From: Dan Li ashimida@linux.alibaba.com
[ Upstream commit 9fcb2e93f41c07a400885325e7dbdfceba6efaec ]
__stack_chk_guard is setup once while init stage and never changed after that.
Although the modification of this variable at runtime will usually cause the kernel to crash (so does the attacker), it should be marked as __ro_after_init, and it should not affect performance if it is placed in the ro_after_init section.
Signed-off-by: Dan Li ashimida@linux.alibaba.com Acked-by: Mark Rutland mark.rutland@arm.com Link: https://lore.kernel.org/r/1631612642-102881-1-git-send-email-ashimida@linux.... Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/kernel/process.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index c8989b999250..c858b857c1ec 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -60,7 +60,7 @@
#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_STACKPROTECTOR_PER_TASK) #include <linux/stackprotector.h> -unsigned long __stack_chk_guard __read_mostly; +unsigned long __stack_chk_guard __ro_after_init; EXPORT_SYMBOL(__stack_chk_guard); #endif