linux/drivers/i2c
Jeremy Compostella 4a6efb0107 i2c: core-smbus: prevent stack corruption on read I2C_BLOCK_DATA
commit 89c6efa61f upstream.

On a I2C_SMBUS_I2C_BLOCK_DATA read request, if data->block[0] is
greater than I2C_SMBUS_BLOCK_MAX + 1, the underlying I2C driver writes
data out of the msgbuf1 array boundary.

It is possible from a user application to run into that issue by
calling the I2C_SMBUS ioctl with data.block[0] greater than
I2C_SMBUS_BLOCK_MAX + 1.

This patch makes the code compliant with
Documentation/i2c/dev-interface by raising an error when the requested
size is larger than 32 bytes.

Call Trace:
 [<ffffffff8139f695>] dump_stack+0x67/0x92
 [<ffffffff811802a4>] panic+0xc5/0x1eb
 [<ffffffff810ecb5f>] ? vprintk_default+0x1f/0x30
 [<ffffffff817456d3>] ? i2cdev_ioctl_smbus+0x303/0x320
 [<ffffffff8109a68b>] __stack_chk_fail+0x1b/0x20
 [<ffffffff817456d3>] i2cdev_ioctl_smbus+0x303/0x320
 [<ffffffff81745aed>] i2cdev_ioctl+0x4d/0x1e0
 [<ffffffff811f761a>] do_vfs_ioctl+0x2ba/0x490
 [<ffffffff81336e43>] ? security_file_ioctl+0x43/0x60
 [<ffffffff811f7869>] SyS_ioctl+0x79/0x90
 [<ffffffff81a22e97>] entry_SYSCALL_64_fastpath+0x12/0x6a

Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
History 2018-03-03 15:52:25 +00:00
..
algos Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2014-01-29 19:56:20 -08:00
busses i2c: ismt: Separate I2C block read from SMBus block read 2017-11-11 13:34:04 +00:00
muxes i2c: mux: pinctrl: mention correct module name in Kconfig help text 2017-11-11 13:32:57 +00:00
i2c-boardinfo.c i2c: Update the FSF address 2012-03-26 21:47:19 +02:00
i2c-core.c i2c: core-smbus: prevent stack corruption on read I2C_BLOCK_DATA 2018-03-03 15:52:25 +00:00
i2c-core.h i2c: Update the FSF address 2012-03-26 21:47:19 +02:00
i2c-dev.c i2c: fix kernel memory disclosure in dev interface 2017-03-16 02:26:58 +00:00
i2c-mux.c i2c: mux: Inherit retry count and timeout from parent for muxed bus 2013-12-12 22:39:28 +01:00
i2c-smbus.c Update Jean Delvare's e-mail address 2014-01-29 20:40:08 +01:00
i2c-stub.c Update Jean Delvare's e-mail address 2014-01-29 20:40:08 +01:00
Kconfig Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
Makefile i2c-stub: Move to drivers/i2c 2012-10-28 21:37:00 +01:00