Thread (11 messages) flat view 11 messages, 4 authors, 2021-06-22
STALE1876d

[PATCH net-next 6/7] ethtool: Validate module EEPROM length as part of policy

From: Ido Schimmel <hidden>
Date: 2021-06-22 06:52:15
Subsystem: networking [ethtool], networking [general], the rest · Maintainers: Andrew Lunn, Jakub Kicinski, "David S. Miller", Eric Dumazet, Paolo Abeni, Linus Torvalds

From: Ido Schimmel <idosch@nvidia.com>

Validate the number of bytes to read from the module EEPROM as part of
the netlink policy and remove the corresponding check from the code.

This also makes it possible to query the length range from user space:

 $ genl ctrl policy name ethtool
 ...
 ID: 0x14  policy[32]:attr[3]: type=U32 range:[1,128]
 ...

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
---
 net/ethtool/eeprom.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/net/ethtool/eeprom.c b/net/ethtool/eeprom.c
index 5d38e90895ac..1e75d9c1b154 100644
--- a/net/ethtool/eeprom.c
+++ b/net/ethtool/eeprom.c
@@ -159,9 +159,6 @@ static int eeprom_parse_request(struct ethnl_req_info *req_info, struct nlattr *
 	request->offset = nla_get_u32(tb[ETHTOOL_A_MODULE_EEPROM_OFFSET]);
 	request->length = nla_get_u32(tb[ETHTOOL_A_MODULE_EEPROM_LENGTH]);
 
-	if (!request->length)
-		return -EINVAL;
-
 	/* The following set of conditions limit the API to only dump 1/2
 	 * EEPROM page without crossing low page boundary located at offset 128.
 	 * This means user may only request dumps of length limited to 128 from
@@ -237,7 +234,8 @@ const struct ethnl_request_ops ethnl_module_eeprom_request_ops = {
 const struct nla_policy ethnl_module_eeprom_get_policy[] = {
 	[ETHTOOL_A_MODULE_EEPROM_HEADER]	= NLA_POLICY_NESTED(ethnl_header_policy),
 	[ETHTOOL_A_MODULE_EEPROM_OFFSET]	= { .type = NLA_U32 },
-	[ETHTOOL_A_MODULE_EEPROM_LENGTH]	= { .type = NLA_U32 },
+	[ETHTOOL_A_MODULE_EEPROM_LENGTH]	=
+		NLA_POLICY_RANGE(NLA_U32, 1, ETH_MODULE_EEPROM_PAGE_LEN),
 	[ETHTOOL_A_MODULE_EEPROM_PAGE]		= { .type = NLA_U8 },
 	[ETHTOOL_A_MODULE_EEPROM_BANK]		= { .type = NLA_U8 },
 	[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS]	=
-- 
2.31.1
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help