diff options
| -rw-r--r-- | include/linux/uprobes.h | 3 | ||||
| -rw-r--r-- | kernel/events/uprobes.c | 11 |
2 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index b0507f24eeb0..06f28beed7c2 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -38,6 +38,8 @@ struct inode; #define UPROBE_HANDLER_REMOVE 1 #define UPROBE_HANDLER_MASK 1 +#define MAX_URETPROBE_DEPTH 64 + enum uprobe_filter_ctx { UPROBE_FILTER_REGISTER, UPROBE_FILTER_UNREGISTER, @@ -72,6 +74,7 @@ struct uprobe_task { struct arch_uprobe_task autask; struct return_instance *return_instances; + unsigned int depth; struct uprobe *active_uprobe; unsigned long xol_vaddr; diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 65429ad2ce51..6ab00e090c87 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1404,6 +1404,13 @@ static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs) if (!utask) return; + if (utask->depth >= MAX_URETPROBE_DEPTH) { + printk_ratelimited(KERN_INFO "uprobe: omit uretprobe due to" + " nestedness limit pid/tgid=%d/%d\n", + current->pid, current->tgid); + return; + } + ri = kzalloc(sizeof(struct return_instance), GFP_KERNEL); if (!ri) goto fail; @@ -1439,6 +1446,8 @@ static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs) ri->orig_ret_vaddr = orig_ret_vaddr; ri->chained = chained; + utask->depth++; + /* add instance to the stack */ ri->next = utask->return_instances; utask->return_instances = ri; @@ -1681,6 +1690,8 @@ static bool handle_trampoline(struct pt_regs *regs) if (!chained) break; + utask->depth--; + BUG_ON(!ri); } |