[PATCH 2/3] proc: Update get proc_pid_cmdline() to use mm.h helpers
Re-factor proc_pid_cmdline() to use get_cmdline_length() and
copy_cmdline() helpers from mm.h
Signed-off-by: William Roberts <wroberts(a)tresys.com>
---
fs/proc/base.c | 35 ++++++++++-------------------------
1 file changed, 10 insertions(+), 25 deletions(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 03c8d74..fb4eda5 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -203,37 +203,22 @@ static int proc_root_link(struct dentry *dentry, struct path *path)
static int proc_pid_cmdline(struct task_struct *task, char * buffer)
{
int res = 0;
- unsigned int len;
+ unsigned int len = 0;
struct mm_struct *mm = get_task_mm(task);
if (!mm)
- goto out;
- if (!mm->arg_end)
- goto out_mm; /* Shh! No looking before we're done */
+ return 0;
- len = mm->arg_end - mm->arg_start;
-
+ len = get_cmdline_length(mm);
+ if (!len)
+ goto mm_out;
+
+ /*The caller of this allocates a page */
if (len > PAGE_SIZE)
len = PAGE_SIZE;
-
- res = access_process_vm(task, mm->arg_start, buffer, len, 0);
-
- // If the nul at the end of args has been overwritten, then
- // assume application is using setproctitle(3).
- if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE)
{
- len = strnlen(buffer, res);
- if (len < res) {
- res = len;
- } else {
- len = mm->env_end - mm->env_start;
- if (len > PAGE_SIZE - res)
- len = PAGE_SIZE - res;
- res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
- res = strnlen(buffer, res);
- }
- }
-out_mm:
+
+ res = copy_cmdline(task, mm, buffer, len);
+mm_out:
mmput(mm);
-out:
return res;
}
--
1.7.9.5