Discussion:
[PATCH v2] ofnet: Initialize structs in bootpath parser
(too old to reply)
Julian Andres Klode
2018-09-03 08:09:15 UTC
Permalink
Code later on checks if variables inside the struct are
0 to see if they have been set, like if there were addresses
in the bootpath.

The variables were not initialized however, so the check
might succeed with uninitialized data, and a new interface
with random addresses and the same name is added. This causes
$net_default_mac to point to the random one, so, for example,
using that variable to load per-mac config files fails.

Bug-Ubuntu: https://bugs.launchpad.net/bugs/1785859
Signed-off-by: Julian Andres Klode <***@canonical.com>
---

Notes:
v2: Rewrote commit message to address review comments and make it look nicer

grub-core/net/drivers/ieee1275/ofnet.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/grub-core/net/drivers/ieee1275/ofnet.c b/grub-core/net/drivers/ieee1275/ofnet.c
index 002446be1..00abc64bb 100644
--- a/grub-core/net/drivers/ieee1275/ofnet.c
+++ b/grub-core/net/drivers/ieee1275/ofnet.c
@@ -153,8 +153,8 @@ grub_ieee1275_parse_bootpath (const char *devpath, char *bootpath,
char *comma_char = 0;
char *equal_char = 0;
grub_size_t field_counter = 0;
- grub_net_network_level_address_t client_addr, gateway_addr, subnet_mask;
- grub_net_link_level_address_t hw_addr;
+ grub_net_network_level_address_t client_addr = {}, gateway_addr = {}, subnet_mask = {};
+ grub_net_link_level_address_t hw_addr = {};
grub_net_interface_flags_t flags = 0;
struct grub_net_network_level_interface *inter = NULL;
grub_uint16_t vlantag = 0;
--
2.17.1
Daniel Kiper
2018-09-04 10:27:57 UTC
Permalink
Post by Julian Andres Klode
Code later on checks if variables inside the struct are
0 to see if they have been set, like if there were addresses
in the bootpath.
The variables were not initialized however, so the check
might succeed with uninitialized data, and a new interface
with random addresses and the same name is added. This causes
$net_default_mac to point to the random one, so, for example,
using that variable to load per-mac config files fails.
Bug-Ubuntu: https://bugs.launchpad.net/bugs/1785859
Reviewed-by: Daniel Kiper <***@oracle.com>

Daniel

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