hw/scsi/lsi53c895a: add missing decrement of reentrancy counter

When the maximum count of SCRIPTS instructions is reached, the code
stops execution and returns, but fails to decrement the reentrancy
counter. This effectively renders the SCSI controller unusable
because on next entry the reentrancy counter is still above the limit.

This bug was seen on HP-UX 10.20 which seems to trigger SCRIPTS
loops.

Fixes: b987718bbb ("hw/scsi/lsi53c895a: Fix reentrancy issues in the LSI controller (CVE-2023-0330)")
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Message-ID: <20240128202214.2644768-1-svens@stackframe.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This commit is contained in:
Sven Schnelle 2024-01-28 21:22:14 +01:00 committed by Thomas Huth
parent 39a6e4f87e
commit 8b09b7fe47

View file

@ -1159,6 +1159,7 @@ again:
lsi_script_scsi_interrupt(s, LSI_SIST0_UDC, 0);
lsi_disconnect(s);
trace_lsi_execute_script_stop();
reentrancy_level--;
return;
}
insn = read_dword(s, s->dsp);