptor Handling (Ulrich Drepper, 2008) http://udrepper.livejournal.com/20407.html - Excuse me son, but your code is leaking !!! (Dan Walsh, March 2012) http://danwalsh.livejournal.com/53603.html - [1] kvm: use anon_inode_getfd() with O_CLOEXEC flag http://lkml.kernel.org/r/cover.1377372576.git.ydroneaud@opteya.com Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>