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authorNamhyung Kim <namhyung.kim@lge.com>2013-11-26 15:21:04 +0900
committerSteven Rostedt <rostedt@goodmis.org>2014-01-02 16:17:43 -0500
commit5baaa59ef09e8729aef101f7bf7d9d0af00852e3 (patch)
treeadf05e51e33e06d0d9eb9689269364314b754c2c /kernel/trace/trace_uprobe.c
parent3925f4a5afa489e905a08edffc36a435a3434a63 (diff)
tracing/probes: Implement 'memory' fetch method for uprobes
Use separate method to fetch from memory. Move existing functions to trace_kprobe.c and make them static. Also add new memory fetch implementation for uprobes. Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'kernel/trace/trace_uprobe.c')
-rw-r--r--kernel/trace/trace_uprobe.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 24ef6a33d93f..bebd2f5d9ea3 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -114,6 +114,58 @@ DEFINE_BASIC_FETCH_FUNCS(stack)
#define fetch_stack_string NULL
#define fetch_stack_string_size NULL
+#define DEFINE_FETCH_memory(type) \
+static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
+ void *addr, void *dest) \
+{ \
+ type retval; \
+ void __user *vaddr = (void __force __user *) addr; \
+ \
+ if (copy_from_user(&retval, vaddr, sizeof(type))) \
+ *(type *)dest = 0; \
+ else \
+ *(type *) dest = retval; \
+}
+DEFINE_BASIC_FETCH_FUNCS(memory)
+/*
+ * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
+ * length and relative data location.
+ */
+static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
+ void *addr, void *dest)
+{
+ long ret;
+ u32 rloc = *(u32 *)dest;
+ int maxlen = get_rloc_len(rloc);
+ u8 *dst = get_rloc_data(dest);
+ void __user *src = (void __force __user *) addr;
+
+ if (!maxlen)
+ return;
+
+ ret = strncpy_from_user(dst, src, maxlen);
+
+ if (ret < 0) { /* Failed to fetch string */
+ ((u8 *)get_rloc_data(dest))[0] = '\0';
+ *(u32 *)dest = make_data_rloc(0, get_rloc_offs(rloc));
+ } else {
+ *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(rloc));
+ }
+}
+
+static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
+ void *addr, void *dest)
+{
+ int len;
+ void __user *vaddr = (void __force __user *) addr;
+
+ len = strnlen_user(vaddr, MAX_STRING_SIZE);
+
+ if (len == 0 || len > MAX_STRING_SIZE) /* Failed to check length */
+ *(u32 *)dest = 0;
+ else
+ *(u32 *)dest = len;
+}
/* uprobes do not support symbol fetch methods */
#define fetch_symbol_u8 NULL