summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorVincent Li <macli@brc.ubc.ca>2009-09-22 16:45:36 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-23 07:39:40 -0700
commitfb92a4b068be96799da3748c11cbd69760e44d7b (patch)
treeda10040b94e5a0b83de42008c369aa7c3242c333 /fs
parentacef82b873b6899d80e639317228f2104dae79a2 (diff)
downloadlinux-fb92a4b068be96799da3748c11cbd69760e44d7b.tar.gz
fs/proc/task_mmu.c v1: fix clear_refs_write() input sanity check
Andrew Morton pointed out similar string hacking and obfuscated check for zero-length input at the end of the function, David Rientjes suggested to use strict_strtol to replace simple_strtol, this patch cover above suggestions, add removing of leading and trailing whitespace from user input. It does not change function behavious. Signed-off-by: Vincent Li <macli@brc.ubc.ca> Acked-by: David Rientjes <rientjes@google.com> Cc: Matt Mackall <mpm@selenic.com> Cc: Amerigo Wang <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
-rw-r--r--fs/proc/task_mmu.c14
1 files changed, 6 insertions, 8 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 59e98fea34a4..366b1017a4f1 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -473,21 +473,20 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct task_struct *task;
- char buffer[PROC_NUMBUF], *end;
+ char buffer[PROC_NUMBUF];
struct mm_struct *mm;
struct vm_area_struct *vma;
- int type;
+ long type;
memset(buffer, 0, sizeof(buffer));
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count))
return -EFAULT;
- type = simple_strtol(buffer, &end, 0);
+ if (strict_strtol(strstrip(buffer), 10, &type))
+ return -EINVAL;
if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED)
return -EINVAL;
- if (*end == '\n')
- end++;
task = get_proc_task(file->f_path.dentry->d_inode);
if (!task)
return -ESRCH;
@@ -523,9 +522,8 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
mmput(mm);
}
put_task_struct(task);
- if (end - buffer == 0)
- return -EIO;
- return end - buffer;
+
+ return count;
}
const struct file_operations proc_clear_refs_operations = {