From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, KP Singh <kpsingh@kernel.org>,
Alexei Starovoitov <ast@kernel.org>,
Martin KaFai Lau <kafai@fb.com>
Subject: [PATCH 5.18 63/67] bpf: Fix usage of trace RCU in local storage.
Date: Fri, 3 Jun 2022 19:44:04 +0200 [thread overview]
Message-ID: <20220603173822.531727915@linuxfoundation.org> (raw)
In-Reply-To: <20220603173820.731531504@linuxfoundation.org>
From: KP Singh <kpsingh@kernel.org>
commit dcf456c9a095a6e71f53d6f6f004133ee851ee70 upstream.
bpf_{sk,task,inode}_storage_free() do not need to use
call_rcu_tasks_trace as no BPF program should be accessing the owner
as it's being destroyed. The only other reader at this point is
bpf_local_storage_map_free() which uses normal RCU.
The only path that needs trace RCU are:
* bpf_local_storage_{delete,update} helpers
* map_{delete,update}_elem() syscalls
Fixes: 0fe4b381a59e ("bpf: Allow bpf_local_storage to be used by sleepable programs")
Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220418155158.2865678-1-kpsingh@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/bpf_local_storage.h | 4 ++--
kernel/bpf/bpf_inode_storage.c | 4 ++--
kernel/bpf/bpf_local_storage.c | 29 +++++++++++++++++++----------
kernel/bpf/bpf_task_storage.c | 4 ++--
net/core/bpf_sk_storage.c | 6 +++---
5 files changed, 28 insertions(+), 19 deletions(-)
--- a/include/linux/bpf_local_storage.h
+++ b/include/linux/bpf_local_storage.h
@@ -143,9 +143,9 @@ void bpf_selem_link_storage_nolock(struc
bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_storage,
struct bpf_local_storage_elem *selem,
- bool uncharge_omem);
+ bool uncharge_omem, bool use_trace_rcu);
-void bpf_selem_unlink(struct bpf_local_storage_elem *selem);
+void bpf_selem_unlink(struct bpf_local_storage_elem *selem, bool use_trace_rcu);
void bpf_selem_link_map(struct bpf_local_storage_map *smap,
struct bpf_local_storage_elem *selem);
--- a/kernel/bpf/bpf_inode_storage.c
+++ b/kernel/bpf/bpf_inode_storage.c
@@ -90,7 +90,7 @@ void bpf_inode_storage_free(struct inode
*/
bpf_selem_unlink_map(selem);
free_inode_storage = bpf_selem_unlink_storage_nolock(
- local_storage, selem, false);
+ local_storage, selem, false, false);
}
raw_spin_unlock_bh(&local_storage->lock);
rcu_read_unlock();
@@ -149,7 +149,7 @@ static int inode_storage_delete(struct i
if (!sdata)
return -ENOENT;
- bpf_selem_unlink(SELEM(sdata));
+ bpf_selem_unlink(SELEM(sdata), true);
return 0;
}
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -106,7 +106,7 @@ static void bpf_selem_free_rcu(struct rc
*/
bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_storage,
struct bpf_local_storage_elem *selem,
- bool uncharge_mem)
+ bool uncharge_mem, bool use_trace_rcu)
{
struct bpf_local_storage_map *smap;
bool free_local_storage;
@@ -150,11 +150,16 @@ bool bpf_selem_unlink_storage_nolock(str
SDATA(selem))
RCU_INIT_POINTER(local_storage->cache[smap->cache_idx], NULL);
- call_rcu_tasks_trace(&selem->rcu, bpf_selem_free_rcu);
+ if (use_trace_rcu)
+ call_rcu_tasks_trace(&selem->rcu, bpf_selem_free_rcu);
+ else
+ kfree_rcu(selem, rcu);
+
return free_local_storage;
}
-static void __bpf_selem_unlink_storage(struct bpf_local_storage_elem *selem)
+static void __bpf_selem_unlink_storage(struct bpf_local_storage_elem *selem,
+ bool use_trace_rcu)
{
struct bpf_local_storage *local_storage;
bool free_local_storage = false;
@@ -169,12 +174,16 @@ static void __bpf_selem_unlink_storage(s
raw_spin_lock_irqsave(&local_storage->lock, flags);
if (likely(selem_linked_to_storage(selem)))
free_local_storage = bpf_selem_unlink_storage_nolock(
- local_storage, selem, true);
+ local_storage, selem, true, use_trace_rcu);
raw_spin_unlock_irqrestore(&local_storage->lock, flags);
- if (free_local_storage)
- call_rcu_tasks_trace(&local_storage->rcu,
+ if (free_local_storage) {
+ if (use_trace_rcu)
+ call_rcu_tasks_trace(&local_storage->rcu,
bpf_local_storage_free_rcu);
+ else
+ kfree_rcu(local_storage, rcu);
+ }
}
void bpf_selem_link_storage_nolock(struct bpf_local_storage *local_storage,
@@ -214,14 +223,14 @@ void bpf_selem_link_map(struct bpf_local
raw_spin_unlock_irqrestore(&b->lock, flags);
}
-void bpf_selem_unlink(struct bpf_local_storage_elem *selem)
+void bpf_selem_unlink(struct bpf_local_storage_elem *selem, bool use_trace_rcu)
{
/* Always unlink from map before unlinking from local_storage
* because selem will be freed after successfully unlinked from
* the local_storage.
*/
bpf_selem_unlink_map(selem);
- __bpf_selem_unlink_storage(selem);
+ __bpf_selem_unlink_storage(selem, use_trace_rcu);
}
struct bpf_local_storage_data *
@@ -466,7 +475,7 @@ bpf_local_storage_update(void *owner, st
if (old_sdata) {
bpf_selem_unlink_map(SELEM(old_sdata));
bpf_selem_unlink_storage_nolock(local_storage, SELEM(old_sdata),
- false);
+ false, true);
}
unlock:
@@ -548,7 +557,7 @@ void bpf_local_storage_map_free(struct b
migrate_disable();
__this_cpu_inc(*busy_counter);
}
- bpf_selem_unlink(selem);
+ bpf_selem_unlink(selem, false);
if (busy_counter) {
__this_cpu_dec(*busy_counter);
migrate_enable();
--- a/kernel/bpf/bpf_task_storage.c
+++ b/kernel/bpf/bpf_task_storage.c
@@ -102,7 +102,7 @@ void bpf_task_storage_free(struct task_s
*/
bpf_selem_unlink_map(selem);
free_task_storage = bpf_selem_unlink_storage_nolock(
- local_storage, selem, false);
+ local_storage, selem, false, false);
}
raw_spin_unlock_irqrestore(&local_storage->lock, flags);
bpf_task_storage_unlock();
@@ -192,7 +192,7 @@ static int task_storage_delete(struct ta
if (!sdata)
return -ENOENT;
- bpf_selem_unlink(SELEM(sdata));
+ bpf_selem_unlink(SELEM(sdata), true);
return 0;
}
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -40,7 +40,7 @@ static int bpf_sk_storage_del(struct soc
if (!sdata)
return -ENOENT;
- bpf_selem_unlink(SELEM(sdata));
+ bpf_selem_unlink(SELEM(sdata), true);
return 0;
}
@@ -75,8 +75,8 @@ void bpf_sk_storage_free(struct sock *sk
* sk_storage.
*/
bpf_selem_unlink_map(selem);
- free_sk_storage = bpf_selem_unlink_storage_nolock(sk_storage,
- selem, true);
+ free_sk_storage = bpf_selem_unlink_storage_nolock(
+ sk_storage, selem, true, false);
}
raw_spin_unlock_bh(&sk_storage->lock);
rcu_read_unlock();
next prev parent reply other threads:[~2022-06-03 18:18 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-03 17:43 [PATCH 5.18 00/67] 5.18.2-rc1 review Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 01/67] netfilter: nf_tables: disallow non-stateful expression in sets earlier Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 02/67] i2c: ismt: prevent memory corruption in ismt_access() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 03/67] assoc_array: Fix BUG_ON during garbage collect Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 04/67] pipe: make poll_usage boolean and annotate its access Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 05/67] pipe: Fix missing lock in pipe_resize_ring() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 06/67] net: ipa: compute proper aggregation limit Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 07/67] drm/i915: Fix -Wstringop-overflow warning in call to intel_read_wm_latency() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 08/67] exfat: check if cluster num is valid Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 09/67] exfat: fix referencing wrong parent directory information after renaming Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 10/67] netfilter: nft_limit: Clone packet limits cost value Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 11/67] netfilter: nf_tables: sanitize nft_set_desc_concat_parse() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 12/67] netfilter: nf_tables: hold mutex on netns pre_exit path Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 13/67] netfilter: nf_tables: double hook unregistration in netns path Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 14/67] netfilter: conntrack: re-fetch conntrack after insertion Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 15/67] KVM: PPC: Book3S HV: fix incorrect NULL check on list iterator Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 16/67] x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave) Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 17/67] x86/kvm: Alloc dummy async #PF token outside of raw spinlock Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 18/67] x86, kvm: use correct GFP flags for preemption disabled Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 19/67] x86/uaccess: Implement macros for CMPXCHG on user addresses Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 20/67] KVM: x86: Use __try_cmpxchg_user() to update guest PTE A/D bits Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 21/67] KVM: x86: Use __try_cmpxchg_user() to emulate atomic accesses Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 22/67] KVM: x86: fix typo in __try_cmpxchg_user causing non-atomicness Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 23/67] KVM: x86: avoid calling x86 emulator without a decoded instruction Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 24/67] KVM: x86: avoid loading a vCPU after .vm_destroy was called Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 25/67] KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 26/67] KVM: x86: Drop WARNs that assert a triple fault never "escapes" from L2 Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 27/67] KVM: x86/mmu: Dont rebuild page when the page is synced and no tlb flushing is required Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 28/67] KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 29/67] crypto: caam - fix i.MX6SX entropy delay value Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 30/67] crypto: ecrdsa - Fix incorrect use of vli_cmp Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 31/67] crypto: qat - rework the VF2PF interrupt handling logic Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 32/67] zsmalloc: fix races between asynchronous zspage free and page migration Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 33/67] tools/memory-model/README: Update klitmus7 compat table Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 34/67] ALSA: usb-audio: Workaround for clock setup on TEAC devices Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 35/67] ALSA: usb-audio: Add missing ep_idx in fixed EP quirks Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 36/67] ALSA: usb-audio: Configure sync endpoints before data Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 37/67] Bluetooth: hci_qca: Use del_timer_sync() before freeing Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 38/67] ARM: dts: s5pv210: Correct interrupt name for bluetooth in Aries Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 39/67] dm integrity: fix error code in dm_integrity_ctr() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 40/67] dm crypt: make printing of the key constant-time Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 41/67] dm stats: add cond_resched when looping over entries Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 42/67] dm verity: set DM_TARGET_IMMUTABLE feature flag Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 43/67] raid5: introduce MD_BROKEN Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 44/67] fs/ntfs3: validate BOOT sectors_per_clusters Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 45/67] HID: multitouch: Add support for Google Whiskers Touchpad Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 46/67] HID: multitouch: add quirks to enable Lenovo X12 trackpoint Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 47/67] x86/sgx: Disconnect backing page references from dirty status Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 48/67] x86/sgx: Mark PCMD page as dirty when modifying contents Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 49/67] x86/sgx: Obtain backing storage page with enclave mutex held Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 50/67] x86/sgx: Fix race between reclaimer and page fault handler Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 51/67] x86/sgx: Ensure no data in PCMD page after truncate Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 52/67] media: i2c: imx412: Fix reset GPIO polarity Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 53/67] media: i2c: imx412: Fix power_off ordering Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 54/67] tpm: Fix buffer access in tpm2_get_tpm_pt() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 55/67] tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe() Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 56/67] docs: submitting-patches: Fix crossref to The canonical patch format Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 57/67] NFS: Memory allocation failures are not server fatal errors Greg Kroah-Hartman
2022-06-03 17:43 ` [PATCH 5.18 58/67] NFSD: Fix possible sleep during nfsd4_release_lockowner() Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 59/67] bpf: Fill new bpf_prog_pack with illegal instructions Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 60/67] bpf: Fix potential array overflow in bpf_trampoline_get_progs() Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 61/67] bpf: Fix combination of jit blinding and pointers to bpf subprogs Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 62/67] bpf: Enlarge offset check value to INT_MAX in bpf_skb_{load,store}_bytes Greg Kroah-Hartman
2022-06-03 17:44 ` Greg Kroah-Hartman [this message]
2022-06-03 17:44 ` [PATCH 5.18 64/67] bpf: Fix excessive memory allocation in stack_map_alloc() Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 65/67] bpf: Reject writes for PTR_TO_MAP_KEY in check_helper_mem_access Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 66/67] bpf: Check PTR_TO_MEM | MEM_RDONLY " Greg Kroah-Hartman
2022-06-03 17:44 ` [PATCH 5.18 67/67] bpf: Do write access check for kfunc and global func Greg Kroah-Hartman
2022-06-03 23:00 ` [PATCH 5.18 00/67] 5.18.2-rc1 review Justin Forbes
2022-06-04 6:25 ` Ron Economos
2022-06-04 16:45 ` Naresh Kamboju
2022-06-04 18:56 ` Guenter Roeck
2022-06-05 2:28 ` Rudi Heitbaum
2022-06-05 7:02 ` Bagas Sanjaya
2022-06-05 7:38 ` Greg Kroah-Hartman
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