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kprobes: treewide: Use 'kprobe_opcode_t *' for the code address in get_optimized_kprobe()

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Since get_optimized_kprobe() is only used inside kprobes,
it doesn't need to use 'unsigned long' type for 'addr' parameter.
Make it use 'kprobe_opcode_t *' for the 'addr' parameter and
subsequent call of arch_within_optimized_kprobe() also should use
'kprobe_opcode_t *'.

Note that MAX_OPTIMIZED_LENGTH and RELATIVEJUMP_SIZE are defined
by byte-size, but the size of 'kprobe_opcode_t' depends on the
architecture. Therefore, we must be careful when calculating
addresses using those macros.

Link: https://lkml.kernel.org/r/163163040680.489837.12133032364499833736.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Masami Hiramatsu 2021-09-14 23:40:07 +09:00 committed by Steven Rostedt (VMware)
parent 57d4e31780
commit c42421e205
5 changed files with 16 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
arch/arm/probes/kprobes/opt-arm.c
View File

@ -347,10 +347,11 @@ void arch_unoptimize_kprobes(struct list_head *oplist,
}
int arch_within_optimized_kprobe(struct optimized_kprobe *op,
unsigned long addr)
kprobe_opcode_t *addr)
{
return ((unsigned long)op->kp.addr <= addr &&
(unsigned long)op->kp.addr + RELATIVEJUMP_SIZE > addr);
return (op->kp.addr <= addr &&
op->kp.addr + (RELATIVEJUMP_SIZE / sizeof(kprobe_opcode_t)) > addr);
}
void arch_remove_optimized_kprobe(struct optimized_kprobe *op)

6
arch/powerpc/kernel/optprobes.c
View File

@ -301,8 +301,8 @@ void arch_unoptimize_kprobes(struct list_head *oplist, struct list_head *done_li
}
}
int arch_within_optimized_kprobe(struct optimized_kprobe *op, unsigned long addr)
int arch_within_optimized_kprobe(struct optimized_kprobe *op, kprobe_opcode_t *addr)
{
return ((unsigned long)op->kp.addr <= addr &&
(unsigned long)op->kp.addr + RELATIVEJUMP_SIZE > addr);
return (op->kp.addr <= addr &&
op->kp.addr + (RELATIVEJUMP_SIZE / sizeof(kprobe_opcode_t)) > addr);
}

6
arch/x86/kernel/kprobes/opt.c
View File

@ -367,10 +367,10 @@ int arch_check_optimized_kprobe(struct optimized_kprobe *op)
/* Check the addr is within the optimized instructions. */
int arch_within_optimized_kprobe(struct optimized_kprobe *op,
unsigned long addr)
kprobe_opcode_t *addr)
{
return ((unsigned long)op->kp.addr <= addr &&
(unsigned long)op->kp.addr + op->optinsn.size > addr);
return (op->kp.addr <= addr &&
op->kp.addr + op->optinsn.size > addr);
}
/* Free optimized instruction slot */

2
include/linux/kprobes.h
View File

@ -329,7 +329,7 @@ extern void arch_unoptimize_kprobes(struct list_head *oplist,
struct list_head *done_list);
extern void arch_unoptimize_kprobe(struct optimized_kprobe *op);
extern int arch_within_optimized_kprobe(struct optimized_kprobe *op,
unsigned long addr);
kprobe_opcode_t *addr);
extern void opt_pre_handler(struct kprobe *p, struct pt_regs *regs);

10
kernel/kprobes.c
View File

@ -485,15 +485,15 @@ static int kprobe_queued(struct kprobe *p)
* Return an optimized kprobe whose optimizing code replaces
* instructions including 'addr' (exclude breakpoint).
*/
static struct kprobe *get_optimized_kprobe(unsigned long addr)
static struct kprobe *get_optimized_kprobe(kprobe_opcode_t *addr)
{
int i;
struct kprobe *p = NULL;
struct optimized_kprobe *op;
/* Don't check i == 0, since that is a breakpoint case. */
for (i = 1; !p && i < MAX_OPTIMIZED_LENGTH; i++)
p = get_kprobe((void *)(addr - i));
for (i = 1; !p && i < MAX_OPTIMIZED_LENGTH / sizeof(kprobe_opcode_t); i++)
p = get_kprobe(addr - i);
if (p && kprobe_optready(p)) {
op = container_of(p, struct optimized_kprobe, kp);
@ -967,7 +967,7 @@ static void __arm_kprobe(struct kprobe *p)
lockdep_assert_held(&text_mutex);
/* Find the overlapping optimized kprobes. */
_p = get_optimized_kprobe((unsigned long)p->addr);
_p = get_optimized_kprobe(p->addr);
if (unlikely(_p))
/* Fallback to unoptimized kprobe */
unoptimize_kprobe(_p, true);
@ -989,7 +989,7 @@ static void __disarm_kprobe(struct kprobe *p, bool reopt)
if (!kprobe_queued(p)) {
arch_disarm_kprobe(p);
/* If another kprobe was blocked, re-optimize it. */
_p = get_optimized_kprobe((unsigned long)p->addr);
_p = get_optimized_kprobe(p->addr);
if (unlikely(_p) && reopt)
optimize_kprobe(_p);
}