From ff9a3a01f25e1bed4d58ac67e97d7838d97e5055 Mon Sep 17 00:00:00 2001 From: Chenyuan Mi Date: Wed, 17 Apr 2024 12:25:58 -0400 Subject: [PATCH] tools: iio: iio_generic_buffer: Fix some integer type and calculation [ Upstream commit 49d736313d0975ddeb156f4f59801da833f78b30 ] In function size_from_channelarray(), the return value 'bytes' is defined as int type. However, the calcution of 'bytes' in this function is designed to use the unsigned int type. So it is necessary to change 'bytes' type to unsigned int to avoid integer overflow. The size_from_channelarray() is called in main() function, its return value is directly multipled by 'buf_len' and then used as the malloc() parameter. The 'buf_len' is completely controllable by user, thus a multiplication overflow may occur here. This could allocate an unexpected small area. Signed-off-by: Chenyuan Mi Link: https://lore.kernel.org/r/20230725092407.62545-1-michenyuan@huawei.com Signed-off-by: Jonathan Cameron Stable-dep-of: 2d3dff577dd0 ("tools: iio: iio_generic_buffer ensure alignment") Signed-off-by: Sasha Levin Signed-off-by: Harshit Mogalapalli --- tools/iio/iio_generic_buffer.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c index 87852ad36177..f0687a4cbae6 100644 --- a/tools/iio/iio_generic_buffer.c +++ b/tools/iio/iio_generic_buffer.c @@ -53,9 +53,9 @@ enum autochan { * Has the side effect of filling the channels[i].location values used * in processing the buffer output. **/ -static int size_from_channelarray(struct iio_channel_info *channels, int num_channels) +static unsigned int size_from_channelarray(struct iio_channel_info *channels, int num_channels) { - int bytes = 0; + unsigned int bytes = 0; int i = 0; while (i < num_channels) { @@ -343,7 +343,7 @@ int main(int argc, char **argv) ssize_t read_size; int dev_num = -1, trig_num = -1; char *buffer_access = NULL; - int scan_size; + unsigned int scan_size; int noevents = 0; int notrigger = 0; char *dummy; @@ -613,7 +613,16 @@ int main(int argc, char **argv) } scan_size = size_from_channelarray(channels, num_channels); - data = malloc(scan_size * buf_len); + + size_t total_buf_len = scan_size * buf_len; + + if (scan_size > 0 && total_buf_len / scan_size != buf_len) { + ret = -EFAULT; + perror("Integer overflow happened when calculate scan_size * buf_len"); + goto error; + } + + data = malloc(total_buf_len); if (!data) { ret = -ENOMEM; goto error;