[PATCH][next] staging: greybus: i2c: Use struct_size() helper in gb_i2c_operation_create()
Make use of the struct_size() helper instead of an open-coded version, in order to avoid any potential type mistakes or integer overflows that, in the worst scenario, could lead to heap overflows.
Also, address the following sparse warnings: drivers/staging/greybus/i2c.c:111:24: warning: using sizeof on a flexible structure
Link: https://github.com/KSPP/linux/issues/174 Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org --- drivers/staging/greybus/i2c.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/staging/greybus/i2c.c b/drivers/staging/greybus/i2c.c index de2f6516da09..9dfc6791c20e 100644 --- a/drivers/staging/greybus/i2c.c +++ b/drivers/staging/greybus/i2c.c @@ -108,9 +108,7 @@ gb_i2c_operation_create(struct gb_connection *connection, else data_out_size += (u32)msg->len;
- request_size = sizeof(*request); - request_size += msg_count * sizeof(*op); - request_size += data_out_size; + request_size = struct_size(request, ops, msg_count) + data_out_size;
/* Response consists only of incoming data */ operation = gb_operation_create(connection, GB_I2C_TYPE_TRANSFER,
On Fri, Jan 21, 2022 at 04:22:50PM -0600, Gustavo A. R. Silva wrote:
Make use of the struct_size() helper instead of an open-coded version, in order to avoid any potential type mistakes or integer overflows that, in the worst scenario, could lead to heap overflows.
Also, address the following sparse warnings: drivers/staging/greybus/i2c.c:111:24: warning: using sizeof on a flexible structure
Link: https://github.com/KSPP/linux/issues/174 Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org
drivers/staging/greybus/i2c.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/staging/greybus/i2c.c b/drivers/staging/greybus/i2c.c index de2f6516da09..9dfc6791c20e 100644 --- a/drivers/staging/greybus/i2c.c +++ b/drivers/staging/greybus/i2c.c @@ -108,9 +108,7 @@ gb_i2c_operation_create(struct gb_connection *connection, else data_out_size += (u32)msg->len;
- request_size = sizeof(*request);
- request_size += msg_count * sizeof(*op);
- request_size += data_out_size;
- request_size = struct_size(request, ops, msg_count) + data_out_size;
This could still overflow if struct_size() returns SIZE_MAX. Perhaps:
if (check_add_overflow(struct_size(request, ops, msg_count), data_out_size, &request_size)) request_size = SIZE_MAX;
I should brush off the saturating arithmetic helpers series: https://lore.kernel.org/all/20210920180853.1825195-1-keescook@chromium.org/
/* Response consists only of incoming data */ operation = gb_operation_create(connection, GB_I2C_TYPE_TRANSFER, -- 2.27.0
On Mon, Jan 24, 2022 at 12:19:03PM -0800, Kees Cook wrote:
On Fri, Jan 21, 2022 at 04:22:50PM -0600, Gustavo A. R. Silva wrote:
Make use of the struct_size() helper instead of an open-coded version, in order to avoid any potential type mistakes or integer overflows that, in the worst scenario, could lead to heap overflows.
Also, address the following sparse warnings: drivers/staging/greybus/i2c.c:111:24: warning: using sizeof on a flexible structure
Link: https://github.com/KSPP/linux/issues/174 Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org
drivers/staging/greybus/i2c.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/staging/greybus/i2c.c b/drivers/staging/greybus/i2c.c index de2f6516da09..9dfc6791c20e 100644 --- a/drivers/staging/greybus/i2c.c +++ b/drivers/staging/greybus/i2c.c @@ -108,9 +108,7 @@ gb_i2c_operation_create(struct gb_connection *connection, else data_out_size += (u32)msg->len;
- request_size = sizeof(*request);
- request_size += msg_count * sizeof(*op);
- request_size += data_out_size;
- request_size = struct_size(request, ops, msg_count) + data_out_size;
This could still overflow if struct_size() returns SIZE_MAX. Perhaps:
uggh... I got too excited with all the new cases reported.
if (check_add_overflow(struct_size(request, ops, msg_count), data_out_size, &request_size)) request_size = SIZE_MAX;
Yep; I'll respin and include this change, thanks!
I should brush off the saturating arithmetic helpers series: https://lore.kernel.org/all/20210920180853.1825195-1-keescook@chromium.org/
Yeah; those helpers are very much needed in many places we need to audit...
-- Gustavo
On Mon, Jan 24, 2022 at 12:19:03PM -0800, Kees Cook wrote:
This could still overflow if struct_size() returns SIZE_MAX. Perhaps:
if (check_add_overflow(struct_size(request, ops, msg_count), data_out_size, &request_size)) request_size = SIZE_MAX;
I should brush off the saturating arithmetic helpers series: https://lore.kernel.org/all/20210920180853.1825195-1-keescook@chromium.org/
Yes, please! Those seem like a million times easier to use.
regards, dan carpenter
On Wed, Jan 26, 2022 at 01:54:04PM +0300, Dan Carpenter wrote:
On Mon, Jan 24, 2022 at 12:19:03PM -0800, Kees Cook wrote:
This could still overflow if struct_size() returns SIZE_MAX. Perhaps:
if (check_add_overflow(struct_size(request, ops, msg_count), data_out_size, &request_size)) request_size = SIZE_MAX;
I should brush off the saturating arithmetic helpers series: https://lore.kernel.org/all/20210920180853.1825195-1-keescook@chromium.org/
Yes, please! Those seem like a million times easier to use.
Here they are! :) Please review:
https://lore.kernel.org/lkml/20220124232342.3113350-1-keescook@chromium.org/
Thanks!
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Dan Carpenter -
Gustavo A. R. Silva -
Kees Cook