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| author | kib <kib@FreeBSD.org> | 2014-12-19 09:36:59 +0000 |
|---|---|---|
| committer | kib <kib@FreeBSD.org> | 2014-12-19 09:36:59 +0000 |
| commit | 492a1d38b56fd9795afa90eb289407c047cd6000 (patch) | |
| tree | 5f73c9103f4a4a929bffffc74cc6417c69e4c4d2 | |
| parent | bf071386224cba73f4bec31a49ad96bc73e96677 (diff) | |
| download | FreeBSD-src-492a1d38b56fd9795afa90eb289407c047cd6000.zip FreeBSD-src-492a1d38b56fd9795afa90eb289407c047cd6000.tar.gz | |
MFC r275833:
The iret instruction may generate #np and #ss fault, besides #gp.
When returning to usermode, the handler for that exceptions is also
executed with wrong gs base. Handle all three possible faults in the
same way, checking for iret fault, and performing full iret.
| -rw-r--r-- | sys/amd64/amd64/exception.S | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/sys/amd64/amd64/exception.S b/sys/amd64/amd64/exception.S index 25b89d8..49d61f6 100644 --- a/sys/amd64/amd64/exception.S +++ b/sys/amd64/amd64/exception.S @@ -154,9 +154,13 @@ IDTVEC(xmm) IDTVEC(tss) TRAP_ERR(T_TSSFLT) IDTVEC(missing) - TRAP_ERR(T_SEGNPFLT) + subq $TF_ERR,%rsp + movl $T_SEGNPFLT,TF_TRAPNO(%rsp) + jmp prot_addrf IDTVEC(stk) - TRAP_ERR(T_STKFLT) + subq $TF_ERR,%rsp + movl $T_STKFLT,TF_TRAPNO(%rsp) + jmp prot_addrf IDTVEC(align) TRAP_ERR(T_ALIGNFLT) @@ -319,6 +323,7 @@ IDTVEC(page) IDTVEC(prot) subq $TF_ERR,%rsp movl $T_PROTFLT,TF_TRAPNO(%rsp) +prot_addrf: movq $0,TF_ADDR(%rsp) movq %rdi,TF_RDI(%rsp) /* free up a GP register */ leaq doreti_iret(%rip),%rdi |
