Messages in this thread | | | Date | Thu, 28 Feb 2019 16:25:01 +0100 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH AUTOSEL 4.20 34/81] debugfs: return error values, not NULL |
| |
On Thu, Feb 28, 2019 at 10:07:26AM -0500, Sasha Levin wrote: > From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > [ Upstream commit ff9fb72bc07705c00795ca48631f7fffe24d2c6b ] > > When an error happens, debugfs should return an error pointer value, not > NULL. This will prevent the totally theoretical error where a debugfs > call fails due to lack of memory, returning NULL, and that dentry value > is then passed to another debugfs call, which would end up succeeding, > creating a file at the root of the debugfs tree, but would then be > impossible to remove (because you can not remove the directory NULL). > > So, to make everyone happy, always return errors, this makes the users > of debugfs much simpler (they do not have to ever check the return > value), and everyone can rest easy. > > Reported-by: Gary R Hook <ghook@amd.com> > Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> > Reported-by: Masami Hiramatsu <mhiramat@kernel.org> > Reported-by: Michal Hocko <mhocko@kernel.org> > Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > Reported-by: Ulf Hansson <ulf.hansson@linaro.org> > Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> > Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Signed-off-by: Sasha Levin <sashal@kernel.org> > --- > fs/debugfs/inode.c | 39 ++++++++++++++++++++++----------------- > 1 file changed, 22 insertions(+), 17 deletions(-)
As much as I would love to backport this patch, no, please do not, I did not mark it for stable on purpose. It can cause regressions with code that is not expecting this behavior (I have a fix that needs to go into 5.0 for this very reason.)
Please drop it from all queues.
thanks,
greg k-h
| |