ftrace: Synchronize the initialization of ftrace_opsgrafted

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 <rostedt@goodmis.org>

1 files changed, 340 insertions, 0 deletions

diff --git a/fs/udf/partition.c b/fs/udf/partition.c
new file mode 100644
index 000000000..ad8dcedca
--- /dev/null
+++ b/fs/udf/partition.c
@@ -0,0 +1,340 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * partition.c
+ *
+ * PURPOSE
+ *      Partition handling routines for the OSTA-UDF(tm) filesystem.
+ *
+ * COPYRIGHT
+ *  (C) 1998-2001 Ben Fennema
+ *
+ * HISTORY
+ *
+ * 12/06/98 blf  Created file.
+ *
+ */
+
+#include "udfdecl.h"
+#include "udf_sb.h"
+#include "udf_i.h"
+
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/mutex.h>
+
+uint32_t udf_get_pblock(struct super_block *sb, uint32_t block,
+			uint16_t partition, uint32_t offset)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	struct udf_part_map *map;
+	if (partition >= sbi->s_partitions) {
+		udf_debug("block=%u, partition=%u, offset=%u: invalid partition\n",
+			  block, partition, offset);
+		return 0xFFFFFFFF;
+	}
+	map = &sbi->s_partmaps[partition];
+	if (map->s_partition_func)
+		return map->s_partition_func(sb, block, partition, offset);
+	else
+		return map->s_partition_root + block + offset;
+}
+
+uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block,
+			       uint16_t partition, uint32_t offset)
+{
+	struct buffer_head *bh = NULL;
+	uint32_t newblock;
+	uint32_t index;
+	uint32_t loc;
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	struct udf_part_map *map;
+	struct udf_virtual_data *vdata;
+	struct udf_inode_info *iinfo = UDF_I(sbi->s_vat_inode);
+	int err;
+
+	map = &sbi->s_partmaps[partition];
+	vdata = &map->s_type_specific.s_virtual;
+
+	if (block >= vdata->s_num_entries) {
+		udf_debug("Trying to access block beyond end of VAT (%u max %u)\n",
+			  block, vdata->s_num_entries);
+		return 0xFFFFFFFF;
+	}
+
+	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+		loc = le32_to_cpu(((__le32 *)(iinfo->i_data +
+			vdata->s_start_offset))[block]);
+		goto translate;
+	}
+	index = (sb->s_blocksize - vdata->s_start_offset) / sizeof(uint32_t);
+	if (block >= index) {
+		block -= index;
+		newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
+		index = block % (sb->s_blocksize / sizeof(uint32_t));
+	} else {
+		newblock = 0;
+		index = vdata->s_start_offset / sizeof(uint32_t) + block;
+	}
+
+	bh = udf_bread(sbi->s_vat_inode, newblock, 0, &err);
+	if (!bh) {
+		udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%u,%u)\n",
+			  sb, block, partition);
+		return 0xFFFFFFFF;
+	}
+
+	loc = le32_to_cpu(((__le32 *)bh->b_data)[index]);
+
+	brelse(bh);
+
+translate:
+	if (iinfo->i_location.partitionReferenceNum == partition) {
+		udf_debug("recursive call to udf_get_pblock!\n");
+		return 0xFFFFFFFF;
+	}
+
+	return udf_get_pblock(sb, loc,
+			      iinfo->i_location.partitionReferenceNum,
+			      offset);
+}
+
+inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block,
+				      uint16_t partition, uint32_t offset)
+{
+	return udf_get_pblock_virt15(sb, block, partition, offset);
+}
+
+uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block,
+			       uint16_t partition, uint32_t offset)
+{
+	int i;
+	struct sparingTable *st = NULL;
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	struct udf_part_map *map;
+	uint32_t packet;
+	struct udf_sparing_data *sdata;
+
+	map = &sbi->s_partmaps[partition];
+	sdata = &map->s_type_specific.s_sparing;
+	packet = (block + offset) & ~(sdata->s_packet_len - 1);
+
+	for (i = 0; i < 4; i++) {
+		if (sdata->s_spar_map[i] != NULL) {
+			st = (struct sparingTable *)
+					sdata->s_spar_map[i]->b_data;
+			break;
+		}
+	}
+
+	if (st) {
+		for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {
+			struct sparingEntry *entry = &st->mapEntry[i];
+			u32 origLoc = le32_to_cpu(entry->origLocation);
+			if (origLoc >= 0xFFFFFFF0)
+				break;
+			else if (origLoc == packet)
+				return le32_to_cpu(entry->mappedLocation) +
+					((block + offset) &
+						(sdata->s_packet_len - 1));
+			else if (origLoc > packet)
+				break;
+		}
+	}
+
+	return map->s_partition_root + block + offset;
+}
+
+int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
+{
+	struct udf_sparing_data *sdata;
+	struct sparingTable *st = NULL;
+	struct sparingEntry mapEntry;
+	uint32_t packet;
+	int i, j, k, l;
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	u16 reallocationTableLen;
+	struct buffer_head *bh;
+	int ret = 0;
+
+	mutex_lock(&sbi->s_alloc_mutex);
+	for (i = 0; i < sbi->s_partitions; i++) {
+		struct udf_part_map *map = &sbi->s_partmaps[i];
+		if (old_block > map->s_partition_root &&
+		    old_block < map->s_partition_root + map->s_partition_len) {
+			sdata = &map->s_type_specific.s_sparing;
+			packet = (old_block - map->s_partition_root) &
+						~(sdata->s_packet_len - 1);
+
+			for (j = 0; j < 4; j++)
+				if (sdata->s_spar_map[j] != NULL) {
+					st = (struct sparingTable *)
+						sdata->s_spar_map[j]->b_data;
+					break;
+				}
+
+			if (!st) {
+				ret = 1;
+				goto out;
+			}
+
+			reallocationTableLen =
+					le16_to_cpu(st->reallocationTableLen);
+			for (k = 0; k < reallocationTableLen; k++) {
+				struct sparingEntry *entry = &st->mapEntry[k];
+				u32 origLoc = le32_to_cpu(entry->origLocation);
+
+				if (origLoc == 0xFFFFFFFF) {
+					for (; j < 4; j++) {
+						int len;
+						bh = sdata->s_spar_map[j];
+						if (!bh)
+							continue;
+
+						st = (struct sparingTable *)
+								bh->b_data;
+						entry->origLocation =
+							cpu_to_le32(packet);
+						len =
+						  sizeof(struct sparingTable) +
+						  reallocationTableLen *
+						  sizeof(struct sparingEntry);
+						udf_update_tag((char *)st, len);
+						mark_buffer_dirty(bh);
+					}
+					*new_block = le32_to_cpu(
+							entry->mappedLocation) +
+						     ((old_block -
+							map->s_partition_root) &
+						     (sdata->s_packet_len - 1));
+					ret = 0;
+					goto out;
+				} else if (origLoc == packet) {
+					*new_block = le32_to_cpu(
+							entry->mappedLocation) +
+						     ((old_block -
+							map->s_partition_root) &
+						     (sdata->s_packet_len - 1));
+					ret = 0;
+					goto out;
+				} else if (origLoc > packet)
+					break;
+			}
+
+			for (l = k; l < reallocationTableLen; l++) {
+				struct sparingEntry *entry = &st->mapEntry[l];
+				u32 origLoc = le32_to_cpu(entry->origLocation);
+
+				if (origLoc != 0xFFFFFFFF)
+					continue;
+
+				for (; j < 4; j++) {
+					bh = sdata->s_spar_map[j];
+					if (!bh)
+						continue;
+
+					st = (struct sparingTable *)bh->b_data;
+					mapEntry = st->mapEntry[l];
+					mapEntry.origLocation =
+							cpu_to_le32(packet);
+					memmove(&st->mapEntry[k + 1],
+						&st->mapEntry[k],
+						(l - k) *
+						sizeof(struct sparingEntry));
+					st->mapEntry[k] = mapEntry;
+					udf_update_tag((char *)st,
+						sizeof(struct sparingTable) +
+						reallocationTableLen *
+						sizeof(struct sparingEntry));
+					mark_buffer_dirty(bh);
+				}
+				*new_block =
+					le32_to_cpu(
+					      st->mapEntry[k].mappedLocation) +
+					((old_block - map->s_partition_root) &
+					 (sdata->s_packet_len - 1));
+				ret = 0;
+				goto out;
+			}
+
+			ret = 1;
+			goto out;
+		} /* if old_block */
+	}
+
+	if (i == sbi->s_partitions) {
+		/* outside of partitions */
+		/* for now, fail =) */
+		ret = 1;
+	}
+
+out:
+	mutex_unlock(&sbi->s_alloc_mutex);
+	return ret;
+}
+
+static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
+					uint16_t partition, uint32_t offset)
+{
+	struct super_block *sb = inode->i_sb;
+	struct udf_part_map *map;
+	struct kernel_lb_addr eloc;
+	uint32_t elen;
+	sector_t ext_offset;
+	struct extent_position epos = {};
+	uint32_t phyblock;
+	int8_t etype;
+	int err = 0;
+
+	err = inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset, &etype);
+	if (err <= 0 || etype != (EXT_RECORDED_ALLOCATED >> 30))
+		phyblock = 0xFFFFFFFF;
+	else {
+		map = &UDF_SB(sb)->s_partmaps[partition];
+		/* map to sparable/physical partition desc */
+		phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
+			map->s_type_specific.s_metadata.s_phys_partition_ref,
+			ext_offset + offset);
+	}
+
+	brelse(epos.bh);
+	return phyblock;
+}
+
+uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
+				uint16_t partition, uint32_t offset)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	struct udf_part_map *map;
+	struct udf_meta_data *mdata;
+	uint32_t retblk;
+	struct inode *inode;
+
+	udf_debug("READING from METADATA\n");
+
+	map = &sbi->s_partmaps[partition];
+	mdata = &map->s_type_specific.s_metadata;
+	inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe;
+
+	if (!inode)
+		return 0xFFFFFFFF;
+
+	retblk = udf_try_read_meta(inode, block, partition, offset);
+	if (retblk == 0xFFFFFFFF && mdata->s_metadata_fe) {
+		udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n");
+		if (!(mdata->s_flags & MF_MIRROR_FE_LOADED)) {
+			mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb,
+				mdata->s_mirror_file_loc,
+				mdata->s_phys_partition_ref);
+			if (IS_ERR(mdata->s_mirror_fe))
+				mdata->s_mirror_fe = NULL;
+			mdata->s_flags |= MF_MIRROR_FE_LOADED;
+		}
+
+		inode = mdata->s_mirror_fe;
+		if (!inode)
+			return 0xFFFFFFFF;
+		retblk = udf_try_read_meta(inode, block, partition, offset);
+	}
+
+	return retblk;
+}