On 9/3/20 9:08 AM, P J P wrote: > From: Prasad J Pandit <p...@fedoraproject.org> > > While doing multi block SDMA, transfer block size may exceed > the 's->fifo_buffer[s->buf_maxsz]' size. It may leave the > current element pointer 's->data_count' pointing out of bounds. > Leading the subsequent DMA r/w operation to OOB access issue. > Assert that 's->data_count' is within fifo_buffer. > > -> > https://ruhr-uni-bochum.sciebo.de/s/NNWP2GfwzYKeKwE?path=%2Fsdhci_oob_write1 > ==1459837==ERROR: AddressSanitizer: heap-buffer-overflow > WRITE of size 54722048 at 0x61500001e280 thread T3 > #0 __interceptor_memcpy (/lib64/libasan.so.6+0x3a71d) > #1 flatview_read_continue ../exec.c:3245 > #2 flatview_read ../exec.c:3278 > #3 address_space_read_full ../exec.c:3291 > #4 address_space_rw ../exec.c:3319 > #5 dma_memory_rw_relaxed ../include/sysemu/dma.h:87 > #6 dma_memory_rw ../include/sysemu/dma.h:110 > #7 dma_memory_read ../include/sysemu/dma.h:116 > #8 sdhci_sdma_transfer_multi_blocks ../hw/sd/sdhci.c:629 > #9 sdhci_write ../hw/sd/sdhci.c:1097 > #10 memory_region_write_accessor ../softmmu/memory.c:483 > ... > > Reported-by: Ruhr-University <bugs-sys...@rub.de> > Suggested-by: Philippe Mathieu-Daudé <f4...@amsat.org> > Signed-off-by: Prasad J Pandit <p...@fedoraproject.org> > --- > hw/sd/sdhci.c | 2 ++ > 1 file changed, 2 insertions(+) > > Update v1: use assert(3) calls > -> https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg00966.html > > diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c > index 1785d7e1f7..023acbed41 100644 > --- a/hw/sd/sdhci.c > +++ b/hw/sd/sdhci.c > @@ -604,6 +604,7 @@ static void sdhci_sdma_transfer_multi_blocks(SDHCIState > *s) > s->blkcnt--; > } > } > + assert(s->data_count <= s->buf_maxsz && s->data_count > begin); > dma_memory_write(s->dma_as, s->sdmasysad, > &s->fifo_buffer[begin], s->data_count - begin); > s->sdmasysad += s->data_count - begin; > @@ -626,6 +627,7 @@ static void sdhci_sdma_transfer_multi_blocks(SDHCIState > *s) > s->data_count = block_size; > boundary_count -= block_size - begin; > } > + assert(s->data_count <= s->buf_maxsz && s->data_count > begin); > dma_memory_read(s->dma_as, s->sdmasysad, > &s->fifo_buffer[begin], s->data_count - begin); > s->sdmasysad += s->data_count - begin; >
qemu-system-i386: hw/sd/sdhci.c:632: void sdhci_sdma_transfer_multi_blocks(SDHCIState *): Assertion `s->data_count <= s->buf_maxsz && s->data_count > begin' failed. Tested-by: Philippe Mathieu-Daudé <f4...@amsat.org> If you don't mind I might split the assert in 2 when applying: - assert(s->data_count <= s->buf_maxsz && s->data_count > begin); + assert(s->data_count <= s->buf_maxsz); + assert(s->data_count > begin); To directly display the problem straight: qemu-system-i386: hw/sd/sdhci.c:635: void sdhci_sdma_transfer_multi_blocks(SDHCIState *): Assertion `s->data_count > begin' failed. Thanks, Phil.