The patch titled
Don't truncate /proc/PID/environ at 4096 characters
has been added to the -mm tree. Its filename is
dont-truncate-proc-pid-environ-at-4096-characters.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: Don't truncate /proc/PID/environ at 4096 characters
From: "James Pearson" <james-p@xxxxxxxxxxxxxxxxxx>
/proc/PID/environ currently truncates at 4096 characters, patch based on
the /proc/PID/mem code.
Signed-off-by: James Pearson <james-p@xxxxxxxxxxxxxxxxxx>
Cc: Anton Arapov <aarapov@xxxxxxxxxx>
Cc: Jan Engelhardt <jengelh@xxxxxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Cc: Randy Dunlap <randy.dunlap@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
diff -puN fs/proc/base.c~dont-truncate-proc-pid-environ-at-4096-characters fs/proc/base.c
--- a/fs/proc/base.c~dont-truncate-proc-pid-environ-at-4096-characters
+++ a/fs/proc/base.c
@@ -199,27 +199,6 @@ static int proc_root_link(struct inode *
(task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
security_ptrace(current,task) == 0))
-static int proc_pid_environ(struct task_struct *task, char * buffer)
-{
- int res = 0;
- struct mm_struct *mm = get_task_mm(task);
- if (mm) {
- unsigned int len;
-
- res = -ESRCH;
- if (!ptrace_may_attach(task))
- goto out;
-
- len = mm->env_end - mm->env_start;
- if (len > PAGE_SIZE)
- len = PAGE_SIZE;
- res = access_process_vm(task, mm->env_start, buffer, len, 0);
-out:
- mmput(mm);
- }
- return res;
-}
-
static int proc_pid_cmdline(struct task_struct *task, char * buffer)
{
int res = 0;
@@ -658,6 +637,76 @@ static const struct file_operations proc
.open = mem_open,
};
+static ssize_t environ_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+ char *page;
+ unsigned long src = *ppos;
+ int ret = -ESRCH;
+ struct mm_struct *mm;
+
+ if (!task)
+ goto out_no_task;
+
+ if (!ptrace_may_attach(task))
+ goto out;
+
+ ret = -ENOMEM;
+ page = (char *)__get_free_page(GFP_TEMPORARY);
+ if (!page)
+ goto out;
+
+ ret = 0;
+
+ mm = get_task_mm(task);
+ if (!mm)
+ goto out_free;
+
+ while (count > 0) {
+ int this_len, retval, max_len;
+
+ this_len = mm->env_end - (mm->env_start + src);
+
+ if (this_len <= 0)
+ break;
+
+ max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
+ this_len = (this_len > max_len) ? max_len : this_len;
+
+ retval = access_process_vm(task, (mm->env_start + src),
+ page, this_len, 0);
+
+ if (retval <= 0) {
+ ret = retval;
+ break;
+ }
+
+ if (copy_to_user(buf, page, retval)) {
+ ret = -EFAULT;
+ break;
+ }
+
+ ret += retval;
+ src += retval;
+ buf += retval;
+ count -= retval;
+ }
+ *ppos = src;
+
+ mmput(mm);
+out_free:
+ free_page((unsigned long) page);
+out:
+ put_task_struct(task);
+out_no_task:
+ return ret;
+}
+
+static const struct file_operations proc_environ_operations = {
+ .read = environ_read,
+};
+
static ssize_t oom_adjust_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
@@ -2013,7 +2062,7 @@ static const struct pid_entry tgid_base_
DIR("task", S_IRUGO|S_IXUGO, task),
DIR("fd", S_IRUSR|S_IXUSR, fd),
DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo),
- INF("environ", S_IRUSR, pid_environ),
+ REG("environ", S_IRUSR, environ),
INF("auxv", S_IRUSR, pid_auxv),
INF("status", S_IRUGO, pid_status),
#ifdef CONFIG_SCHED_DEBUG
@@ -2303,7 +2352,7 @@ out_no_task:
static const struct pid_entry tid_base_stuff[] = {
DIR("fd", S_IRUSR|S_IXUSR, fd),
DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo),
- INF("environ", S_IRUSR, pid_environ),
+ REG("environ", S_IRUSR, environ),
INF("auxv", S_IRUSR, pid_auxv),
INF("status", S_IRUGO, pid_status),
#ifdef CONFIG_SCHED_DEBUG
_
Patches currently in -mm which might be from james-p@xxxxxxxxxxxxxxxxxx are
dont-truncate-proc-pid-environ-at-4096-characters.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
