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user backtrace fix #291
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user backtrace fix #291
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Changed it from no backtrace prints to a warning. |
if (thread->user_registers_->rbp % sizeof(pointer)) | ||
{ | ||
debug(BACKTRACE, "stack not aligned. this could cause serious problems\n"); | ||
return 0; |
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is this return intentionally here?
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left it in by mistake.
already removed it
Made a small mistake there. with correct 16 byte alignment the old code was fine. |
checkAddressValid panics when given a non-canonical address due to the new assert in resolveMapping.
A user could trigger this by crashing with a non-canonical address in rbp.
Add an extra check in checkAddressValid since it should never assert.
An incorrectly aligned user-space stack could make the user backtrace function read from an incorrect page in the identity mapping. This can lead to a crash due to a read from non-existing physical memory.