From f1d3cbfaafc10464550c6d3a125f4fc802bbaed5 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Wed, 12 Oct 2022 06:40:56 -0400 Subject: tracing: Move duplicate code of trace_kprobe/eprobe.c into header The functions: fetch_store_strlen_user() fetch_store_strlen() fetch_store_string_user() fetch_store_string() are identical in both trace_kprobe.c and trace_eprobe.c. Move them into a new header file trace_probe_kernel.h to share it. This code will later be used by the synthetic events as well. Marked for stable as a fix for a crash in synthetic events requires it. Link: https://lkml.kernel.org/r/20221012104534.467668078@goodmis.org Cc: stable@vger.kernel.org Cc: Andrew Morton Cc: Tom Zanussi Acked-by: Masami Hiramatsu (Google) Reviewed-by: Tom Zanussi Fixes: bd82631d7ccdc ("tracing: Add support for dynamic strings to synthetic events") Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_kprobe.c | 60 ++++----------------------------------------- 1 file changed, 5 insertions(+), 55 deletions(-) (limited to 'kernel/trace/trace_kprobe.c') diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 23f7f0ec4f4c..5a75b039e586 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -20,6 +20,7 @@ #include "trace_kprobe_selftest.h" #include "trace_probe.h" #include "trace_probe_tmpl.h" +#include "trace_probe_kernel.h" #define KPROBE_EVENT_SYSTEM "kprobes" #define KRETPROBE_MAXACTIVE_MAX 4096 @@ -1223,29 +1224,14 @@ static const struct file_operations kprobe_profile_ops = { static nokprobe_inline int fetch_store_strlen_user(unsigned long addr) { - const void __user *uaddr = (__force const void __user *)addr; - - return strnlen_user_nofault(uaddr, MAX_STRING_SIZE); + return kern_fetch_store_strlen_user(addr); } /* Return the length of string -- including null terminal byte */ static nokprobe_inline int fetch_store_strlen(unsigned long addr) { - int ret, len = 0; - u8 c; - -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - if (addr < TASK_SIZE) - return fetch_store_strlen_user(addr); -#endif - - do { - ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1); - len++; - } while (c && ret == 0 && len < MAX_STRING_SIZE); - - return (ret < 0) ? ret : len; + return kern_fetch_store_strlen(addr); } /* @@ -1255,21 +1241,7 @@ fetch_store_strlen(unsigned long addr) static nokprobe_inline int fetch_store_string_user(unsigned long addr, void *dest, void *base) { - const void __user *uaddr = (__force const void __user *)addr; - int maxlen = get_loc_len(*(u32 *)dest); - void *__dest; - long ret; - - if (unlikely(!maxlen)) - return -ENOMEM; - - __dest = get_loc_data(dest, base); - - ret = strncpy_from_user_nofault(__dest, uaddr, maxlen); - if (ret >= 0) - *(u32 *)dest = make_data_loc(ret, __dest - base); - - return ret; + return kern_fetch_store_string_user(addr, dest, base); } /* @@ -1279,29 +1251,7 @@ fetch_store_string_user(unsigned long addr, void *dest, void *base) static nokprobe_inline int fetch_store_string(unsigned long addr, void *dest, void *base) { - int maxlen = get_loc_len(*(u32 *)dest); - void *__dest; - long ret; - -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - if ((unsigned long)addr < TASK_SIZE) - return fetch_store_string_user(addr, dest, base); -#endif - - if (unlikely(!maxlen)) - return -ENOMEM; - - __dest = get_loc_data(dest, base); - - /* - * Try to get string again, since the string can be changed while - * probing. - */ - ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen); - if (ret >= 0) - *(u32 *)dest = make_data_loc(ret, __dest - base); - - return ret; + return kern_fetch_store_string(addr, dest, base); } static nokprobe_inline int -- cgit v1.2.3-58-ga151