Crash on startup with Apple GPU: null pointer in drmModifierName (Asahi Linux) #13407
Closed as not planned
Description
Description
Hyprland 0.54.0 crashes immediately on startup on Apple Silicon (M1) with Asahi Linux. The crash occurs in NFormatUtils::drmModifierName() when drmGetFormatModifierName() returns NULL for an unrecognized Apple GPU DRM modifier.
System Info
- Device: MacBook Air M1
- OS: Fedora Asahi Remix 42
- Kernel: 6.18.10-402.asahi.fc42.aarch64+16k
- GPU: Apple AGX (via asahi mesa driver)
- Hyprland: v0.54.0
Crash Backtrace (key frames)
Hyprland received signal 6(ABRT)
#12 | NFormatUtils::drmModifierName[abi:cxx11](unsigned long)
#13 | CDMABUFFormatTable::CDMABUFFormatTable(SDMABUFTranche, ...)
#16 | Hyprutils::Signal::CSignalListener::emitInternal(void*)
#18 | CCompositor::startCompositor()
#19 | main
Root Cause
In src/helpers/Format.cpp line 324, drmGetFormatModifierName(mod) returns NULL for unknown/vendor-specific DRM modifiers (such as those used by the Apple GPU driver). The result is passed directly to std::string constructor which throws std::logic_error on null input.
std::string NFormatUtils::drmModifierName(uint64_t mod) {
auto n = drmGetFormatModifierName(mod);
std::string name = n; // <-- crashes when n is NULL
free(n);
return name;
}Note: drmFormatName() just above has the same pattern and could also crash with unknown formats.
Fix
Add a null check:
std::string NFormatUtils::drmModifierName(uint64_t mod) {
auto n = drmGetFormatModifierName(mod);
std::string name = n ? n : "UNKNOWN";
free(n);
return name;
}This is confirmed working — Hyprland 0.54.0 built from source with this patch starts and runs correctly on Asahi Linux M1.
Log Tail (before crash)
DEBUG from aquamarine ]: GBM: Allocated a new buffer with size [Vector2D: x: 2560, y: 1600] and format XR24 with modifier 0 aka LINEAR
DEBUG from aquamarine ]: Swapchain: Reconfigured a swapchain to [Vector2D: x: 2560, y: 1600] XR24 of length 3
DEBUG from aquamarine ]: drm: Modesetting eDP-1 with 2560x1600@60.00Hz
ERR from aquamarine ]: drm: Cannot commit when a page-flip is awaiting