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authorVignesh Raghavendra <vigneshr@ti.com>2022-06-04 13:32:19 +0530
committerVignesh Raghavendra <vigneshr@ti.com>2022-06-04 13:32:19 +0530
commitde63dee020025075c6962f6b536797bc3af3e970 (patch)
tree89173487fdaabb029dfb1b0a6b68484ec3edef35 /kernel/bpf
parentcc13f3f3acad08038b76f5f26f66151c136d1eaf (diff)
parente61686bb77c441d8e5f10dc063e2cea799e4aae6 (diff)
Merge tag 'v5.10.115' of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux into ti-linux-5.10.y
This is the 5.10.115 stable release * tag 'v5.10.115' of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux: (1162 commits) Linux 5.10.115 mmc: rtsx: add 74 Clocks in power on flow PCI: aardvark: Fix reading MSI interrupt number PCI: aardvark: Clear all MSIs at setup dm: interlock pending dm_io and dm_wait_for_bios_completion block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern rcu: Apply callbacks processing time limit only on softirq rcu: Fix callbacks processing time limit retaining cond_resched() KVM: LAPIC: Enable timer posted-interrupt only when mwait/hlt is advertised KVM: x86/mmu: avoid NULL-pointer dereference on page freeing bugs KVM: x86: Do not change ICR on write to APIC_SELF_IPI x86/kvm: Preserve BSP MSR_KVM_POLL_CONTROL across suspend/resume net/mlx5: Fix slab-out-of-bounds while reading resource dump menu kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU net: igmp: respect RCU rules in ip_mc_source() and ip_mc_msfilter() btrfs: always log symlinks in full mode smsc911x: allow using IRQ0 selftests: ocelot: tc_flower_chains: specify conform-exceed action for policer bnxt_en: Fix unnecessary dropping of RX packets bnxt_en: Fix possible bnxt_open() failure caused by wrong RFS flag ... Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Diffstat (limited to 'kernel/bpf')
-rw-r--r--kernel/bpf/stackmap.c56
1 files changed, 24 insertions, 32 deletions
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 56cd7e6589ff..4575d2d60cb1 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -358,7 +358,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs,
}
static struct perf_callchain_entry *
-get_callchain_entry_for_task(struct task_struct *task, u32 init_nr)
+get_callchain_entry_for_task(struct task_struct *task, u32 max_depth)
{
#ifdef CONFIG_STACKTRACE
struct perf_callchain_entry *entry;
@@ -369,9 +369,8 @@ get_callchain_entry_for_task(struct task_struct *task, u32 init_nr)
if (!entry)
return NULL;
- entry->nr = init_nr +
- stack_trace_save_tsk(task, (unsigned long *)(entry->ip + init_nr),
- sysctl_perf_event_max_stack - init_nr, 0);
+ entry->nr = stack_trace_save_tsk(task, (unsigned long *)entry->ip,
+ max_depth, 0);
/* stack_trace_save_tsk() works on unsigned long array, while
* perf_callchain_entry uses u64 array. For 32-bit systems, it is
@@ -383,7 +382,7 @@ get_callchain_entry_for_task(struct task_struct *task, u32 init_nr)
int i;
/* copy data from the end to avoid using extra buffer */
- for (i = entry->nr - 1; i >= (int)init_nr; i--)
+ for (i = entry->nr - 1; i >= 0; i--)
to[i] = (u64)(from[i]);
}
@@ -400,27 +399,19 @@ static long __bpf_get_stackid(struct bpf_map *map,
{
struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
struct stack_map_bucket *bucket, *new_bucket, *old_bucket;
- u32 max_depth = map->value_size / stack_map_data_size(map);
- /* stack_map_alloc() checks that max_depth <= sysctl_perf_event_max_stack */
- u32 init_nr = sysctl_perf_event_max_stack - max_depth;
u32 skip = flags & BPF_F_SKIP_FIELD_MASK;
u32 hash, id, trace_nr, trace_len;
bool user = flags & BPF_F_USER_STACK;
u64 *ips;
bool hash_matches;
- /* get_perf_callchain() guarantees that trace->nr >= init_nr
- * and trace-nr <= sysctl_perf_event_max_stack, so trace_nr <= max_depth
- */
- trace_nr = trace->nr - init_nr;
-
- if (trace_nr <= skip)
+ if (trace->nr <= skip)
/* skipping more than usable stack trace */
return -EFAULT;
- trace_nr -= skip;
+ trace_nr = trace->nr - skip;
trace_len = trace_nr * sizeof(u64);
- ips = trace->ip + skip + init_nr;
+ ips = trace->ip + skip;
hash = jhash2((u32 *)ips, trace_len / sizeof(u32), 0);
id = hash & (smap->n_buckets - 1);
bucket = READ_ONCE(smap->buckets[id]);
@@ -477,8 +468,7 @@ BPF_CALL_3(bpf_get_stackid, struct pt_regs *, regs, struct bpf_map *, map,
u64, flags)
{
u32 max_depth = map->value_size / stack_map_data_size(map);
- /* stack_map_alloc() checks that max_depth <= sysctl_perf_event_max_stack */
- u32 init_nr = sysctl_perf_event_max_stack - max_depth;
+ u32 skip = flags & BPF_F_SKIP_FIELD_MASK;
bool user = flags & BPF_F_USER_STACK;
struct perf_callchain_entry *trace;
bool kernel = !user;
@@ -487,8 +477,12 @@ BPF_CALL_3(bpf_get_stackid, struct pt_regs *, regs, struct bpf_map *, map,
BPF_F_FAST_STACK_CMP | BPF_F_REUSE_STACKID)))
return -EINVAL;
- trace = get_perf_callchain(regs, init_nr, kernel, user,
- sysctl_perf_event_max_stack, false, false);
+ max_depth += skip;
+ if (max_depth > sysctl_perf_event_max_stack)
+ max_depth = sysctl_perf_event_max_stack;
+
+ trace = get_perf_callchain(regs, 0, kernel, user, max_depth,
+ false, false);
if (unlikely(!trace))
/* couldn't fetch the stack trace */
@@ -579,7 +573,7 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task,
struct perf_callchain_entry *trace_in,
void *buf, u32 size, u64 flags)
{
- u32 init_nr, trace_nr, copy_len, elem_size, num_elem;
+ u32 trace_nr, copy_len, elem_size, num_elem, max_depth;
bool user_build_id = flags & BPF_F_USER_BUILD_ID;
u32 skip = flags & BPF_F_SKIP_FIELD_MASK;
bool user = flags & BPF_F_USER_STACK;
@@ -604,30 +598,28 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task,
goto err_fault;
num_elem = size / elem_size;
- if (sysctl_perf_event_max_stack < num_elem)
- init_nr = 0;
- else
- init_nr = sysctl_perf_event_max_stack - num_elem;
+ max_depth = num_elem + skip;
+ if (sysctl_perf_event_max_stack < max_depth)
+ max_depth = sysctl_perf_event_max_stack;
if (trace_in)
trace = trace_in;
else if (kernel && task)
- trace = get_callchain_entry_for_task(task, init_nr);
+ trace = get_callchain_entry_for_task(task, max_depth);
else
- trace = get_perf_callchain(regs, init_nr, kernel, user,
- sysctl_perf_event_max_stack,
+ trace = get_perf_callchain(regs, 0, kernel, user, max_depth,
false, false);
if (unlikely(!trace))
goto err_fault;
- trace_nr = trace->nr - init_nr;
- if (trace_nr < skip)
+ if (trace->nr < skip)
goto err_fault;
- trace_nr -= skip;
+ trace_nr = trace->nr - skip;
trace_nr = (trace_nr <= num_elem) ? trace_nr : num_elem;
copy_len = trace_nr * elem_size;
- ips = trace->ip + skip + init_nr;
+
+ ips = trace->ip + skip;
if (user && user_build_id)
stack_map_get_build_id_offset(buf, ips, trace_nr, user);
else