2.6.24-stable review patch. If anyone has any objections, please let us know.
------------------ From: Sam Ravnborg <[EMAIL PROTECTED]> commit: e06b8b98da071f7dd78fb7822991694288047df0 Arjan van de Ven <[EMAIL PROTECTED]> wrote: === I just read the excellent LWN writeup of the vmsplice security thing, and that got me wondering why this attack wasn't stopped by the CONFIG_CC_STACKPROTECTOR option... because it plain should have been... Some analysis later.. it turns out that the following line in the top level Makefile, added by you in October 2007, entirely disables CONFIG_CC_STACKPROTECTOR ;( With this line removed the exploit will be nicely stopped. CFLAGS += $(call cc-option, -fno-stack-protector) Now I realize that certain distros have patched gcc to compensate for their lack of distro wide CFLAGS, and it's great to work around that... but would there be a way to NOT disable this for CONFIG_CC_STACKPROTECTOR please? It would have made this exploit not possible for those kernels that enable this feature (and that includes distros like Fedora) === Move the assignment to KBUILD_CFLAGS up before including the arch specific Makefile so arch makefiles may override the setting. Signed-off-by: Sam Ravnborg <[EMAIL PROTECTED]> Cc: Arjan van de Ven <[EMAIL PROTECTED]> Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]> --- Makefile | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/Makefile +++ b/Makefile @@ -507,6 +507,10 @@ else KBUILD_CFLAGS += -O2 endif +# Force gcc to behave correct even for buggy distributions +# Arch Makefiles may override this setting +KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector) + include $(srctree)/arch/$(SRCARCH)/Makefile ifdef CONFIG_FRAME_POINTER @@ -520,9 +524,6 @@ KBUILD_CFLAGS += -g KBUILD_AFLAGS += -gdwarf-2 endif -# Force gcc to behave correct even for buggy distributions -KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector) - # arch Makefile may override CC so keep this after arch Makefile is included NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include) CHECKFLAGS += $(NOSTDINC_FLAGS) -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
