On Mon, Apr 01, 2019 at 01:54:41PM -0700, Connor O'Brien wrote:
From: Jeremy Compostella jeremy.compostella@intel.com
commit 89c6efa61f5709327ecfa24bff18e57a4e80c7fa 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 Cc: stable@kernel.org [connoro@google.com: 4.9 backport: adjust filename] Signed-off-by: Connor O'Brien connoro@google.com
drivers/i2c/i2c-core.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
Thanks for these, now applied.
greg k-h