diff options
author | Thomas Huth <thuth@redhat.com> | 2022-12-01 19:44:43 +0100 |
---|---|---|
committer | Thomas Huth <thuth@redhat.com> | 2022-12-03 22:04:40 +0100 |
commit | 21be74a9a59d1e4954ebb59dcbee0fda0b19de00 (patch) | |
tree | 08c7b4fc054bcc9e9c79d92a4256bcfb6e2d7573 /target | |
parent | 0f0a9e4e5c38c45ca7e6ac09cb36db21d42ec6dd (diff) |
target/s390x/tcg: Fix and improve the SACF instruction
The SET ADDRESS SPACE CONTROL FAST instruction is not privileged, it can be
used from problem space, too. Just the switching to the home address space
is privileged and should still generate a privilege exception. This bug is
e.g. causing programs like Java that use the "getcpu" vdso kernel function
to crash (see https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=990417#26 ).
While we're at it, also check if DAT is not enabled. In that case the
instruction is supposed to generate a special operation exception.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/655
Message-Id: <20221201184443.136355-1-thuth@redhat.com>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Diffstat (limited to 'target')
-rw-r--r-- | target/s390x/tcg/cc_helper.c | 7 | ||||
-rw-r--r-- | target/s390x/tcg/insn-data.h.inc | 2 |
2 files changed, 8 insertions, 1 deletions
diff --git a/target/s390x/tcg/cc_helper.c b/target/s390x/tcg/cc_helper.c index b2e8d3d9f5..b36f8cdc8b 100644 --- a/target/s390x/tcg/cc_helper.c +++ b/target/s390x/tcg/cc_helper.c @@ -487,6 +487,10 @@ void HELPER(sacf)(CPUS390XState *env, uint64_t a1) { HELPER_LOG("%s: %16" PRIx64 "\n", __func__, a1); + if (!(env->psw.mask & PSW_MASK_DAT)) { + tcg_s390_program_interrupt(env, PGM_SPECIAL_OP, GETPC()); + } + switch (a1 & 0xf00) { case 0x000: env->psw.mask &= ~PSW_MASK_ASC; @@ -497,6 +501,9 @@ void HELPER(sacf)(CPUS390XState *env, uint64_t a1) env->psw.mask |= PSW_ASC_SECONDARY; break; case 0x300: + if ((env->psw.mask & PSW_MASK_PSTATE) != 0) { + tcg_s390_program_interrupt(env, PGM_PRIVILEGED, GETPC()); + } env->psw.mask &= ~PSW_MASK_ASC; env->psw.mask |= PSW_ASC_HOME; break; diff --git a/target/s390x/tcg/insn-data.h.inc b/target/s390x/tcg/insn-data.h.inc index 7e952bdfc8..54d4250c9f 100644 --- a/target/s390x/tcg/insn-data.h.inc +++ b/target/s390x/tcg/insn-data.h.inc @@ -1365,7 +1365,7 @@ /* SERVICE CALL LOGICAL PROCESSOR (PV hypercall) */ F(0xb220, SERVC, RRE, Z, r1_o, r2_o, 0, 0, servc, 0, IF_PRIV | IF_IO) /* SET ADDRESS SPACE CONTROL FAST */ - F(0xb279, SACF, S, Z, 0, a2, 0, 0, sacf, 0, IF_PRIV) + C(0xb279, SACF, S, Z, 0, a2, 0, 0, sacf, 0) /* SET CLOCK */ F(0xb204, SCK, S, Z, 0, m2_64a, 0, 0, sck, 0, IF_PRIV | IF_IO) /* SET CLOCK COMPARATOR */ |