| 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: Wed, 24 Jan 2024 22:21:45 -0800
From: debug@...osinc.com
To: rick.p.edgecombe@...el.com,
broonie@...nel.org,
Szabolcs.Nagy@....com,
kito.cheng@...ive.com,
keescook@...omium.org,
ajones@...tanamicro.com,
paul.walmsley@...ive.com,
palmer@...belt.com,
conor.dooley@...rochip.com,
cleger@...osinc.com,
atishp@...shpatra.org,
alex@...ti.fr,
bjorn@...osinc.com,
alexghiti@...osinc.com
Cc: corbet@....net,
aou@...s.berkeley.edu,
oleg@...hat.com,
akpm@...ux-foundation.org,
arnd@...db.de,
ebiederm@...ssion.com,
shuah@...nel.org,
brauner@...nel.org,
debug@...osinc.com,
guoren@...nel.org,
samitolvanen@...gle.com,
evan@...osinc.com,
xiao.w.wang@...el.com,
apatel@...tanamicro.com,
mchitale@...tanamicro.com,
waylingii@...il.com,
greentime.hu@...ive.com,
heiko@...ech.de,
jszhang@...nel.org,
shikemeng@...weicloud.com,
david@...hat.com,
charlie@...osinc.com,
panqinglin2020@...as.ac.cn,
willy@...radead.org,
vincent.chen@...ive.com,
andy.chiu@...ive.com,
gerg@...nel.org,
jeeheng.sia@...rfivetech.com,
mason.huo@...rfivetech.com,
ancientmodern4@...il.com,
mathis.salmen@...sal.de,
cuiyunhui@...edance.com,
bhe@...hat.com,
chenjiahao16@...wei.com,
ruscur@...sell.cc,
bgray@...ux.ibm.com,
alx@...nel.org,
baruch@...s.co.il,
zhangqing@...ngson.cn,
catalin.marinas@....com,
revest@...omium.org,
josh@...htriplett.org,
joey.gouly@....com,
shr@...kernel.io,
omosnace@...hat.com,
ojeda@...nel.org,
jhubbard@...dia.com,
linux-doc@...r.kernel.org,
linux-riscv@...ts.infradead.org,
linux-kernel@...r.kernel.org,
linux-mm@...ck.org,
linux-arch@...r.kernel.org,
linux-kselftest@...r.kernel.org
Subject: [RFC PATCH v1 20/28] riscv: Implements arch argnostic indirect branch tracking prctls
From: Deepak Gupta <debug@...osinc.com>
prctls implemented are PR_SET_INDIR_BR_LP_STATUS / PR_GET_INDIR_BR_LP_STATUS
and PR_LOCK_INDIR_BR_LP_STATUS.
Signed-off-by: Deepak Gupta <debug@...osinc.com>
---
arch/riscv/include/asm/usercfi.h | 17 +++++++-
arch/riscv/kernel/usercfi.c | 74 ++++++++++++++++++++++++++++++++
2 files changed, 90 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/usercfi.h b/arch/riscv/include/asm/usercfi.h
index 72bcfa773752..4bd10dcd48aa 100644
--- a/arch/riscv/include/asm/usercfi.h
+++ b/arch/riscv/include/asm/usercfi.h
@@ -16,7 +16,9 @@ struct kernel_clone_args;
struct cfi_status {
unsigned long ubcfi_en : 1; /* Enable for backward cfi. */
unsigned long ubcfi_locked : 1;
- unsigned long rsvd : ((sizeof(unsigned long)*8) - 2);
+ unsigned long ufcfi_en : 1; /* Enable for forward cfi. Note that ELP goes in sstatus */
+ unsigned long ufcfi_locked : 1;
+ unsigned long rsvd : ((sizeof(unsigned long)*8) - 4);
unsigned long user_shdw_stk; /* Current user shadow stack pointer */
unsigned long shdw_stk_base; /* Base address of shadow stack */
unsigned long shdw_stk_size; /* size of shadow stack */
@@ -29,6 +31,8 @@ void set_shstk_base(struct task_struct *task, unsigned long shstk_addr, unsigned
void set_active_shstk(struct task_struct *task, unsigned long shstk_addr);
bool is_shstk_enabled(struct task_struct *task);
bool is_shstk_locked(struct task_struct *task);
+bool is_indir_lp_enabled(struct task_struct *task);
+bool is_indir_lp_locked(struct task_struct *task);
#define PR_SHADOW_STACK_SUPPORTED_STATUS_MASK (PR_SHADOW_STACK_ENABLE)
@@ -66,6 +70,17 @@ static inline bool is_shstk_locked(struct task_struct *task)
return false;
}
+static inline bool is_indir_lp_enabled(struct task_struct *task)
+{
+ return false;
+}
+
+static inline bool is_indir_lp_locked(struct task_struct *task)
+
+{
+ return false;
+}
+
#endif /* CONFIG_RISCV_USER_CFI */
#endif /* __ASSEMBLY__ */
diff --git a/arch/riscv/kernel/usercfi.c b/arch/riscv/kernel/usercfi.c
index be3a071272d8..af8cc8f4616c 100644
--- a/arch/riscv/kernel/usercfi.c
+++ b/arch/riscv/kernel/usercfi.c
@@ -67,6 +67,30 @@ void set_shstk_lock(struct task_struct *task)
task->thread_info.user_cfi_state.ubcfi_locked = 1;
}
+bool is_indir_lp_enabled(struct task_struct *task)
+{
+ return task->thread_info.user_cfi_state.ufcfi_en ? true : false;
+}
+
+bool is_indir_lp_locked(struct task_struct *task)
+{
+ return task->thread_info.user_cfi_state.ufcfi_locked ? true : false;
+}
+
+void set_indir_lp_status(struct task_struct *task, bool enable)
+{
+ task->thread_info.user_cfi_state.ufcfi_en = enable ? 1 : 0;
+
+ if (enable)
+ task->thread_info.envcfg |= ENVCFG_LPE;
+ else
+ task->thread_info.envcfg &= ~ENVCFG_LPE;
+}
+
+void set_indir_lp_lock(struct task_struct *task)
+{
+ task->thread_info.user_cfi_state.ufcfi_locked = 1;
+}
/*
* If size is 0, then to be compatible with regular stack we want it to be as big as
* regular stack. Else PAGE_ALIGN it and return back
@@ -374,3 +398,53 @@ int arch_lock_shadow_stack_status(struct task_struct *task,
return 0;
}
+
+int arch_get_indir_br_lp_status(struct task_struct *t, unsigned long __user *status)
+{
+ unsigned long fcfi_status = 0;
+
+ if (!cpu_supports_indirect_br_lp_instr())
+ return -EINVAL;
+
+ /* indirect branch tracking is enabled on the task or not */
+ fcfi_status |= (is_indir_lp_enabled(t) ? PR_INDIR_BR_LP_ENABLE : 0);
+
+ return copy_to_user(status, &fcfi_status, sizeof(fcfi_status)) ? -EFAULT : 0;
+}
+
+int arch_set_indir_br_lp_status(struct task_struct *t, unsigned long status)
+{
+ bool enable_indir_lp = false;
+
+ if (!cpu_supports_indirect_br_lp_instr())
+ return -EINVAL;
+
+ /* indirect branch tracking is locked and further can't be modified by user */
+ if (is_indir_lp_locked(t))
+ return -EINVAL;
+
+ /* Reject unknown flags */
+ if (status & ~PR_INDIR_BR_LP_ENABLE)
+ return -EINVAL;
+
+ enable_indir_lp = (status & PR_INDIR_BR_LP_ENABLE) ? true : false;
+ set_indir_lp_status(t, enable_indir_lp);
+
+ return 0;
+}
+
+int arch_lock_indir_br_lp_status(struct task_struct *task,
+ unsigned long arg)
+{
+ /*
+ * If indirect branch tracking is not supported or not enabled on task,
+ * nothing to lock here
+ */
+ if (!cpu_supports_indirect_br_lp_instr() ||
+ !is_indir_lp_enabled(task))
+ return -EINVAL;
+
+ set_indir_lp_lock(task);
+
+ return 0;
+}
--
2.43.0
Powered by blists - more mailing lists