From: Steven Rostedt (Google) rostedt@goodmis.org
commit a4412fdd49dc011bcc2c0d81ac4cab7457092650 upstream.
The config to be able to inject error codes into any function annotated with ALLOW_ERROR_INJECTION() is enabled when FUNCTION_ERROR_INJECTION is enabled. But unfortunately, this is always enabled on x86 when KPROBES is enabled, and there's no way to turn it off.
As kprobes is useful for observability of the kernel, it is useful to have it enabled in production environments. But error injection should be avoided. Add a prompt to the config to allow it to be disabled even when kprobes is enabled, and get rid of the "def_bool y".
This is a kernel debug feature (it's in Kconfig.debug), and should have never been something enabled by default.
Cc: stable@vger.kernel.org Fixes: 540adea3809f6 ("error-injection: Separate error-injection from kprobe") Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- lib/Kconfig.debug | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1510,8 +1510,14 @@ config NETDEV_NOTIFIER_ERROR_INJECT If unsure, say N.
config FUNCTION_ERROR_INJECTION - def_bool y + bool "Fault-injections of functions" depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES + help + Add fault injections into various functions that are annotated with + ALLOW_ERROR_INJECTION() in the kernel. BPF may also modify the return + value of theses functions. This is useful to test error paths of code. + + If unsure, say N
config FAULT_INJECTION bool "Fault-injection framework"