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authorDavid S. Miller <davem@davemloft.net>2010-04-11 14:53:53 -0700
committerDavid S. Miller <davem@davemloft.net>2010-04-11 14:53:53 -0700
commit871039f02f8ec4ab2e5e9010718caa8e085786f1 (patch)
treef0d2b3127fc48c862967d68c46c2d46668137515 /arch/arm/kernel/kprobes.c
parente4077e018b5ead3de9951fc01d8bf12eeeeeefed (diff)
parent4a1032faac94ebbf647460ae3e06fc21146eb280 (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts: drivers/net/stmmac/stmmac_main.c drivers/net/wireless/wl12xx/wl1271_cmd.c drivers/net/wireless/wl12xx/wl1271_main.c drivers/net/wireless/wl12xx/wl1271_spi.c net/core/ethtool.c net/mac80211/scan.c
Diffstat (limited to 'arch/arm/kernel/kprobes.c')
-rw-r--r--arch/arm/kernel/kprobes.c11
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c
index 60c62c377fa9..2ba7deb3072e 100644
--- a/arch/arm/kernel/kprobes.c
+++ b/arch/arm/kernel/kprobes.c
@@ -22,6 +22,7 @@
#include <linux/kernel.h>
#include <linux/kprobes.h>
#include <linux/module.h>
+#include <linux/slab.h>
#include <linux/stop_machine.h>
#include <linux/stringify.h>
#include <asm/traps.h>
@@ -393,6 +394,14 @@ void __kprobes jprobe_return(void)
/*
* Setup an empty pt_regs. Fill SP and PC fields as
* they're needed by longjmp_break_handler.
+ *
+ * We allocate some slack between the original SP and start of
+ * our fabricated regs. To be precise we want to have worst case
+ * covered which is STMFD with all 16 regs so we allocate 2 *
+ * sizeof(struct_pt_regs)).
+ *
+ * This is to prevent any simulated instruction from writing
+ * over the regs when they are accessing the stack.
*/
"sub sp, %0, %1 \n\t"
"ldr r0, ="__stringify(JPROBE_MAGIC_ADDR)"\n\t"
@@ -410,7 +419,7 @@ void __kprobes jprobe_return(void)
"ldmia sp, {r0 - pc} \n\t"
:
: "r" (kcb->jprobe_saved_regs.ARM_sp),
- "I" (sizeof(struct pt_regs)),
+ "I" (sizeof(struct pt_regs) * 2),
"J" (offsetof(struct pt_regs, ARM_sp)),
"J" (offsetof(struct pt_regs, ARM_pc)),
"J" (offsetof(struct pt_regs, ARM_cpsr))