This is a note to let you know that I've just added the patch titled
ipmi: ssif_bmc: prevent integer overflow on 32bit systems
to the 6.6-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:
ipmi-ssif_bmc-prevent-integer-overflow-on-32bit-syst.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c94e30b692d2a72c0b1aefe34e0fbd9ee1326674
Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Fri Jun 14 20:30:44 2024 +0300
ipmi: ssif_bmc: prevent integer overflow on 32bit systems
[ Upstream commit 0627cef36145c9ff9845bdfd7ddf485bbac1f981 ]
There are actually two bugs here. First, we need to ensure that count
is at least sizeof(u32) or msg.len will be uninitialized data.
The "msg.len" variable is a u32 that comes from the user. On 32bit
systems the "sizeof_field(struct ipmi_ssif_msg, len) + msg.len"
addition can overflow if "msg.len" is greater than U32_MAX - 4.
Valid lengths for "msg.len" are 1-254. Add a check for that to
prevent the integer overflow.
Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Message-Id: <1431ca2e-4e9c-4520-bfc0-6879313c30e9@moroto.mountain>
Signed-off-by: Corey Minyard <corey@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/char/ipmi/ssif_bmc.c b/drivers/char/ipmi/ssif_bmc.c
index 56346fb328727..ab4e87a99f087 100644
--- a/drivers/char/ipmi/ssif_bmc.c
+++ b/drivers/char/ipmi/ssif_bmc.c
@@ -177,13 +177,15 @@ static ssize_t ssif_bmc_write(struct file *file, const char __user *buf, size_t
unsigned long flags;
ssize_t ret;
- if (count > sizeof(struct ipmi_ssif_msg))
+ if (count < sizeof(msg.len) ||
+ count > sizeof(struct ipmi_ssif_msg))
return -EINVAL;
if (copy_from_user(&msg, buf, count))
return -EFAULT;
- if (!msg.len || count < sizeof_field(struct ipmi_ssif_msg, len) + msg.len)
+ if (!msg.len || msg.len > IPMI_SSIF_PAYLOAD_MAX ||
+ count < sizeof_field(struct ipmi_ssif_msg, len) + msg.len)
return -EINVAL;
spin_lock_irqsave(&ssif_bmc->lock, flags);
