This is a note to let you know that I've just added the patch titled
safesetid: check size of policy writes
to the 6.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
safesetid-check-size-of-policy-writes.patch
and it can be found in the queue-6.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f1dde6443717f232e30f19475b044e1c47fceaac
Author: Leo Stone <leocstone@xxxxxxxxx>
Date: Tue Dec 17 10:26:57 2024 -0800
safesetid: check size of policy writes
[ Upstream commit f09ff307c7299392f1c88f763299e24bc99811c7 ]
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@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=4eb7a741b3216020043a
Signed-off-by: Leo Stone <leocstone@xxxxxxxxx>
[PM: subject tweak]
Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/security/safesetid/securityfs.c b/security/safesetid/securityfs.c
index 25310468bcddf..8e1ffd70b18ab 100644
--- a/security/safesetid/securityfs.c
+++ b/security/safesetid/securityfs.c
@@ -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;
