From: Sasha Levin <sashal@kernel•org>
To: linux-kernel@vger•kernel.org, stable@vger•kernel.org
Cc: Martynas Pumputis <m@lambda•lt>,
Andrii Nakryiko <andrii@kernel•org>,
John Fastabend <john.fastabend@gmail•com>,
Sasha Levin <sashal@kernel•org>,
netdev@vger•kernel.org, bpf@vger•kernel.org
Subject: [PATCH AUTOSEL 5.13 011/219] libbpf: Fix reuse of pinned map on older kernel
Date: Thu, 9 Sep 2021 07:43:07 -0400 [thread overview]
Message-ID: <20210909114635.143983-11-sashal@kernel.org> (raw)
In-Reply-To: <20210909114635.143983-1-sashal@kernel.org>
From: Martynas Pumputis <m@lambda•lt>
[ Upstream commit 97eb31384af943d6b97eb5947262cee4ef25cb87 ]
When loading a BPF program with a pinned map, the loader checks whether
the pinned map can be reused, i.e. their properties match. To derive
such of the pinned map, the loader invokes BPF_OBJ_GET_INFO_BY_FD and
then does the comparison.
Unfortunately, on < 4.12 kernels the BPF_OBJ_GET_INFO_BY_FD is not
available, so loading the program fails with the following error:
libbpf: failed to get map info for map FD 5: Invalid argument
libbpf: couldn't reuse pinned map at
'/sys/fs/bpf/tc/globals/cilium_call_policy': parameter
mismatch"
libbpf: map 'cilium_call_policy': error reusing pinned map
libbpf: map 'cilium_call_policy': failed to create:
Invalid argument(-22)
libbpf: failed to load object 'bpf_overlay.o'
To fix this, fallback to derivation of the map properties via
/proc/$PID/fdinfo/$MAP_FD if BPF_OBJ_GET_INFO_BY_FD fails with EINVAL,
which can be used as an indicator that the kernel doesn't support
the latter.
Signed-off-by: Martynas Pumputis <m@lambda•lt>
Signed-off-by: Andrii Nakryiko <andrii@kernel•org>
Acked-by: John Fastabend <john.fastabend@gmail•com>
Link: https://lore.kernel.org/bpf/20210712125552.58705-1-m@lambda.lt
Signed-off-by: Sasha Levin <sashal@kernel•org>
---
tools/lib/bpf/libbpf.c | 48 +++++++++++++++++++++++++++++++++++++++---
1 file changed, 45 insertions(+), 3 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index c41d9b2b59ac..164ee8b2847b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3844,6 +3844,42 @@ static int bpf_map_find_btf_info(struct bpf_object *obj, struct bpf_map *map)
return 0;
}
+static int bpf_get_map_info_from_fdinfo(int fd, struct bpf_map_info *info)
+{
+ char file[PATH_MAX], buff[4096];
+ FILE *fp;
+ __u32 val;
+ int err;
+
+ snprintf(file, sizeof(file), "/proc/%d/fdinfo/%d", getpid(), fd);
+ memset(info, 0, sizeof(*info));
+
+ fp = fopen(file, "r");
+ if (!fp) {
+ err = -errno;
+ pr_warn("failed to open %s: %d. No procfs support?\n", file,
+ err);
+ return err;
+ }
+
+ while (fgets(buff, sizeof(buff), fp)) {
+ if (sscanf(buff, "map_type:\t%u", &val) == 1)
+ info->type = val;
+ else if (sscanf(buff, "key_size:\t%u", &val) == 1)
+ info->key_size = val;
+ else if (sscanf(buff, "value_size:\t%u", &val) == 1)
+ info->value_size = val;
+ else if (sscanf(buff, "max_entries:\t%u", &val) == 1)
+ info->max_entries = val;
+ else if (sscanf(buff, "map_flags:\t%i", &val) == 1)
+ info->map_flags = val;
+ }
+
+ fclose(fp);
+
+ return 0;
+}
+
int bpf_map__reuse_fd(struct bpf_map *map, int fd)
{
struct bpf_map_info info = {};
@@ -3852,6 +3888,8 @@ int bpf_map__reuse_fd(struct bpf_map *map, int fd)
char *new_name;
err = bpf_obj_get_info_by_fd(fd, &info, &len);
+ if (err && errno == EINVAL)
+ err = bpf_get_map_info_from_fdinfo(fd, &info);
if (err)
return err;
@@ -4318,12 +4356,16 @@ static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd)
struct bpf_map_info map_info = {};
char msg[STRERR_BUFSIZE];
__u32 map_info_len;
+ int err;
map_info_len = sizeof(map_info);
- if (bpf_obj_get_info_by_fd(map_fd, &map_info, &map_info_len)) {
- pr_warn("failed to get map info for map FD %d: %s\n",
- map_fd, libbpf_strerror_r(errno, msg, sizeof(msg)));
+ err = bpf_obj_get_info_by_fd(map_fd, &map_info, &map_info_len);
+ if (err && errno == EINVAL)
+ err = bpf_get_map_info_from_fdinfo(map_fd, &map_info);
+ if (err) {
+ pr_warn("failed to get map info for map FD %d: %s\n", map_fd,
+ libbpf_strerror_r(errno, msg, sizeof(msg)));
return false;
}
--
2.30.2
next parent reply other threads:[~2021-09-09 12:06 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210909114635.143983-1-sashal@kernel.org>
2021-09-09 11:43 ` Sasha Levin [this message]
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 016/219] tipc: keep the skb in rcv queue until the whole data is read Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 017/219] net: phy: Fix data type in DP83822 dp8382x_disable_wol() Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 019/219] iavf: do not override the adapter state in the watchdog task Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 020/219] iavf: fix locking of critical sections Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 024/219] netlink: Deal with ESRCH error in nlmsg_notify() Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 025/219] net: ipa: fix IPA v4.11 interconnect data Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 031/219] igc: Check if num of q_vectors is smaller than max before array access Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 049/219] nfp: fix return statement in nfp_net_parse_meta() Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 052/219] ethtool: improve compat ioctl handling Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 055/219] bpf/tests: Fix copy-and-paste error in double word test Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 056/219] bpf/tests: Do not PASS tests without actually testing the result Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 062/219] net: ipa: fix ipa_cmd_table_valid() Sasha Levin
2021-09-09 11:43 ` [PATCH AUTOSEL 5.13 063/219] ipv4: ip_output.c: Fix out-of-bounds warning in ip_copy_addrs() Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 064/219] flow_dissector: Fix out-of-bounds warnings Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 072/219] samples: bpf: Fix tracex7 error raised on the missing argument Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 073/219] libbpf: Fix race when pinning maps in parallel Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 077/219] Bluetooth: skip invalid hci_sync_conn_complete_evt Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 082/219] netfilter: nft_compat: use nfnetlink_unicast() Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 083/219] bonding: 3ad: fix the concurrency between __bond_release_one() and bond_3ad_state_machine_handler() Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 087/219] bpf: Fix off-by-one in tail call count limiting Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 089/219] Bluetooth: Fix not generating RPA when required Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 090/219] dpaa2-switch: do not enable the DPSW at probe time Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 100/219] net: ipa: fix IPA v4.9 interconnects Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 111/219] net: ethernet: stmmac: Do not use unreachable() in ipq806x_gmac_probe() Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 120/219] selftests/bpf: Fix xdp_tx.c prog section name Sasha Levin
2021-09-09 11:44 ` [PATCH AUTOSEL 5.13 123/219] Bluetooth: schedule SCO timeouts with delayed_work Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 124/219] Bluetooth: avoid circular locks in sco_sock_connect Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 128/219] net/mlx5: Fix variable type to match 64bit Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 131/219] mac80211: Fix monitor MTU limit so that A-MSDUs get through Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 142/219] Bluetooth: Fix handling of LE Enhanced Connection Complete Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 146/219] tcp: enable data-less, empty-cookie SYN with TFO_SERVER_COOKIE_NOT_REQD Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 148/219] rpc: fix gss_svc_init cleanup on failure Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 149/219] iavf: use mutexes for locking of critical sections Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 150/219] selftests/bpf: Correctly display subtest skip status Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 151/219] selftests/bpf: Fix flaky send_signal test Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 154/219] selftests: nci: Fix the code for next nlattr offset Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 155/219] selftests: nci: Fix the wrong condition Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 156/219] net: Fix offloading indirect devices dependency on qdisc order creation Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 163/219] rtl8xxxu: Fix the handling of TX A-MPDU aggregation Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 164/219] rtw88: use read_poll_timeout instead of fixed sleep Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 165/219] rtw88: wow: build wow function only if CONFIG_PM is on Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 166/219] rtw88: wow: fix size access error of probe request Sasha Levin
2021-09-09 11:45 ` [PATCH AUTOSEL 5.13 167/219] octeontx2-pf: Fix NIX1_RX interface backpressure Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 184/219] mptcp: fix ADD_ADDR and RM_ADDR maybe flush addr_signal each other Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 185/219] selftests/bpf: Enlarge select() timeout for test_maps Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 201/219] iwlwifi: pcie: free RBs during configure Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 202/219] iwlwifi: mvm: Do not use full SSIDs in 6GHz scan Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 203/219] iwlwifi: mvm: fix a memory leak in iwl_mvm_mac_ctxt_beacon_changed Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 204/219] iwlwifi: mvm: avoid static queue number aliasing Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 205/219] iwlwifi: mvm: Fix umac scan request probe parameters Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 206/219] iwlwifi: mvm: fix access to BSS elements Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 207/219] iwlwifi: fw: correctly limit to monitor dump Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 208/219] iwlwifi: mvm: Fix scan channel flags settings Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 209/219] net/mlx5: DR, fix a potential use-after-free bug Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 210/219] net/mlx5: DR, Enable QP retransmission Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 212/219] selftests/bpf: Fix potential unreleased lock Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 213/219] wcn36xx: Fix missing frame timestamp for beacon/probe-resp Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 214/219] ath9k: fix OOB read ar9300_eeprom_restore_internal Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 215/219] ath9k: fix sleeping in atomic context Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 216/219] net: fix NULL pointer reference in cipso_v4_doi_free Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 217/219] fix array-index-out-of-bounds in taprio_change Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 218/219] net: w5100: check return value after calling platform_get_resource() Sasha Levin
2021-09-09 11:46 ` [PATCH AUTOSEL 5.13 219/219] net: hns3: clean up a type mismatch warning Sasha Levin
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