commit f2c8aeb1afefcda92054c448b21fc59cdd99db30
author Jeuk Kim <jeuk20.kim@samsung.com> Mon Feb 05 12:20:15 2024 +0900
committer Jeuk Kim <jeuk20.kim@samsung.com> Mon Apr 29 12:13:35 2024 +0900
tree c2f6ffb7b1e5b311f5761da54b50694dd0681844
parent fd87be1dada5672f877e03c2ca8504458292c479

hw/ufs: Fix buffer overflow bug

It fixes the buffer overflow vulnerability in the ufs device.
The bug was detected by sanitizers.

You can reproduce it by:

cat << EOF |\
qemu-system-x86_64 \
-display none -machine accel=qtest -m 512M -M q35 -nodefaults -drive \
file=null-co://,if=none,id=disk0 -device ufs,id=ufs_bus -device \
ufs-lu,drive=disk0,bus=ufs_bus -qtest stdio
outl 0xcf8 0x80000810
outl 0xcfc 0xe0000000
outl 0xcf8 0x80000804
outw 0xcfc 0x06
write 0xe0000058 0x1 0xa7
write 0xa 0x1 0x50
EOF

Resolves: #2299
Fixes: 329f16624499 ("hw/ufs: Support for Query Transfer Requests")
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Jeuk Kim <jeuk20.kim@samsung.com>

hw/ufs/ufs.c

diff --git a/hw/ufs/ufs.c b/hw/ufs/ufs.c
index eccdb85..bac78a3 100644
--- a/hw/ufs/ufs.c
+++ b/hw/ufs/ufs.c
@@ -126,6 +126,10 @@
     copy_size = sizeof(UtpUpiuHeader) + UFS_TRANSACTION_SPECIFIC_FIELD_SIZE +
                 data_segment_length;
 
+    if (copy_size > sizeof(req->req_upiu)) {
+        copy_size = sizeof(req->req_upiu);
+    }
+
     ret = ufs_addr_read(u, req_upiu_base_addr, &req->req_upiu, copy_size);
     if (ret) {
         trace_ufs_err_dma_read_req_upiu(req->slot, req_upiu_base_addr);
@@ -225,6 +229,10 @@
         copy_size = rsp_upiu_byte_len;
     }
 
+    if (copy_size > sizeof(req->rsp_upiu)) {
+        copy_size = sizeof(req->rsp_upiu);
+    }
+
     ret = ufs_addr_write(u, rsp_upiu_base_addr, &req->rsp_upiu, copy_size);
     if (ret) {
         trace_ufs_err_dma_write_rsp_upiu(req->slot, rsp_upiu_base_addr);