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>
(cherry picked from commit 8b09b7fe47)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Sven Schnelle 2024-01-28 21:22:14 +01:00 committed by Michael Tokarev
parent 3a970decfe
commit bbfcb0f7bc

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);