diff options
Diffstat (limited to 'arch/x86/kernel/kprobes')
-rw-r--r-- | arch/x86/kernel/kprobes/core.c | 108 | ||||
-rw-r--r-- | arch/x86/kernel/kprobes/opt.c | 4 |
2 files changed, 6 insertions, 106 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 2ca10b770cff..db8f8693ab8d 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -767,123 +767,21 @@ asm( NOKPROBE_SYMBOL(kretprobe_trampoline); STACK_FRAME_NON_STANDARD(kretprobe_trampoline); + /* * Called from kretprobe_trampoline */ __used __visible void *trampoline_handler(struct pt_regs *regs) { - struct kretprobe_instance *ri = NULL; - struct hlist_head *head, empty_rp; - struct hlist_node *tmp; - unsigned long flags, orig_ret_address = 0; - unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline; - kprobe_opcode_t *correct_ret_addr = NULL; - void *frame_pointer; - bool skipped = false; - - /* - * Set a dummy kprobe for avoiding kretprobe recursion. - * Since kretprobe never run in kprobe handler, kprobe must not - * be running at this point. - */ - kprobe_busy_begin(); - - INIT_HLIST_HEAD(&empty_rp); - kretprobe_hash_lock(current, &head, &flags); /* fixup registers */ regs->cs = __KERNEL_CS; #ifdef CONFIG_X86_32 regs->gs = 0; #endif - /* We use pt_regs->sp for return address holder. */ - frame_pointer = ®s->sp; - regs->ip = trampoline_address; + regs->ip = (unsigned long)&kretprobe_trampoline; regs->orig_ax = ~0UL; - /* - * It is possible to have multiple instances associated with a given - * task either because multiple functions in the call path have - * return probes installed on them, and/or more than one - * return probe was registered for a target function. - * - * We can handle this because: - * - instances are always pushed into the head of the list - * - when multiple return probes are registered for the same - * function, the (chronologically) first instance's ret_addr - * will be the real return address, and all the rest will - * point to kretprobe_trampoline. - */ - hlist_for_each_entry(ri, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - /* - * Return probes must be pushed on this hash list correct - * order (same as return order) so that it can be popped - * correctly. However, if we find it is pushed it incorrect - * order, this means we find a function which should not be - * probed, because the wrong order entry is pushed on the - * path of processing other kretprobe itself. - */ - if (ri->fp != frame_pointer) { - if (!skipped) - pr_warn("kretprobe is stacked incorrectly. Trying to fixup.\n"); - skipped = true; - continue; - } - - orig_ret_address = (unsigned long)ri->ret_addr; - if (skipped) - pr_warn("%ps must be blacklisted because of incorrect kretprobe order\n", - ri->rp->kp.addr); - - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - - kretprobe_assert(ri, orig_ret_address, trampoline_address); - - correct_ret_addr = ri->ret_addr; - hlist_for_each_entry_safe(ri, tmp, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - if (ri->fp != frame_pointer) - continue; - - orig_ret_address = (unsigned long)ri->ret_addr; - if (ri->rp && ri->rp->handler) { - __this_cpu_write(current_kprobe, &ri->rp->kp); - ri->ret_addr = correct_ret_addr; - ri->rp->handler(ri, regs); - __this_cpu_write(current_kprobe, &kprobe_busy); - } - - recycle_rp_inst(ri, &empty_rp); - - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - - kretprobe_hash_unlock(current, &flags); - - kprobe_busy_end(); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } - return (void *)orig_ret_address; + return (void *)kretprobe_trampoline_handler(regs, &kretprobe_trampoline, ®s->sp); } NOKPROBE_SYMBOL(trampoline_handler); diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index b8dd113a1284..15e06408f6ba 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -18,6 +18,7 @@ #include <linux/ftrace.h> #include <linux/frame.h> #include <linux/pgtable.h> +#include <linux/static_call.h> #include <asm/text-patching.h> #include <asm/cacheflush.h> @@ -209,7 +210,8 @@ static int copy_optimized_instructions(u8 *dest, u8 *src, u8 *real) /* Check whether the address range is reserved */ if (ftrace_text_reserved(src, src + len - 1) || alternatives_text_reserved(src, src + len - 1) || - jump_label_text_reserved(src, src + len - 1)) + jump_label_text_reserved(src, src + len - 1) || + static_call_text_reserved(src, src + len - 1)) return -EBUSY; return len; |