safesetid: check size of policy writes
[ Upstream commit f09ff307c7 ]
syzbot attempts to write a buffer with a large size to a sysfs entry
with writes handled by handle_policy_update(), triggering a warning
in kmalloc.
Check the size specified for write buffers before allocating.
Reported-by: syzbot+4eb7a741b3216020043a@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4eb7a741b3216020043a
Signed-off-by: Leo Stone <leocstone@gmail.com>
[PM: subject tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
committed by
Greg Kroah-Hartman
parent
52858d7fe6
commit
36b385d0f2
@@ -143,6 +143,9 @@ static ssize_t handle_policy_update(struct file *file,
|
||||
char *buf, *p, *end;
|
||||
int err;
|
||||
|
||||
if (len >= KMALLOC_MAX_SIZE)
|
||||
return -EINVAL;
|
||||
|
||||
pol = kmalloc(sizeof(struct setid_ruleset), GFP_KERNEL);
|
||||
if (!pol)
|
||||
return -ENOMEM;
|
||||
|
||||
Reference in New Issue
Block a user