4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Colin Ian King colin.king@canonical.com
[ Upstream commit 67300abdbe9f1717532aaf4e037222762716d0f6 ]
Currently an out of range dev->nr is detected by just reporting the issue and later on an out-of-bounds read on array card occurs because of this. Fix this by checking the upper range of dev->nr with the size of array card (removes the hard coded size), move this check earlier and also exit with the error -ENOSYS to avoid the later out-of-bounds array read.
Detected by CoverityScan, CID#711191 ("Out-of-bounds-read")
Fixes: commit 02b20b0b4cde ("V4L/DVB (12730): Add conexant cx25821 driver")
Signed-off-by: Colin Ian King colin.king@canonical.com Signed-off-by: Hans Verkuil hans.verkuil@cisco.com [hans.verkuil@cisco.com: %ld -> %zd] Signed-off-by: Mauro Carvalho Chehab mchehab@s-opensource.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/pci/cx25821/cx25821-core.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/media/pci/cx25821/cx25821-core.c +++ b/drivers/media/pci/cx25821/cx25821-core.c @@ -867,6 +867,10 @@ static int cx25821_dev_setup(struct cx25 dev->nr = ++cx25821_devcount; sprintf(dev->name, "cx25821[%d]", dev->nr);
+ if (dev->nr >= ARRAY_SIZE(card)) { + CX25821_INFO("dev->nr >= %zd", ARRAY_SIZE(card)); + return -ENODEV; + } if (dev->pci->device != 0x8210) { pr_info("%s(): Exiting. Incorrect Hardware device = 0x%02x\n", __func__, dev->pci->device); @@ -882,9 +886,6 @@ static int cx25821_dev_setup(struct cx25 dev->channels[i].sram_channels = &cx25821_sram_channels[i]; }
- if (dev->nr > 1) - CX25821_INFO("dev->nr > 1!"); - /* board config */ dev->board = 1; /* card[dev->nr]; */ dev->_max_num_decoders = MAX_DECODERS;