5.4-stable review patch. If anyone has any objections, please let me know.
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From: Andrew Morton akpm@linux-foundation.org
commit 50695153d7ddde3b1696dbf0085be0033bf3ddb3 upstream.
In
riocm_cdev_ioctl(RIO_CM_CHAN_SEND) -> cm_chan_msg_send() -> riocm_ch_send()
cm_chan_msg_send() checks that userspace didn't send too much data but riocm_ch_send() failed to check that userspace sent sufficient data. The result is that riocm_ch_send() can write to fields in the rio_ch_chan_hdr which were outside the bounds of the space which cm_chan_msg_send() allocated.
Address this by teaching riocm_ch_send() to check that the entire rio_ch_chan_hdr was copied in from userspace.
Reported-by: maher azz maherazz04@gmail.com Cc: Matt Porter mporter@kernel.crashing.org Cc: Alexandre Bounine alex.bou9@gmail.com Cc: Linus Torvalds torvalds@linuxfoundation.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/rapidio/rio_cm.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/rapidio/rio_cm.c +++ b/drivers/rapidio/rio_cm.c @@ -787,6 +787,9 @@ static int riocm_ch_send(u16 ch_id, void if (buf == NULL || ch_id == 0 || len == 0 || len > RIO_MAX_MSG_SIZE) return -EINVAL;
+ if (len < sizeof(struct rio_ch_chan_hdr)) + return -EINVAL; /* insufficient data from user */ + ch = riocm_get_channel(ch_id); if (!ch) { riocm_error("%s(%d) ch_%d not found", current->comm,