| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Mon, 15 Aug 2022 20:04:47 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Heiko Carstens <hca@...ux.ibm.com>,
Alexander Gordeev <agordeev@...ux.ibm.com>,
Vasily Gorbik <gor@...ux.ibm.com>,
Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.15 643/779] s390/maccess: rework absolute lowcore accessors
From: Alexander Gordeev <agordeev@...ux.ibm.com>
[ Upstream commit ed0192bc644f3553d64a5cb461bdd0b1fbae3fdf ]
Macro mem_assign_absolute() is able to access the whole memory, but
is only used and makes sense when updating the absolute lowcore.
Instead, introduce get_abs_lowcore() and put_abs_lowcore() macros
that limit access to absolute lowcore addresses only.
Suggested-by: Heiko Carstens <hca@...ux.ibm.com>
Reviewed-by: Heiko Carstens <hca@...ux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@...ux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@...ux.ibm.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
arch/s390/include/asm/processor.h | 17 ++++++++++++-----
arch/s390/kernel/ipl.c | 4 ++--
arch/s390/kernel/machine_kexec.c | 2 +-
arch/s390/kernel/os_info.c | 2 +-
arch/s390/kernel/setup.c | 19 ++++++++++---------
arch/s390/kernel/smp.c | 12 ++++++------
6 files changed, 32 insertions(+), 24 deletions(-)
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index e9db8efd50f2..d7ca76bb2720 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -321,11 +321,18 @@ extern void (*s390_base_pgm_handler_fn)(void);
extern int memcpy_real(void *, unsigned long, size_t);
extern void memcpy_absolute(void *, void *, size_t);
-#define mem_assign_absolute(dest, val) do { \
- __typeof__(dest) __tmp = (val); \
- \
- BUILD_BUG_ON(sizeof(__tmp) != sizeof(val)); \
- memcpy_absolute(&(dest), &__tmp, sizeof(__tmp)); \
+#define put_abs_lowcore(member, x) do { \
+ unsigned long __abs_address = offsetof(struct lowcore, member); \
+ __typeof__(((struct lowcore *)0)->member) __tmp = (x); \
+ \
+ memcpy_absolute(__va(__abs_address), &__tmp, sizeof(__tmp)); \
+} while (0)
+
+#define get_abs_lowcore(x, member) do { \
+ unsigned long __abs_address = offsetof(struct lowcore, member); \
+ __typeof__(((struct lowcore *)0)->member) *__ptr = &(x); \
+ \
+ memcpy_absolute(__ptr, __va(__abs_address), sizeof(*__ptr)); \
} while (0)
extern int s390_isolate_bp(void);
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 5ad1dde23dc5..ba2988783d66 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -1646,8 +1646,8 @@ static void dump_reipl_run(struct shutdown_trigger *trigger)
csum = (__force unsigned int)
csum_partial(reipl_block_actual, reipl_block_actual->hdr.len, 0);
- mem_assign_absolute(S390_lowcore.ipib, ipib);
- mem_assign_absolute(S390_lowcore.ipib_checksum, csum);
+ put_abs_lowcore(ipib, ipib);
+ put_abs_lowcore(ipib_checksum, csum);
dump_run(trigger);
}
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index 0505e55a6297..4b95684fbe46 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -227,7 +227,7 @@ void arch_crash_save_vmcoreinfo(void)
vmcoreinfo_append_str("SAMODE31=%lx\n", __samode31);
vmcoreinfo_append_str("EAMODE31=%lx\n", __eamode31);
vmcoreinfo_append_str("KERNELOFFSET=%lx\n", kaslr_offset());
- mem_assign_absolute(S390_lowcore.vmcore_info, paddr_vmcoreinfo_note());
+ put_abs_lowcore(vmcore_info, paddr_vmcoreinfo_note());
}
void machine_shutdown(void)
diff --git a/arch/s390/kernel/os_info.c b/arch/s390/kernel/os_info.c
index 6b5b64e67eee..1acc2e05d70f 100644
--- a/arch/s390/kernel/os_info.c
+++ b/arch/s390/kernel/os_info.c
@@ -63,7 +63,7 @@ void __init os_info_init(void)
os_info.version_minor = OS_INFO_VERSION_MINOR;
os_info.magic = OS_INFO_MAGIC;
os_info.csum = os_info_csum(&os_info);
- mem_assign_absolute(S390_lowcore.os_info, __pa(ptr));
+ put_abs_lowcore(os_info, __pa(ptr));
}
#ifdef CONFIG_CRASH_DUMP
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 36c1f31dfd66..6b1a8697fae8 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -479,11 +479,11 @@ static void __init setup_lowcore_dat_off(void)
lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
/* Setup absolute zero lowcore */
- mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
- mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
- mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
- mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
- mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
+ put_abs_lowcore(restart_stack, lc->restart_stack);
+ put_abs_lowcore(restart_fn, lc->restart_fn);
+ put_abs_lowcore(restart_data, lc->restart_data);
+ put_abs_lowcore(restart_source, lc->restart_source);
+ put_abs_lowcore(restart_psw, lc->restart_psw);
lc->spinlock_lockval = arch_spin_lockval(0);
lc->spinlock_index = 0;
@@ -500,6 +500,7 @@ static void __init setup_lowcore_dat_off(void)
static void __init setup_lowcore_dat_on(void)
{
struct lowcore *lc = lowcore_ptr[0];
+ int cr;
__ctl_clear_bit(0, 28);
S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
@@ -508,10 +509,10 @@ static void __init setup_lowcore_dat_on(void)
S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
__ctl_store(S390_lowcore.cregs_save_area, 0, 15);
__ctl_set_bit(0, 28);
- mem_assign_absolute(S390_lowcore.restart_flags, RESTART_FLAG_CTLREGS);
- mem_assign_absolute(S390_lowcore.program_new_psw, lc->program_new_psw);
- memcpy_absolute(&S390_lowcore.cregs_save_area, lc->cregs_save_area,
- sizeof(S390_lowcore.cregs_save_area));
+ put_abs_lowcore(restart_flags, RESTART_FLAG_CTLREGS);
+ put_abs_lowcore(program_new_psw, lc->program_new_psw);
+ for (cr = 0; cr < ARRAY_SIZE(lc->cregs_save_area); cr++)
+ put_abs_lowcore(cregs_save_area[cr], lc->cregs_save_area[cr]);
}
static struct resource code_resource = {
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 7bbcb5b8d3f6..35af70ed58fc 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -334,10 +334,10 @@ static void pcpu_delegate(struct pcpu *pcpu,
lc->restart_data = (unsigned long)data;
lc->restart_source = source_cpu;
} else {
- mem_assign_absolute(lc->restart_stack, stack);
- mem_assign_absolute(lc->restart_fn, (unsigned long)func);
- mem_assign_absolute(lc->restart_data, (unsigned long)data);
- mem_assign_absolute(lc->restart_source, source_cpu);
+ put_abs_lowcore(restart_stack, stack);
+ put_abs_lowcore(restart_fn, (unsigned long)func);
+ put_abs_lowcore(restart_data, (unsigned long)data);
+ put_abs_lowcore(restart_source, source_cpu);
}
__bpon();
asm volatile(
@@ -593,9 +593,9 @@ void smp_ctl_set_clear_bit(int cr, int bit, bool set)
parms.andval = ~(1UL << bit);
}
spin_lock(&ctl_lock);
- memcpy_absolute(&ctlreg, &S390_lowcore.cregs_save_area[cr], sizeof(ctlreg));
+ get_abs_lowcore(ctlreg, cregs_save_area[cr]);
ctlreg = (ctlreg & parms.andval) | parms.orval;
- memcpy_absolute(&S390_lowcore.cregs_save_area[cr], &ctlreg, sizeof(ctlreg));
+ put_abs_lowcore(cregs_save_area[cr], ctlreg);
spin_unlock(&ctl_lock);
on_each_cpu(smp_ctl_bit_callback, &parms, 1);
}
--
2.35.1
Powered by blists - more mailing lists