diff options
Diffstat (limited to 'results/classifier/deepseek-2-tmp/output/hypervisor/1921948')
| -rw-r--r-- | results/classifier/deepseek-2-tmp/output/hypervisor/1921948 | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/results/classifier/deepseek-2-tmp/output/hypervisor/1921948 b/results/classifier/deepseek-2-tmp/output/hypervisor/1921948 new file mode 100644 index 00000000..2746deb9 --- /dev/null +++ b/results/classifier/deepseek-2-tmp/output/hypervisor/1921948 @@ -0,0 +1,39 @@ + +MTE tags not checked properly for unaligned accesses at EL1 + +For kernel memory accesses that span across two memory granules, QEMU's MTE implementation only checks the tag of the first granule but not of the second one. + +To reproduce this, build the Linux kernel with CONFIG_KASAN_HW_TAGS enabled, apply the patch below, and boot the kernel: + +diff --git a/sound/last.c b/sound/last.c +index f0bb98780e70..04745cb30b74 100644 +--- a/sound/last.c ++++ b/sound/last.c +@@ -5,12 +5,18 @@ + */ + + #include <linux/init.h> ++#include <linux/slab.h> + #include <sound/core.h> + + static int __init alsa_sound_last_init(void) + { + struct snd_card *card; + int idx, ok = 0; ++ ++ char *ptr = kmalloc(128, GFP_KERNEL); ++ pr_err("KASAN report should follow:\n"); ++ *(volatile unsigned long *)(ptr + 124); ++ kfree(ptr); + + printk(KERN_INFO "ALSA device list:\n"); + for (idx = 0; idx < SNDRV_CARDS; idx++) { + +KASAN tags the 128 allocated bytes with the same tag as the returned pointer. The memory granule that follows the 128 allocated bytes has a different tag (with 1/15 probability). + +Expected result: a tag fault is detected and a KASAN report is printed when accessing bytes [124, 130). +Observed result: no tag fault is detected and no KASAN report is printed. + +Here are the flags that I use to run QEMU if they matter: + +qemu-system-aarch64 -s -machine virt,mte=on -cpu max -m 2G -smp 2 -net user,host=10.0.2.10,hostfwd=tcp:127.0.0.1:10021-:22 -net nic -nographic -kernel ./Image -append "console=ttyAMA0 root=/dev/vda earlyprintk=serial" -drive file=./fs.img,format=raw,if=virtio -no-shutdown -no-reboot \ No newline at end of file |