45 lines
1.5 KiB
Diff
45 lines
1.5 KiB
Diff
From a2ef990ab5a6705a356d146dd773a3b359787497 Mon Sep 17 00:00:00 2001
|
|
From: Xiaotian Feng <xtfeng@gmail.com>
|
|
Date: Thu, 12 Jan 2012 17:17:08 -0800
|
|
Subject: [PATCH] proc: fix null pointer deref in proc_pid_permission()
|
|
|
|
get_proc_task() can fail to search the task and return NULL,
|
|
put_task_struct() will then bomb the kernel with following oops:
|
|
|
|
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
|
|
IP: [<ffffffff81217d34>] proc_pid_permission+0x64/0xe0
|
|
PGD 112075067 PUD 112814067 PMD 0
|
|
Oops: 0002 [#1] PREEMPT SMP
|
|
|
|
This is a regression introduced by commit 0499680a ("procfs: add hidepid=
|
|
and gid= mount options"). The kernel should return -ESRCH if
|
|
get_proc_task() failed.
|
|
|
|
Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com>
|
|
Cc: Al Viro <viro@zeniv.linux.org.uk>
|
|
Cc: Vasiliy Kulikov <segoon@openwall.com>
|
|
Cc: Stephen Wilson <wilsons@start.ca>
|
|
Acked-by: David Rientjes <rientjes@google.com>
|
|
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
---
|
|
fs/proc/base.c | 2 ++
|
|
1 files changed, 2 insertions(+), 0 deletions(-)
|
|
|
|
diff --git a/fs/proc/base.c b/fs/proc/base.c
|
|
index 8173dfd..5485a53 100644
|
|
--- a/fs/proc/base.c
|
|
+++ b/fs/proc/base.c
|
|
@@ -654,6 +654,8 @@ static int proc_pid_permission(struct inode *inode, int mask)
|
|
bool has_perms;
|
|
|
|
task = get_proc_task(inode);
|
|
+ if (!task)
|
|
+ return -ESRCH;
|
|
has_perms = has_pid_permissions(pid, task, 1);
|
|
put_task_struct(task);
|
|
|
|
--
|
|
1.7.7.5
|
|
|