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CPU: Prevent leakage of virtual addresses to kernel log

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Liav A 2020-03-06 16:45:53 +02:00 • committed by Andreas Kling
parent 5cbde297ec
commit 9991a36d1a
Notes: sideshowbarker 2024-07-19 08:52:02 +09:00
1 changed files with 8 additions and 8 deletions
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16
Kernel/Arch/i386/CPU.cpp
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@ -259,7 +259,7 @@ void page_fault_handler(RegisterState regs)
return;
}
klog() << "Unrecoverable page fault, "
dbg() << "Unrecoverable page fault, "
<< (regs.exception_code & PageFaultFlags::ReservedBitViolation ? "reserved bit violation / " : "")
<< (regs.exception_code & PageFaultFlags::InstructionFetch ? "instruction fetch / " : "")
<< (regs.exception_code & PageFaultFlags::Write ? "write to" : "read from")
@ -271,19 +271,19 @@ void page_fault_handler(RegisterState regs)
u32 slab_alloc_scrub_pattern = explode_byte(SLAB_ALLOC_SCRUB_BYTE);
u32 slab_dealloc_scrub_pattern = explode_byte(SLAB_DEALLOC_SCRUB_BYTE);
if ((fault_address & 0xffff0000) == (malloc_scrub_pattern & 0xffff0000)) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized malloc() memory";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized malloc() memory";
} else if ((fault_address & 0xffff0000) == (free_scrub_pattern & 0xffff0000)) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently free()'d memory";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently free()'d memory";
} else if ((fault_address & 0xffff0000) == (kmalloc_scrub_pattern & 0xffff0000)) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized kmalloc() memory";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized kmalloc() memory";
} else if ((fault_address & 0xffff0000) == (kfree_scrub_pattern & 0xffff0000)) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently kfree()'d memory";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently kfree()'d memory";
} else if ((fault_address & 0xffff0000) == (slab_alloc_scrub_pattern & 0xffff0000)) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized slab_alloc() memory";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized slab_alloc() memory";
} else if ((fault_address & 0xffff0000) == (slab_dealloc_scrub_pattern & 0xffff0000)) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently slab_dealloc()'d memory";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently slab_dealloc()'d memory";
} else if (fault_address < 4096) {
klog() << "Note: Address " << VirtualAddress(fault_address) << " looks like a possible nullptr dereference";
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like a possible nullptr dereference";
}
handle_crash(regs, "Page Fault", SIGSEGV);