From: Dan Carpenter Date: Tue, 25 Feb 2020 16:20:56 +0000 (+0300) Subject: libnvdimm: Out of bounds read in __nd_ioctl() X-Git-Tag: v5.7-rc1~45^2~2^2~1 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f84afbdd3a9e5e10633695677b95422572f920dc;p=thirdparty%2Fkernel%2Flinux.git libnvdimm: Out of bounds read in __nd_ioctl() 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 Link: https://lore.kernel.org/r/20200225162055.amtosfy7m35aivxg@kili.mountain Signed-off-by: Dan Williams --- diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c index a8b5159685699..09087c38fabdc 100644 --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -1042,8 +1042,10 @@ 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) */