diff options
| author | Bartosz Szpila <bszpila@google.com> | 2026-10-01 08:57:13 +0000 |
|---|---|---|
| committer | Tzung-Bi Shih <tzungbi@kernel.org> | 2026-10-02 02:11:44 +0000 |
| commit | 317e7abcaf60b79765dcf35c014edac8b9d37a6e (patch) | |
| tree | 867303f96122fc7b7afa06ac1ffe574022df1dee /drivers/platform | |
| parent | 5859f97c6f404d07e89fe9c0d20a318ebf200bd1 (diff) | |
platform/chrome: cros_ec_typec: Validate SVID and mode counts in discovery data
cros_typec_register_altmodes() iterates over sop_disc->svid_count and
sop_disc->svids[i].mode_count from the EC_CMD_TYPEC_DISCOVERY response
without validating their bounds.
port->disc_data is allocated as a buffer of EC_PROTO2_MAX_RESPONSE_SIZE
bytes, and each SVID entry contains a fixed mode_vdo[6] array. If the EC
returns an out-of-bounds svid_count or mode_count, the loops read past
the end of the mode_vdo array or the disc_data buffer.
Validate that the discovery response with svid_count entries fits within
EC_PROTO2_MAX_RESPONSE_SIZE using struct_size(), and ensure each SVID's
mode_count does not exceed ARRAY_SIZE(sop_disc->svids[i].mode_vdo)
before registering altmodes.
Fixes: de0f49487db3 ("platform/chrome: cros_ec_typec: Register partner altmodes")
Signed-off-by: Bartosz Szpila <bszpila@google.com>
Reviewed-by: Andrei Kuchynski <akuchynski@chromium.org>
Link: https://lore.kernel.org/r/20261001085714.1086242-1-bszpila@google.com
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Diffstat (limited to 'drivers/platform')
| -rw-r--r-- | drivers/platform/chrome/cros_ec_typec.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c index 50a68819ceb7..4427897eb3f5 100644 --- a/drivers/platform/chrome/cros_ec_typec.c +++ b/drivers/platform/chrome/cros_ec_typec.c @@ -7,8 +7,10 @@ */ #include <linux/acpi.h> +#include <linux/array_size.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/overflow.h> #include <linux/platform_data/cros_ec_commands.h> #include <linux/platform_data/cros_usbpd_notify.h> #include <linux/platform_device.h> @@ -894,7 +896,15 @@ static int cros_typec_register_altmodes(struct cros_typec_data *typec, int port_ int ret = 0; int i, j; + if (struct_size(sop_disc, svids, sop_disc->svid_count) > EC_PROTO2_MAX_RESPONSE_SIZE) + return -EINVAL; + for (i = 0; i < sop_disc->svid_count; i++) { + if (sop_disc->svids[i].mode_count > ARRAY_SIZE(sop_disc->svids[i].mode_vdo)) { + ret = -EINVAL; + goto err_cleanup; + } + for (j = 0; j < sop_disc->svids[i].mode_count; j++) { memset(&desc, 0, sizeof(desc)); desc.svid = sop_disc->svids[i].svid; |