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Diffstat (limited to 'kernel')
-rw-r--r--kernel/bpf/core.c12
-rw-r--r--kernel/bpf/verifier.c5
-rw-r--r--kernel/ptrace.c20
-rw-r--r--kernel/trace/ring_buffer.c11
-rw-r--r--kernel/trace/trace_functions_graph.c8
5 files changed, 41 insertions, 15 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index d6594e457a25..71a9e5be6592 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -357,8 +357,8 @@ select_insn:
ALU64_MOD_X:
if (unlikely(SRC == 0))
return 0;
- tmp = DST;
- DST = do_div(tmp, SRC);
+ div64_u64_rem(DST, SRC, &tmp);
+ DST = tmp;
CONT;
ALU_MOD_X:
if (unlikely(SRC == 0))
@@ -367,8 +367,8 @@ select_insn:
DST = do_div(tmp, (u32) SRC);
CONT;
ALU64_MOD_K:
- tmp = DST;
- DST = do_div(tmp, IMM);
+ div64_u64_rem(DST, IMM, &tmp);
+ DST = tmp;
CONT;
ALU_MOD_K:
tmp = (u32) DST;
@@ -377,7 +377,7 @@ select_insn:
ALU64_DIV_X:
if (unlikely(SRC == 0))
return 0;
- do_div(DST, SRC);
+ DST = div64_u64(DST, SRC);
CONT;
ALU_DIV_X:
if (unlikely(SRC == 0))
@@ -387,7 +387,7 @@ select_insn:
DST = (u32) tmp;
CONT;
ALU64_DIV_K:
- do_div(DST, IMM);
+ DST = div64_u64(DST, IMM);
CONT;
ALU_DIV_K:
tmp = (u32) DST;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d8dcc80472c1..055ae6ac0280 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -763,7 +763,7 @@ static int check_func_arg(struct verifier_env *env, u32 regno,
enum bpf_reg_type expected_type;
int err = 0;
- if (arg_type == ARG_ANYTHING)
+ if (arg_type == ARG_DONTCARE)
return 0;
if (reg->type == NOT_INIT) {
@@ -771,6 +771,9 @@ static int check_func_arg(struct verifier_env *env, u32 regno,
return -EACCES;
}
+ if (arg_type == ARG_ANYTHING)
+ return 0;
+
if (arg_type == ARG_PTR_TO_STACK || arg_type == ARG_PTR_TO_MAP_KEY ||
arg_type == ARG_PTR_TO_MAP_VALUE) {
expected_type = PTR_TO_STACK;
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 54e75226c2c4..dcd968232d42 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -714,6 +714,8 @@ static int ptrace_peek_siginfo(struct task_struct *child,
static int ptrace_resume(struct task_struct *child, long request,
unsigned long data)
{
+ bool need_siglock;
+
if (!valid_signal(data))
return -EIO;
@@ -741,8 +743,26 @@ static int ptrace_resume(struct task_struct *child, long request,
user_disable_single_step(child);
}
+ /*
+ * Change ->exit_code and ->state under siglock to avoid the race
+ * with wait_task_stopped() in between; a non-zero ->exit_code will
+ * wrongly look like another report from tracee.
+ *
+ * Note that we need siglock even if ->exit_code == data and/or this
+ * status was not reported yet, the new status must not be cleared by
+ * wait_task_stopped() after resume.
+ *
+ * If data == 0 we do not care if wait_task_stopped() reports the old
+ * status and clears the code too; this can't race with the tracee, it
+ * takes siglock after resume.
+ */
+ need_siglock = data && !thread_group_empty(current);
+ if (need_siglock)
+ spin_lock_irq(&child->sighand->siglock);
child->exit_code = data;
wake_up_state(child, __TASK_TRACED);
+ if (need_siglock)
+ spin_unlock_irq(&child->sighand->siglock);
return 0;
}
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index f4fbbfcdf399..0fc5cfedcc8c 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2684,7 +2684,7 @@ static DEFINE_PER_CPU(unsigned int, current_context);
static __always_inline int trace_recursive_lock(void)
{
- unsigned int val = this_cpu_read(current_context);
+ unsigned int val = __this_cpu_read(current_context);
int bit;
if (in_interrupt()) {
@@ -2701,18 +2701,17 @@ static __always_inline int trace_recursive_lock(void)
return 1;
val |= (1 << bit);
- this_cpu_write(current_context, val);
+ __this_cpu_write(current_context, val);
return 0;
}
static __always_inline void trace_recursive_unlock(void)
{
- unsigned int val = this_cpu_read(current_context);
+ unsigned int val = __this_cpu_read(current_context);
- val--;
- val &= this_cpu_read(current_context);
- this_cpu_write(current_context, val);
+ val &= val & (val - 1);
+ __this_cpu_write(current_context, val);
}
#else
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index f0a0c982cde3..2964333687dc 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -1462,15 +1462,19 @@ void graph_trace_open(struct trace_iterator *iter)
{
/* pid and depth on the last trace processed */
struct fgraph_data *data;
+ gfp_t gfpflags;
int cpu;
iter->private = NULL;
- data = kzalloc(sizeof(*data), GFP_KERNEL);
+ /* We can be called in atomic context via ftrace_dump() */
+ gfpflags = (in_atomic() || irqs_disabled()) ? GFP_ATOMIC : GFP_KERNEL;
+
+ data = kzalloc(sizeof(*data), gfpflags);
if (!data)
goto out_err;
- data->cpu_data = alloc_percpu(struct fgraph_cpu_data);
+ data->cpu_data = alloc_percpu_gfp(struct fgraph_cpu_data, gfpflags);
if (!data->cpu_data)
goto out_err_free;