summaryrefslogtreecommitdiffstats
path: root/fs/proc/base.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/proc/base.c')
-rw-r--r--fs/proc/base.c141
1 files changed, 53 insertions, 88 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9cde9edf9c4..3b42c1418f3 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -198,26 +198,6 @@ static int proc_root_link(struct dentry *dentry, struct path *path)
return result;
}
-static struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
-{
- struct mm_struct *mm;
- int err;
-
- err = mutex_lock_killable(&task->signal->cred_guard_mutex);
- if (err)
- return ERR_PTR(err);
-
- mm = get_task_mm(task);
- if (mm && mm != current->mm &&
- !ptrace_may_access(task, mode)) {
- mmput(mm);
- mm = ERR_PTR(-EACCES);
- }
- mutex_unlock(&task->signal->cred_guard_mutex);
-
- return mm;
-}
-
struct mm_struct *mm_for_maps(struct task_struct *task)
{
return mm_access(task, PTRACE_MODE_READ);
@@ -711,6 +691,13 @@ static int mem_open(struct inode* inode, struct file* file)
if (IS_ERR(mm))
return PTR_ERR(mm);
+ if (mm) {
+ /* ensure this mm_struct can't be freed */
+ atomic_inc(&mm->mm_count);
+ /* but do not pin its memory */
+ mmput(mm);
+ }
+
/* OK to pass negative loff_t, we can catch out-of-range */
file->f_mode |= FMODE_UNSIGNED_OFFSET;
file->private_data = mm;
@@ -718,57 +705,13 @@ static int mem_open(struct inode* inode, struct file* file)
return 0;
}
-static ssize_t mem_read(struct file * file, char __user * buf,
- size_t count, loff_t *ppos)
+static ssize_t mem_rw(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos, int write)
{
- int ret;
- char *page;
- unsigned long src = *ppos;
struct mm_struct *mm = file->private_data;
-
- if (!mm)
- return 0;
-
- page = (char *)__get_free_page(GFP_TEMPORARY);
- if (!page)
- return -ENOMEM;
-
- ret = 0;
-
- while (count > 0) {
- int this_len, retval;
-
- this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
- retval = access_remote_vm(mm, src, page, this_len, 0);
- if (!retval) {
- if (!ret)
- ret = -EIO;
- break;
- }
-
- if (copy_to_user(buf, page, retval)) {
- ret = -EFAULT;
- break;
- }
-
- ret += retval;
- src += retval;
- buf += retval;
- count -= retval;
- }
- *ppos = src;
-
- free_page((unsigned long) page);
- return ret;
-}
-
-static ssize_t mem_write(struct file * file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- int copied;
+ unsigned long addr = *ppos;
+ ssize_t copied;
char *page;
- unsigned long dst = *ppos;
- struct mm_struct *mm = file->private_data;
if (!mm)
return 0;
@@ -778,31 +721,54 @@ static ssize_t mem_write(struct file * file, const char __user *buf,
return -ENOMEM;
copied = 0;
+ if (!atomic_inc_not_zero(&mm->mm_users))
+ goto free;
+
while (count > 0) {
- int this_len, retval;
+ int this_len = min_t(int, count, PAGE_SIZE);
- this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
- if (copy_from_user(page, buf, this_len)) {
+ if (write && copy_from_user(page, buf, this_len)) {
copied = -EFAULT;
break;
}
- retval = access_remote_vm(mm, dst, page, this_len, 1);
- if (!retval) {
+
+ this_len = access_remote_vm(mm, addr, page, this_len, write);
+ if (!this_len) {
if (!copied)
copied = -EIO;
break;
}
- copied += retval;
- buf += retval;
- dst += retval;
- count -= retval;
+
+ if (!write && copy_to_user(buf, page, this_len)) {
+ copied = -EFAULT;
+ break;
+ }
+
+ buf += this_len;
+ addr += this_len;
+ copied += this_len;
+ count -= this_len;
}
- *ppos = dst;
+ *ppos = addr;
+ mmput(mm);
+free:
free_page((unsigned long) page);
return copied;
}
+static ssize_t mem_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return mem_rw(file, buf, count, ppos, 0);
+}
+
+static ssize_t mem_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return mem_rw(file, (char __user*)buf, count, ppos, 1);
+}
+
loff_t mem_lseek(struct file *file, loff_t offset, int orig)
{
switch (orig) {
@@ -822,8 +788,8 @@ loff_t mem_lseek(struct file *file, loff_t offset, int orig)
static int mem_release(struct inode *inode, struct file *file)
{
struct mm_struct *mm = file->private_data;
-
- mmput(mm);
+ if (mm)
+ mmdrop(mm);
return 0;
}
@@ -1344,8 +1310,7 @@ sched_autogroup_write(struct file *file, const char __user *buf,
if (!p)
return -ESRCH;
- err = nice;
- err = proc_sched_autogroup_set_nice(p, &err);
+ err = proc_sched_autogroup_set_nice(p, nice);
if (err)
count = err;
@@ -3024,9 +2989,9 @@ static const struct pid_entry tgid_base_stuff[] = {
INF("cmdline", S_IRUGO, proc_pid_cmdline),
ONE("stat", S_IRUGO, proc_tgid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
- REG("maps", S_IRUGO, proc_maps_operations),
+ REG("maps", S_IRUGO, proc_pid_maps_operations),
#ifdef CONFIG_NUMA
- REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
+ REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
#endif
REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
LNK("cwd", proc_cwd_link),
@@ -3037,7 +3002,7 @@ static const struct pid_entry tgid_base_stuff[] = {
REG("mountstats", S_IRUSR, proc_mountstats_operations),
#ifdef CONFIG_PROC_PAGE_MONITOR
REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
- REG("smaps", S_IRUGO, proc_smaps_operations),
+ REG("smaps", S_IRUGO, proc_pid_smaps_operations),
REG("pagemap", S_IRUGO, proc_pagemap_operations),
#endif
#ifdef CONFIG_SECURITY
@@ -3383,9 +3348,9 @@ static const struct pid_entry tid_base_stuff[] = {
INF("cmdline", S_IRUGO, proc_pid_cmdline),
ONE("stat", S_IRUGO, proc_tid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
- REG("maps", S_IRUGO, proc_maps_operations),
+ REG("maps", S_IRUGO, proc_tid_maps_operations),
#ifdef CONFIG_NUMA
- REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
+ REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
#endif
REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
LNK("cwd", proc_cwd_link),
@@ -3395,7 +3360,7 @@ static const struct pid_entry tid_base_stuff[] = {
REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
#ifdef CONFIG_PROC_PAGE_MONITOR
REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
- REG("smaps", S_IRUGO, proc_smaps_operations),
+ REG("smaps", S_IRUGO, proc_tid_smaps_operations),
REG("pagemap", S_IRUGO, proc_pagemap_operations),
#endif
#ifdef CONFIG_SECURITY
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-29 04:49:27 +0000