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-rw-r--r--kernel/bpf/verifier.c23
-rw-r--r--kernel/cgroup/cgroup.c10
-rw-r--r--kernel/events/hw_breakpoint.c4
-rw-r--r--kernel/fork.c10
-rw-r--r--kernel/irq/resend.c2
-rw-r--r--kernel/sched/core.c78
-rw-r--r--kernel/sched/fair.c5
7 files changed, 81 insertions, 51 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b5c14c9d7b98..c36a719fee6d 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1772,16 +1772,21 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno,
bitmap_from_u64(mask, stack_mask);
for_each_set_bit(i, mask, 64) {
if (i >= func->allocated_stack / BPF_REG_SIZE) {
- /* This can happen if backtracking
- * is propagating stack precision where
- * caller has larger stack frame
- * than callee, but backtrack_insn() should
- * have returned -ENOTSUPP.
+ /* the sequence of instructions:
+ * 2: (bf) r3 = r10
+ * 3: (7b) *(u64 *)(r3 -8) = r0
+ * 4: (79) r4 = *(u64 *)(r10 -8)
+ * doesn't contain jmps. It's backtracked
+ * as a single block.
+ * During backtracking insn 3 is not recognized as
+ * stack access, so at the end of backtracking
+ * stack slot fp-8 is still marked in stack_mask.
+ * However the parent state may not have accessed
+ * fp-8 and it's "unallocated" stack space.
+ * In such case fallback to conservative.
*/
- verbose(env, "BUG spi %d stack_size %d\n",
- i, func->allocated_stack);
- WARN_ONCE(1, "verifier backtracking bug");
- return -EFAULT;
+ mark_all_scalars_precise(env, st);
+ return 0;
}
if (func->stack[i].slot_type[0] != STACK_SPILL) {
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 753afbca549f..8be1da1ebd9a 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -5255,8 +5255,16 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
* if the parent has to be frozen, the child has too.
*/
cgrp->freezer.e_freeze = parent->freezer.e_freeze;
- if (cgrp->freezer.e_freeze)
+ if (cgrp->freezer.e_freeze) {
+ /*
+ * Set the CGRP_FREEZE flag, so when a process will be
+ * attached to the child cgroup, it will become frozen.
+ * At this point the new cgroup is unpopulated, so we can
+ * consider it frozen immediately.
+ */
+ set_bit(CGRP_FREEZE, &cgrp->flags);
set_bit(CGRP_FROZEN, &cgrp->flags);
+ }
spin_lock_irq(&css_set_lock);
for (tcgrp = cgrp; tcgrp; tcgrp = cgroup_parent(tcgrp)) {
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index c5cd852fe86b..3cc8416ec844 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -413,7 +413,7 @@ static int hw_breakpoint_parse(struct perf_event *bp,
int register_perf_hw_breakpoint(struct perf_event *bp)
{
- struct arch_hw_breakpoint hw;
+ struct arch_hw_breakpoint hw = { };
int err;
err = reserve_bp_slot(bp);
@@ -461,7 +461,7 @@ int
modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr,
bool check)
{
- struct arch_hw_breakpoint hw;
+ struct arch_hw_breakpoint hw = { };
int err;
err = hw_breakpoint_parse(bp, attr, &hw);
diff --git a/kernel/fork.c b/kernel/fork.c
index 2852d0e76ea3..541fd805fb88 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2338,6 +2338,8 @@ struct mm_struct *copy_init_mm(void)
*
* It copies the process, and if successful kick-starts
* it and waits for it to finish using the VM if required.
+ *
+ * args->exit_signal is expected to be checked for sanity by the caller.
*/
long _do_fork(struct kernel_clone_args *args)
{
@@ -2562,6 +2564,14 @@ noinline static int copy_clone_args_from_user(struct kernel_clone_args *kargs,
if (copy_from_user(&args, uargs, size))
return -EFAULT;
+ /*
+ * Verify that higher 32bits of exit_signal are unset and that
+ * it is a valid signal
+ */
+ if (unlikely((args.exit_signal & ~((u64)CSIGNAL)) ||
+ !valid_signal(args.exit_signal)))
+ return -EINVAL;
+
*kargs = (struct kernel_clone_args){
.flags = args.flags,
.pidfd = u64_to_user_ptr(args.pidfd),
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 95414ad3506a..98c04ca5fa43 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -36,6 +36,8 @@ static void resend_irqs(unsigned long arg)
irq = find_first_bit(irqs_resend, nr_irqs);
clear_bit(irq, irqs_resend);
desc = irq_to_desc(irq);
+ if (!desc)
+ continue;
local_irq_disable();
desc->handle_irq(desc);
local_irq_enable();
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 010d578118d6..df9f1fe5689b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5105,37 +5105,40 @@ out_unlock:
return retval;
}
-static int sched_read_attr(struct sched_attr __user *uattr,
- struct sched_attr *attr,
- unsigned int usize)
+/*
+ * Copy the kernel size attribute structure (which might be larger
+ * than what user-space knows about) to user-space.
+ *
+ * Note that all cases are valid: user-space buffer can be larger or
+ * smaller than the kernel-space buffer. The usual case is that both
+ * have the same size.
+ */
+static int
+sched_attr_copy_to_user(struct sched_attr __user *uattr,
+ struct sched_attr *kattr,
+ unsigned int usize)
{
- int ret;
+ unsigned int ksize = sizeof(*kattr);
if (!access_ok(uattr, usize))
return -EFAULT;
/*
- * If we're handed a smaller struct than we know of,
- * ensure all the unknown bits are 0 - i.e. old
- * user-space does not get uncomplete information.
+ * sched_getattr() ABI forwards and backwards compatibility:
+ *
+ * If usize == ksize then we just copy everything to user-space and all is good.
+ *
+ * If usize < ksize then we only copy as much as user-space has space for,
+ * this keeps ABI compatibility as well. We skip the rest.
+ *
+ * If usize > ksize then user-space is using a newer version of the ABI,
+ * which part the kernel doesn't know about. Just ignore it - tooling can
+ * detect the kernel's knowledge of attributes from the attr->size value
+ * which is set to ksize in this case.
*/
- if (usize < sizeof(*attr)) {
- unsigned char *addr;
- unsigned char *end;
+ kattr->size = min(usize, ksize);
- addr = (void *)attr + usize;
- end = (void *)attr + sizeof(*attr);
-
- for (; addr < end; addr++) {
- if (*addr)
- return -EFBIG;
- }
-
- attr->size = usize;
- }
-
- ret = copy_to_user(uattr, attr, attr->size);
- if (ret)
+ if (copy_to_user(uattr, kattr, kattr->size))
return -EFAULT;
return 0;
@@ -5145,20 +5148,18 @@ static int sched_read_attr(struct sched_attr __user *uattr,
* sys_sched_getattr - similar to sched_getparam, but with sched_attr
* @pid: the pid in question.
* @uattr: structure containing the extended parameters.
- * @size: sizeof(attr) for fwd/bwd comp.
+ * @usize: sizeof(attr) that user-space knows about, for forwards and backwards compatibility.
* @flags: for future extension.
*/
SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
- unsigned int, size, unsigned int, flags)
+ unsigned int, usize, unsigned int, flags)
{
- struct sched_attr attr = {
- .size = sizeof(struct sched_attr),
- };
+ struct sched_attr kattr = { };
struct task_struct *p;
int retval;
- if (!uattr || pid < 0 || size > PAGE_SIZE ||
- size < SCHED_ATTR_SIZE_VER0 || flags)
+ if (!uattr || pid < 0 || usize > PAGE_SIZE ||
+ usize < SCHED_ATTR_SIZE_VER0 || flags)
return -EINVAL;
rcu_read_lock();
@@ -5171,25 +5172,24 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
if (retval)
goto out_unlock;
- attr.sched_policy = p->policy;
+ kattr.sched_policy = p->policy;
if (p->sched_reset_on_fork)
- attr.sched_flags |= SCHED_FLAG_RESET_ON_FORK;
+ kattr.sched_flags |= SCHED_FLAG_RESET_ON_FORK;
if (task_has_dl_policy(p))
- __getparam_dl(p, &attr);
+ __getparam_dl(p, &kattr);
else if (task_has_rt_policy(p))
- attr.sched_priority = p->rt_priority;
+ kattr.sched_priority = p->rt_priority;
else
- attr.sched_nice = task_nice(p);
+ kattr.sched_nice = task_nice(p);
#ifdef CONFIG_UCLAMP_TASK
- attr.sched_util_min = p->uclamp_req[UCLAMP_MIN].value;
- attr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value;
+ kattr.sched_util_min = p->uclamp_req[UCLAMP_MIN].value;
+ kattr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value;
#endif
rcu_read_unlock();
- retval = sched_read_attr(uattr, &attr, size);
- return retval;
+ return sched_attr_copy_to_user(uattr, &kattr, usize);
out_unlock:
rcu_read_unlock();
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index bc9cfeaac8bd..500f5db0de0b 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4470,6 +4470,8 @@ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec)
if (likely(cfs_rq->runtime_remaining > 0))
return;
+ if (cfs_rq->throttled)
+ return;
/*
* if we're unable to extend our runtime we resched so that the active
* hierarchy can be throttled
@@ -4673,6 +4675,9 @@ static u64 distribute_cfs_runtime(struct cfs_bandwidth *cfs_b,
if (!cfs_rq_throttled(cfs_rq))
goto next;
+ /* By the above check, this should never be true */
+ SCHED_WARN_ON(cfs_rq->runtime_remaining > 0);
+
runtime = -cfs_rq->runtime_remaining + 1;
if (runtime > remaining)
runtime = remaining;