From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit f84afbdd3a9e5e10633695677b95422572f920dc ]
The "cmd" comes from the user and it can be up to 255. It it's more than the number of bits in long, it results out of bounds read when we check test_bit(cmd, &cmd_mask). The highest valid value for "cmd" is ND_CMD_CALL (10) so I added a compare against that.
Fixes: 62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Link: https://lore.kernel.org/r/20200225162055.amtosfy7m35aivxg@kili.mountain Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvdimm/bus.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c index 54a633e8cb5d2..48a070a37ea9b 100644 --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -984,8 +984,10 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, return -EFAULT; }
- if (!desc || (desc->out_num + desc->in_num == 0) || - !test_bit(cmd, &cmd_mask)) + if (!desc || + (desc->out_num + desc->in_num == 0) || + cmd > ND_CMD_CALL || + !test_bit(cmd, &cmd_mask)) return -ENOTTY;
/* fail write commands (when read-only) */