From: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> commit a44f9d6f9dc1fb314a3f1ed2dcd4fbbcc3d9f892 upstream. There is a wrong comparison of the total size of the loaded firmware css->fw->size with the size of a pointer to struct imgu_fw_header. Turn binary_header into a flexible-array member[1][2], use the struct_size() helper and fix the wrong size comparison. Notice that the loaded firmware needs to contain at least one 'struct imgu_fw_info' item in the binary_header[] array. It's also worth mentioning that "css->fw->size < struct_size(css->fwp, binary_header, 1)" with binary_header declared as a flexible-array member is equivalent to "css->fw->size < sizeof(struct imgu_fw_header)" with binary_header declared as a one-element array (as in the original code). The replacement of the one-element array with a flexible-array member also helps with the ongoing efforts to globally enable -Warray-bounds and get us closer to being able to tighten the FORTIFY_SOURCE routines on memcpy(). [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/109 Fixes: 09d290f0ba21 ("media: staging/intel-ipu3: css: Add support for firmware management") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/media/ipu3/ipu3-css-fw.c | 7 +++---- drivers/staging/media/ipu3/ipu3-css-fw.h | 2 +- 2 files changed, 4 insertions(+), 5 deletions(-) --- a/drivers/staging/media/ipu3/ipu3-css-fw.c +++ b/drivers/staging/media/ipu3/ipu3-css-fw.c @@ -124,12 +124,11 @@ int imgu_css_fw_init(struct imgu_css *cs /* Check and display fw header info */ css->fwp = (struct imgu_fw_header *)css->fw->data; - if (css->fw->size < sizeof(struct imgu_fw_header *) || + if (css->fw->size < struct_size(css->fwp, binary_header, 1) || css->fwp->file_header.h_size != sizeof(struct imgu_fw_bi_file_h)) goto bad_fw; - if (sizeof(struct imgu_fw_bi_file_h) + - css->fwp->file_header.binary_nr * sizeof(struct imgu_fw_info) > - css->fw->size) + if (struct_size(css->fwp, binary_header, + css->fwp->file_header.binary_nr) > css->fw->size) goto bad_fw; dev_info(dev, "loaded firmware version %.64s, %u binaries, %zu bytes\n", --- a/drivers/staging/media/ipu3/ipu3-css-fw.h +++ b/drivers/staging/media/ipu3/ipu3-css-fw.h @@ -170,7 +170,7 @@ struct imgu_fw_bi_file_h { struct imgu_fw_header { struct imgu_fw_bi_file_h file_header; - struct imgu_fw_info binary_header[1]; /* binary_nr items */ + struct imgu_fw_info binary_header[]; /* binary_nr items */ }; /******************* Firmware functions *******************/
