@@ -1211,17 +1211,18 @@ static sd_rsp_type_t sd_normal_command(SDState *sd, SDRequest req)
/* Writing in SPI mode not implemented. */
if (sd->spi)
break;
- sd->state = sd_receivingdata_state;
- sd->data_start = addr;
- sd->data_offset = 0;
- sd->blk_written = 0;
-
- if (sd->data_start + sd->blk_len > sd->size)
+ if (addr + sd->blk_len >= sd->size) {
sd->card_status |= ADDRESS_ERROR;
- if (sd_wp_addr(sd, sd->data_start))
+ } else if (sd_wp_addr(sd, sd->data_start)) {
sd->card_status |= WP_VIOLATION;
- if (sd->csd[14] & 0x30)
+ } else if (sd->csd[14] & 0x30) {
sd->card_status |= WP_VIOLATION;
+ } else {
+ sd->state = sd_receivingdata_state;
+ sd->data_start = addr;
+ sd->data_offset = 0;
+ sd->blk_written = 0;
+ }
return sd_r1;
default:
Avoid OOB access by verifying the requested address belong to the actual card size. Return ADDRESS_ERROR when not in range. Only move the state machine to ReceivingData if there is no pending error. "SD Specifications Part 1 Physical Layer Simplified Spec. v3.01" 4.3.4 Data Write * Block Write Write command is rejected if BLOCK_LEN_ERROR or ADDRESS_ERROR occurred and no data transfer is performed. Fixes: CVE-2020-13253 Reported-by: Alexander Bulekov <alxndr@bu.edu> Buglink: https://bugs.launchpad.net/qemu/+bug/1880822 Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> --- Cc: Prasad J Pandit <pjp@fedoraproject.org> v2: check for blksz in range, only go to sd_receivingdata_state if no error. --- hw/sd/sd.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-)