linux-kernel - [PATCH v2 11/11] i3c: master: svc: fix possible assignment of the same address to two devices

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240813-i3c_fix-v2-11-68fe4a050188@nxp.com>
Date: Tue, 13 Aug 2024 11:15:09 -0400
From: Frank Li <Frank.Li@....com>
To: Alexandre Belloni <alexandre.belloni@...tlin.com>, 
 Boris Brezillon <boris.brezillon@...labora.com>, 
 Parshuram Thombare <pthombar@...ence.com>, 
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>, 
 Boris Brezillon <bbrezillon@...nel.org>, Arnd Bergmann <arnd@...db.de>, 
 Miquel Raynal <miquel.raynal@...tlin.com>, 
 Conor Culhane <conor.culhane@...vaco.com>
Cc: linux-i3c@...ts.infradead.org, linux-kernel@...r.kernel.org, 
 imx@...ts.linux.dev, Frank Li <Frank.Li@....com>, stable@...nel.org
Subject: [PATCH v2 11/11] i3c: master: svc: fix possible assignment of the
 same address to two devices

svc_i3c_master_do_daa() {
    ...
    for (i = 0; i < dev_nb; i++) {
        ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
        if (ret)
            goto rpm_out;
    }
}

If two devices (A and B) are detected in DAA and address 0xa is assigned to
device A and 0xb to device B, a failure in i3c_master_add_i3c_dev_locked()
for device A (addr: 0xa) could prevent device B (addr: 0xb) from being
registered on the bus. The I3C stack might still consider 0xb a free
address. If a subsequent Hotjoin occurs, 0xb might be assigned to Device A,
causing both devices A and B to use the same address 0xb, violating the I3C
specification.

The return value for i3c_master_add_i3c_dev_locked() should not be checked
because subsequent steps will scan the entire I3C bus, independent of
whether i3c_master_add_i3c_dev_locked() returns success.

If device A registration fails, there is still a chance to register device
B. i3c_master_add_i3c_dev_locked() can reset DAA if a failure occurs while
retrieving device information.

Cc: stable@...nel.org
Fixes: 317bacf960a4 ("i3c: master: add enable(disable) hot join in sys entry")
Signed-off-by: Frank Li <Frank.Li@....com>
---
 drivers/i3c/master/svc-i3c-master.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 0de95f406c95b..f47e5f4af68c9 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -1041,11 +1041,8 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
 		goto rpm_out;

 	/* Register all devices who participated to the core */
-	for (i = 0; i < dev_nb; i++) {
-		ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
-		if (ret)
-			goto rpm_out;
-	}
+	for (i = 0; i < dev_nb; i++)
+		i3c_master_add_i3c_dev_locked(m, addrs[i]);

 	/* Configure IBI auto-rules */
 	ret = svc_i3c_update_ibirules(master);

-- 
2.34.1