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Diffstat (limited to 'results/classifier/qwen3:32b/reasoning/runtime/1528239')
| -rw-r--r-- | results/classifier/qwen3:32b/reasoning/runtime/1528239 | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/results/classifier/qwen3:32b/reasoning/runtime/1528239 b/results/classifier/qwen3:32b/reasoning/runtime/1528239 new file mode 100644 index 00000000..029382d8 --- /dev/null +++ b/results/classifier/qwen3:32b/reasoning/runtime/1528239 @@ -0,0 +1,19 @@ +<think> +Okay, let's see. The user is having trouble debugging a PIE binary with QEMU's GDB stub. The problem is that when they set a breakpoint on main, they get an error about not being able to access memory at address 0x775, and the program exits immediately. + +First, I need to understand what PIE binaries are. PIE stands for Position Independent Executable. These are binaries that can be loaded at any memory address, which is a security feature. So, when you compile with -pie, the addresses in the binary aren't fixed. + +The user compiled their test program with -fPIC and -pie, which makes it a PIE. When they run it under QEMU with the GDB stub, GDB sets a breakpoint at 0x779, but when trying to re-set the breakpoint, it fails. The error is about not accessing memory at 0x775. + +The key here is that PIE binaries have their code loaded at different addresses each time. But in the GDB output, the breakpoint is set at 0x779. However, when the program starts, the actual _start function (from the dynamic linker) is at 0x4000a042d0. That address is way higher than 0x779, which suggests that the breakpoint was set at an incorrect address. + +Why is that happening? Because when the user loaded the binary into GDB with "file bad.x", GDB read the symbols from the PIE binary, but since PIE uses a base address of zero (or some arbitrary base), the addresses GDB thinks are correct don't match where the actual code is loaded in memory by QEMU. + +In normal non-PIE binaries, the addresses are fixed, so GDB can correctly set breakpoints. But with PIE, the actual load address is determined at runtime. So, when QEMU loads the PIE binary, it's placed at a different base address, but GDB, using the symbols from the binary, is trying to set breakpoints at addresses that are relative to the original (unloaded) base. Hence, the breakpoint addresses are wrong, leading to the memory access error when QEMU tries to set the breakpoint at that incorrect address. + +This seems to be an issue with how QEMU's GDB stub handles PIE binaries. The problem isn't with the instructions themselves or a syscall, but rather with how the runtime environment (QEMU) manages the loading and debugging of PIE executables. The GDB stub might not be correctly adjusting the addresses based on the actual load address of the PIE binary. + +Therefore, this is a runtime issue because it's about the dynamic behavior of loading and debugging the binary, not about incorrect instructions or syscalls. +</think> + +runtime \ No newline at end of file |