+-- On Thu, 27 Aug 2020, P J P wrote --+ | While transferring data via fdctrl_write_data(), check that | current drive does not have a null block pointer. Avoid | null pointer dereference. | | -> https://ruhr-uni-bochum.sciebo.de/s/NNWP2GfwzYKeKwE?path=%2Ffdc_nullptr1 | ==1658854==Hint: address points to the zero page. | #0 blk_inc_in_flight block/block-backend.c:1327 | #1 blk_prw block/block-backend.c:1299 | #2 blk_pwrite block/block-backend.c:1464 | #3 fdctrl_write_data hw/block/fdc.c:2418 | #4 fdctrl_write hw/block/fdc.c:962 | #5 portio_write ioport.c:205 | #6 memory_region_write_accessor memory.c:483 | #7 access_with_adjusted_size memory.c:544 | #8 memory_region_dispatch_write memory.c:1476 | | Reported-by: Ruhr-University <bugs-sys...@rub.de> | Signed-off-by: Prasad J Pandit <p...@fedoraproject.org> | --- | hw/block/fdc.c | 3 ++- | 1 file changed, 2 insertions(+), 1 deletion(-) | | diff --git a/hw/block/fdc.c b/hw/block/fdc.c | index e9ed3eef45..dedadac68a 100644 | --- a/hw/block/fdc.c | +++ b/hw/block/fdc.c | @@ -2419,7 +2419,8 @@ static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value) | if (pos == FD_SECTOR_LEN - 1 || | fdctrl->data_pos == fdctrl->data_len) { | cur_drv = get_cur_drv(fdctrl); | - if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo, | + if (cur_drv->blk | + && blk_pwrite(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo, | BDRV_SECTOR_SIZE, 0) < 0) { | FLOPPY_DPRINTF("error writing sector %d\n", | fd_sector(cur_drv)); |
Ping...! -- Prasad J Pandit / Red Hat Product Security Team 8685 545E B54C 486B C6EB 271E E285 8B5A F050 DE8D