i386: Disallow kprobes on NMI handlers - try #2
PATCH 2/2 i386: Disallow kprobes on NMI handlers - try #2
A kprobe executes IRET early and that could cause NMI recursion and stack corruption.
Note: This problem was originally spotted by Andi Kleen. This patch
adds fixes not included in his original patch.
Signed-off-by Fernando Vazquez <[email protected]>
---
arch/i386/kernel/mca.c +5 -3
@@ -42,6 +42,7 @@#include <linux/errno.h> #include <linux/kernel.h> #include <linux/mca.h> +#include <linux/kprobes.h> #include <asm/system.h> #include <asm/io.h> #include <linux/proc_fs.h>
@@ -414,7 +415,8 @@ subsys_initcall(mca_init);/*--------------------------------------------------------------------*/ -static void mca_handle_nmi_device (struct mca_device *mca_dev,int check_flag) +static __kprobes void +mca_handle_nmi_device (struct mca_device *mca_dev,int check_flag) {int slot = mca_dev->slot;
@@ -444,7 +446,7 @@ static void mca_handle_nmi_device(struct/*--------------------------------------------------------------------*/ -static int mca_handle_nmi_callback (struct device *dev,void *data) +static int __kprobes mca_handle_nmi_callback (struct device *dev,void *data) {struct mca_device *mca_dev =to_mca_device (dev);unsigned char pos5;
@@ -462,7 +464,7 @@ static int mca_handle_nmi_callback(strucreturn 0 ; } -void mca_handle_nmi (void ) +void __kprobes mca_handle_nmi (void ) {/* First try - scan the various adapters and see if a specific * adapter was responsible for the error.