From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- fs/ceph/mdsmap.c | 471 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 471 insertions(+) create mode 100644 fs/ceph/mdsmap.c (limited to 'fs/ceph/mdsmap.c') diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c new file mode 100644 index 000000000..53079ef34 --- /dev/null +++ b/fs/ceph/mdsmap.c @@ -0,0 +1,471 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "mdsmap.h" +#include "mds_client.h" +#include "super.h" + +#define CEPH_MDS_IS_READY(i, ignore_laggy) \ + (m->m_info[i].state > 0 && (ignore_laggy ? true : !m->m_info[i].laggy)) + +static int __mdsmap_get_random_mds(struct ceph_mdsmap *m, bool ignore_laggy) +{ + int n = 0; + int i, j; + + /* count */ + for (i = 0; i < m->possible_max_rank; i++) + if (CEPH_MDS_IS_READY(i, ignore_laggy)) + n++; + if (n == 0) + return -1; + + /* pick */ + n = get_random_u32_below(n); + for (j = 0, i = 0; i < m->possible_max_rank; i++) { + if (CEPH_MDS_IS_READY(i, ignore_laggy)) + j++; + if (j > n) + break; + } + + return i; +} + +/* + * choose a random mds that is "up" (i.e. has a state > 0), or -1. + */ +int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) +{ + int mds; + + mds = __mdsmap_get_random_mds(m, false); + if (mds == m->possible_max_rank || mds == -1) + mds = __mdsmap_get_random_mds(m, true); + + return mds == m->possible_max_rank ? -1 : mds; +} + +#define __decode_and_drop_type(p, end, type, bad) \ + do { \ + if (*p + sizeof(type) > end) \ + goto bad; \ + *p += sizeof(type); \ + } while (0) + +#define __decode_and_drop_set(p, end, type, bad) \ + do { \ + u32 n; \ + size_t need; \ + ceph_decode_32_safe(p, end, n, bad); \ + need = sizeof(type) * n; \ + ceph_decode_need(p, end, need, bad); \ + *p += need; \ + } while (0) + +#define __decode_and_drop_map(p, end, ktype, vtype, bad) \ + do { \ + u32 n; \ + size_t need; \ + ceph_decode_32_safe(p, end, n, bad); \ + need = (sizeof(ktype) + sizeof(vtype)) * n; \ + ceph_decode_need(p, end, need, bad); \ + *p += need; \ + } while (0) + + +static int __decode_and_drop_compat_set(void **p, void* end) +{ + int i; + /* compat, ro_compat, incompat*/ + for (i = 0; i < 3; i++) { + u32 n; + ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad); + /* mask */ + *p += sizeof(u64); + /* names (map) */ + n = ceph_decode_32(p); + while (n-- > 0) { + u32 len; + ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), + bad); + *p += sizeof(u64); + len = ceph_decode_32(p); + ceph_decode_need(p, end, len, bad); + *p += len; + } + } + return 0; +bad: + return -1; +} + +/* + * Decode an MDS map + * + * Ignore any fields we don't care about (there are quite a few of + * them). + */ +struct ceph_mdsmap *ceph_mdsmap_decode(struct ceph_mds_client *mdsc, void **p, + void *end, bool msgr2) +{ + struct ceph_client *cl = mdsc->fsc->client; + struct ceph_mdsmap *m; + const void *start = *p; + int i, j, n; + int err; + u8 mdsmap_v; + u16 mdsmap_ev; + u32 target; + size_t export_targets_len; + + m = kzalloc_obj(*m, GFP_NOFS); + if (!m) + return ERR_PTR(-ENOMEM); + + ceph_decode_need(p, end, 1 + 1, bad); + mdsmap_v = ceph_decode_8(p); + *p += sizeof(u8); /* mdsmap_cv */ + if (mdsmap_v >= 4) { + u32 mdsmap_len; + ceph_decode_32_safe(p, end, mdsmap_len, bad); + if (end < *p + mdsmap_len) + goto bad; + end = *p + mdsmap_len; + } + + ceph_decode_need(p, end, 8*sizeof(u32) + sizeof(u64), bad); + m->m_epoch = ceph_decode_32(p); + m->m_client_epoch = ceph_decode_32(p); + m->m_last_failure = ceph_decode_32(p); + m->m_root = ceph_decode_32(p); + m->m_session_timeout = ceph_decode_32(p); + m->m_session_autoclose = ceph_decode_32(p); + m->m_max_file_size = ceph_decode_64(p); + m->m_max_mds = ceph_decode_32(p); + + /* + * pick out the active nodes as the m_num_active_mds, the + * m_num_active_mds maybe larger than m_max_mds when decreasing + * the max_mds in cluster side, in other case it should less + * than or equal to m_max_mds. + */ + m->m_num_active_mds = n = ceph_decode_32(p); + + /* + * the possible max rank, it maybe larger than the m_num_active_mds, + * for example if the mds_max == 2 in the cluster, when the MDS(0) + * was laggy and being replaced by a new MDS, we will temporarily + * receive a new mds map with n_num_mds == 1 and the active MDS(1), + * and the mds rank >= m_num_active_mds. + */ + m->possible_max_rank = max(m->m_num_active_mds, m->m_max_mds); + + m->m_info = kzalloc_objs(*m->m_info, m->possible_max_rank, GFP_NOFS); + if (!m->m_info) + goto nomem; + + /* pick out active nodes from mds_info (state > 0) */ + for (i = 0; i < n; i++) { + u64 global_id; + u32 namelen; + s32 mds, inc, state; + u8 info_v; + void *info_end = NULL; + struct ceph_entity_addr addr; + u32 num_export_targets; + void *pexport_targets = NULL; + struct ceph_timespec laggy_since; + struct ceph_mds_info *info; + bool laggy; + + ceph_decode_need(p, end, sizeof(u64) + 1, bad); + global_id = ceph_decode_64(p); + info_v= ceph_decode_8(p); + if (info_v >= 4) { + u32 info_len; + ceph_decode_need(p, end, 1 + sizeof(u32), bad); + *p += sizeof(u8); /* info_cv */ + info_len = ceph_decode_32(p); + info_end = *p + info_len; + if (info_end > end) + goto bad; + } + + ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad); + *p += sizeof(u64); + namelen = ceph_decode_32(p); /* skip mds name */ + *p += namelen; + + ceph_decode_32_safe(p, end, mds, bad); + ceph_decode_32_safe(p, end, inc, bad); + ceph_decode_32_safe(p, end, state, bad); + *p += sizeof(u64); /* state_seq */ + if (info_v >= 8) + err = ceph_decode_entity_addrvec(p, end, msgr2, &addr); + else + err = ceph_decode_entity_addr(p, end, &addr); + if (err) + goto corrupt; + + ceph_decode_copy_safe(p, end, &laggy_since, sizeof(laggy_since), + bad); + laggy = laggy_since.tv_sec != 0 || laggy_since.tv_nsec != 0; + *p += sizeof(u32); + ceph_decode_32_safe(p, end, namelen, bad); + *p += namelen; + if (info_v >= 2) { + ceph_decode_32_safe(p, end, num_export_targets, bad); + export_targets_len = size_mul(num_export_targets, + sizeof(u32)); + ceph_decode_need(p, end, export_targets_len, bad); + pexport_targets = *p; + *p += export_targets_len; + } else { + num_export_targets = 0; + } + + if (info_end && *p != info_end) { + if (*p > info_end) + goto bad; + *p = info_end; + } + + doutc(cl, "%d/%d %lld mds%d.%d %s %s%s\n", i+1, n, global_id, + mds, inc, ceph_pr_addr(&addr), + ceph_mds_state_name(state), laggy ? "(laggy)" : ""); + + if (mds < 0 || mds >= m->possible_max_rank) { + pr_warn_client(cl, "got incorrect mds(%d)\n", mds); + continue; + } + + if (state <= 0) { + doutc(cl, "got incorrect state(%s)\n", + ceph_mds_state_name(state)); + continue; + } + + info = &m->m_info[mds]; + info->global_id = global_id; + info->state = state; + info->addr = addr; + info->laggy = laggy; + info->num_export_targets = num_export_targets; + if (num_export_targets) { + info->export_targets = kcalloc(num_export_targets, + sizeof(u32), GFP_NOFS); + if (!info->export_targets) + goto nomem; + for (j = 0; j < num_export_targets; j++) { + target = ceph_decode_32(&pexport_targets); + if (target >= CEPH_MAX_MDS) { + err = -EIO; + goto corrupt; + } + info->export_targets[j] = target; + } + } else { + info->export_targets = NULL; + } + } + + /* pg_pools */ + ceph_decode_32_safe(p, end, n, bad); + m->m_num_data_pg_pools = n; + m->m_data_pg_pools = kcalloc(n, sizeof(u64), GFP_NOFS); + if (!m->m_data_pg_pools) + goto nomem; + ceph_decode_need(p, end, sizeof(u64)*(n+1), bad); + for (i = 0; i < n; i++) + m->m_data_pg_pools[i] = ceph_decode_64(p); + m->m_cas_pg_pool = ceph_decode_64(p); + m->m_enabled = m->m_epoch > 1; + + mdsmap_ev = 1; + if (mdsmap_v >= 2) { + ceph_decode_16_safe(p, end, mdsmap_ev, bad_ext); + } + if (mdsmap_ev >= 3) { + if (__decode_and_drop_compat_set(p, end) < 0) + goto bad_ext; + } + /* metadata_pool */ + if (mdsmap_ev < 5) { + __decode_and_drop_type(p, end, u32, bad_ext); + } else { + __decode_and_drop_type(p, end, u64, bad_ext); + } + + /* created + modified + tableserver */ + __decode_and_drop_type(p, end, struct ceph_timespec, bad_ext); + __decode_and_drop_type(p, end, struct ceph_timespec, bad_ext); + __decode_and_drop_type(p, end, u32, bad_ext); + + /* in */ + { + int num_laggy = 0; + ceph_decode_32_safe(p, end, n, bad_ext); + ceph_decode_need(p, end, sizeof(u32) * n, bad_ext); + + for (i = 0; i < n; i++) { + s32 mds = ceph_decode_32(p); + if (mds >= 0 && mds < m->possible_max_rank) { + if (m->m_info[mds].laggy) + num_laggy++; + } + } + m->m_num_laggy = num_laggy; + + if (n > m->possible_max_rank) { + void *new_m_info = krealloc(m->m_info, + n * sizeof(*m->m_info), + GFP_NOFS | __GFP_ZERO); + if (!new_m_info) + goto nomem; + m->m_info = new_m_info; + } + m->possible_max_rank = n; + } + + /* inc */ + __decode_and_drop_map(p, end, u32, u32, bad_ext); + /* up */ + __decode_and_drop_map(p, end, u32, u64, bad_ext); + /* failed */ + __decode_and_drop_set(p, end, u32, bad_ext); + /* stopped */ + __decode_and_drop_set(p, end, u32, bad_ext); + + if (mdsmap_ev >= 4) { + /* last_failure_osd_epoch */ + __decode_and_drop_type(p, end, u32, bad_ext); + } + if (mdsmap_ev >= 6) { + /* ever_allowed_snaps */ + __decode_and_drop_type(p, end, u8, bad_ext); + /* explicitly_allowed_snaps */ + __decode_and_drop_type(p, end, u8, bad_ext); + } + if (mdsmap_ev >= 7) { + /* inline_data_enabled */ + __decode_and_drop_type(p, end, u8, bad_ext); + } + if (mdsmap_ev >= 8) { + size_t fsname_len; + + /* enabled */ + ceph_decode_8_safe(p, end, m->m_enabled, bad_ext); + + /* fs_name */ + m->m_fs_name = ceph_extract_encoded_string(p, end, + &fsname_len, + GFP_NOFS); + if (IS_ERR(m->m_fs_name)) { + m->m_fs_name = NULL; + goto nomem; + } + + /* validate fsname against mds_namespace */ + if (!namespace_equals(mdsc->fsc->mount_options, m->m_fs_name, + fsname_len)) { + pr_warn_client(cl, "fsname %s doesn't match mds_namespace %s\n", + m->m_fs_name, + mdsc->fsc->mount_options->mds_namespace); + goto bad; + } + } else { + m->m_enabled = false; + m->m_fs_name = kstrdup(CEPH_OLD_FS_NAME, GFP_NOFS); + if (!m->m_fs_name) + goto nomem; + } + /* damaged */ + if (mdsmap_ev >= 9) { + size_t need; + ceph_decode_32_safe(p, end, n, bad_ext); + need = sizeof(u32) * n; + ceph_decode_need(p, end, need, bad_ext); + *p += need; + m->m_damaged = n > 0; + } else { + m->m_damaged = false; + } + if (mdsmap_ev >= 17) { + /* balancer */ + ceph_decode_skip_string(p, end, bad_ext); + /* standby_count_wanted */ + ceph_decode_skip_32(p, end, bad_ext); + /* old_max_mds */ + ceph_decode_skip_32(p, end, bad_ext); + /* min_compat_client */ + ceph_decode_skip_8(p, end, bad_ext); + /* required_client_features */ + ceph_decode_skip_set(p, end, 64, bad_ext); + /* bal_rank_mask */ + ceph_decode_skip_string(p, end, bad_ext); + } + if (mdsmap_ev >= 18) { + ceph_decode_64_safe(p, end, m->m_max_xattr_size, bad_ext); + } +bad_ext: + doutc(cl, "m_enabled: %d, m_damaged: %d, m_num_laggy: %d\n", + !!m->m_enabled, !!m->m_damaged, m->m_num_laggy); + *p = end; + doutc(cl, "success epoch %u\n", m->m_epoch); + return m; +nomem: + err = -ENOMEM; + goto out_err; +corrupt: + pr_err_client(cl, "corrupt mdsmap\n"); + print_hex_dump(KERN_DEBUG, "mdsmap: ", + DUMP_PREFIX_OFFSET, 16, 1, + start, end - start, true); +out_err: + ceph_mdsmap_destroy(m); + return ERR_PTR(err); +bad: + err = -EINVAL; + goto corrupt; +} + +void ceph_mdsmap_destroy(struct ceph_mdsmap *m) +{ + int i; + + if (m->m_info) { + for (i = 0; i < m->possible_max_rank; i++) + kfree(m->m_info[i].export_targets); + kfree(m->m_info); + } + kfree(m->m_data_pg_pools); + kfree(m->m_fs_name); + kfree(m); +} + +bool ceph_mdsmap_is_cluster_available(struct ceph_mdsmap *m) +{ + int i, nr_active = 0; + if (!m->m_enabled) + return false; + if (m->m_damaged) + return false; + if (m->m_num_laggy == m->m_num_active_mds) + return false; + for (i = 0; i < m->possible_max_rank; i++) { + if (m->m_info[i].state == CEPH_MDS_STATE_ACTIVE) + nr_active++; + } + return nr_active > 0; +} -- cgit v1.3.1