diff options
| author | Christian Krinitsin <mail@krinitsin.com> | 2025-06-01 21:19:28 +0200 |
|---|---|---|
| committer | Christian Krinitsin <mail@krinitsin.com> | 2025-06-01 21:19:28 +0200 |
| commit | 05ed9b00104b3da2e9cb0d541b5c5bbceb027fde (patch) | |
| tree | d47bd9721b78db6131d56780e7230cf69412eaa6 /classification/semantic_issues/gitlab_semantic_bextr | |
| parent | cddf7dfa5a6e92a9057e7f6afae5d9b970585e6f (diff) | |
| download | qemu-analysis-05ed9b00104b3da2e9cb0d541b5c5bbceb027fde.tar.gz qemu-analysis-05ed9b00104b3da2e9cb0d541b5c5bbceb027fde.zip | |
adjust classifier
Diffstat (limited to 'classification/semantic_issues/gitlab_semantic_bextr')
| -rw-r--r-- | classification/semantic_issues/gitlab_semantic_bextr | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/classification/semantic_issues/gitlab_semantic_bextr b/classification/semantic_issues/gitlab_semantic_bextr new file mode 100644 index 000000000..dabe16acf --- /dev/null +++ b/classification/semantic_issues/gitlab_semantic_bextr @@ -0,0 +1,25 @@ +x86 BEXTR semantic bug +Description of problem +The result of instruction BEXTR is different with from the CPU. The value of destination register is different. I think QEMU does not consider the operand size limit. + +Steps to reproduce + +Compile this code + +void main() { + asm("mov rax, 0x17b3693f77fb6e9"); + asm("mov rbx, 0x8f635a775ad3b9b4"); + asm("mov rcx, 0xb717b75da9983018"); + asm("bextr eax, ebx, ecx"); +} + +Execute and compare the result with the CPU. + +CPU +RAX = 0x5a + +QEMU +RAX = 0x635a775a + +Additional information +This bug is discovered by research conducted by KAIST SoftSec. |