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authorLinus Torvalds2022-01-02 10:36:09 -0800
committerLinus Torvalds2022-01-02 10:36:09 -0800
commit859431ac11aef9b4cd7ffa75e94a92a6a41c8623 (patch)
treeb2b6b812e7aba7c0159e05cfc972edde5e00658f
parent1286cc4893cf356ad6c3a042116981e827dd3680 (diff)
parentc116fe1e1883ad3eda0a1938a9e3275a98aa51a5 (diff)
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang: "Better input validation for compat ioctls and a documentation bugfix for 5.16" * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: Docs: Fixes link to I2C specification i2c: validate user data in compat ioctl
-rw-r--r--Documentation/i2c/summary.rst8
-rw-r--r--drivers/i2c/i2c-dev.c3
2 files changed, 8 insertions, 3 deletions
diff --git a/Documentation/i2c/summary.rst b/Documentation/i2c/summary.rst
index 136c4e333be7..786c618ba3be 100644
--- a/Documentation/i2c/summary.rst
+++ b/Documentation/i2c/summary.rst
@@ -11,9 +11,11 @@ systems. Some systems use variants that don't meet branding requirements,
and so are not advertised as being I2C but come under different names,
e.g. TWI (Two Wire Interface), IIC.
-The official I2C specification is the `"I2C-bus specification and user
-manual" (UM10204) <https://www.nxp.com/docs/en/user-guide/UM10204.pdf>`_
-published by NXP Semiconductors.
+The latest official I2C specification is the `"I2C-bus specification and user
+manual" (UM10204) <https://www.nxp.com/webapp/Download?colCode=UM10204>`_
+published by NXP Semiconductors. However, you need to log-in to the site to
+access the PDF. An older version of the specification (revision 6) is archived
+`here <https://web.archive.org/web/20210813122132/https://www.nxp.com/docs/en/user-guide/UM10204.pdf>`_.
SMBus (System Management Bus) is based on the I2C protocol, and is mostly
a subset of I2C protocols and signaling. Many I2C devices will work on an
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index bce0e8bb7852..cf5d049342ea 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -535,6 +535,9 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
sizeof(rdwr_arg)))
return -EFAULT;
+ if (!rdwr_arg.msgs || rdwr_arg.nmsgs == 0)
+ return -EINVAL;
+
if (rdwr_arg.nmsgs > I2C_RDWR_IOCTL_MAX_MSGS)
return -EINVAL;