selftests/bpf: Add a test for objects stuck in free_by_rcu_ttracegrafted

Delete all elements of BPF_F_NO_PREALLOC hash map in one batch. The first
free_bulk() starts RCU tasks trace GP and the rest of the elements are
freed while it's in flight. Wait for call_rcu_ttrace_in_progress to clear
in bpf_mem_cache of every cpu and check that free_by_rcu_ttrace and
waiting_for_gp_ttrace lists are empty.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20260930095920.601738-4-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 289 insertions, 0 deletions

diff --git a/fs/udf/misc.c b/fs/udf/misc.c
new file mode 100644
index 000000000..6928e378f
--- /dev/null
+++ b/fs/udf/misc.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * misc.c
+ *
+ * PURPOSE
+ *	Miscellaneous routines for the OSTA-UDF(tm) filesystem.
+ *
+ * COPYRIGHT
+ *  (C) 1998 Dave Boynton
+ *  (C) 1998-2004 Ben Fennema
+ *  (C) 1999-2000 Stelias Computing Inc
+ *
+ * HISTORY
+ *
+ *  04/19/99 blf  partial support for reading/writing specific EA's
+ */
+
+#include "udfdecl.h"
+
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/crc-itu-t.h>
+
+#include "udf_i.h"
+#include "udf_sb.h"
+
+struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size,
+					   uint32_t type, uint8_t loc)
+{
+	uint8_t *ea = NULL, *ad = NULL;
+	int offset;
+	uint16_t crclen;
+	struct udf_inode_info *iinfo = UDF_I(inode);
+
+	ea = iinfo->i_data;
+	if (iinfo->i_lenEAttr) {
+		ad = iinfo->i_data + iinfo->i_lenEAttr;
+	} else {
+		ad = ea;
+		size += sizeof(struct extendedAttrHeaderDesc);
+	}
+
+	offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
+		iinfo->i_lenAlloc;
+
+	/* TODO - Check for FreeEASpace */
+
+	if (loc & 0x01 && offset >= size) {
+		struct extendedAttrHeaderDesc *eahd;
+		eahd = (struct extendedAttrHeaderDesc *)ea;
+
+		if (iinfo->i_lenAlloc)
+			memmove(&ad[size], ad, iinfo->i_lenAlloc);
+
+		if (iinfo->i_lenEAttr) {
+			/* check checksum/crc */
+			if (eahd->descTag.tagIdent !=
+					cpu_to_le16(TAG_IDENT_EAHD) ||
+			    le32_to_cpu(eahd->descTag.tagLocation) !=
+					iinfo->i_location.logicalBlockNum)
+				return NULL;
+		} else {
+			struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
+
+			size -= sizeof(struct extendedAttrHeaderDesc);
+			iinfo->i_lenEAttr +=
+				sizeof(struct extendedAttrHeaderDesc);
+			eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
+			if (sbi->s_udfrev >= 0x0200)
+				eahd->descTag.descVersion = cpu_to_le16(3);
+			else
+				eahd->descTag.descVersion = cpu_to_le16(2);
+			eahd->descTag.tagSerialNum =
+					cpu_to_le16(sbi->s_serial_number);
+			eahd->descTag.tagLocation = cpu_to_le32(
+					iinfo->i_location.logicalBlockNum);
+			eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
+			eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
+		}
+
+		offset = iinfo->i_lenEAttr;
+		if (type < 2048) {
+			if (le32_to_cpu(eahd->appAttrLocation) <
+					iinfo->i_lenEAttr) {
+				uint32_t aal =
+					le32_to_cpu(eahd->appAttrLocation);
+				memmove(&ea[offset - aal + size],
+					&ea[aal], offset - aal);
+				offset -= aal;
+				eahd->appAttrLocation =
+						cpu_to_le32(aal + size);
+			}
+			if (le32_to_cpu(eahd->impAttrLocation) <
+					iinfo->i_lenEAttr) {
+				uint32_t ial =
+					le32_to_cpu(eahd->impAttrLocation);
+				memmove(&ea[offset - ial + size],
+					&ea[ial], offset - ial);
+				offset -= ial;
+				eahd->impAttrLocation =
+						cpu_to_le32(ial + size);
+			}
+		} else if (type < 65536) {
+			if (le32_to_cpu(eahd->appAttrLocation) <
+					iinfo->i_lenEAttr) {
+				uint32_t aal =
+					le32_to_cpu(eahd->appAttrLocation);
+				memmove(&ea[offset - aal + size],
+					&ea[aal], offset - aal);
+				offset -= aal;
+				eahd->appAttrLocation =
+						cpu_to_le32(aal + size);
+			}
+		}
+		/* rewrite CRC + checksum of eahd */
+		crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(struct tag);
+		eahd->descTag.descCRCLength = cpu_to_le16(crclen);
+		eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd +
+						sizeof(struct tag), crclen));
+		eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag);
+		iinfo->i_lenEAttr += size;
+		return (struct genericFormat *)&ea[offset];
+	}
+
+	return NULL;
+}
+
+struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
+					   uint8_t subtype)
+{
+	struct genericFormat *gaf;
+	uint8_t *ea = NULL;
+	uint32_t offset;
+	struct udf_inode_info *iinfo = UDF_I(inode);
+
+	ea = iinfo->i_data;
+
+	if (iinfo->i_lenEAttr) {
+		struct extendedAttrHeaderDesc *eahd;
+		eahd = (struct extendedAttrHeaderDesc *)ea;
+
+		/* check checksum/crc */
+		if (eahd->descTag.tagIdent !=
+				cpu_to_le16(TAG_IDENT_EAHD) ||
+		    le32_to_cpu(eahd->descTag.tagLocation) !=
+				iinfo->i_location.logicalBlockNum)
+			return NULL;
+
+		if (type < 2048)
+			offset = sizeof(struct extendedAttrHeaderDesc);
+		else if (type < 65536)
+			offset = le32_to_cpu(eahd->impAttrLocation);
+		else
+			offset = le32_to_cpu(eahd->appAttrLocation);
+
+		while (offset + sizeof(*gaf) < iinfo->i_lenEAttr) {
+			uint32_t attrLength;
+
+			gaf = (struct genericFormat *)&ea[offset];
+			attrLength = le32_to_cpu(gaf->attrLength);
+
+			/* Detect undersized elements and buffer overflows */
+			if ((attrLength < sizeof(*gaf)) ||
+			    (attrLength > (iinfo->i_lenEAttr - offset)))
+				break;
+
+			if (le32_to_cpu(gaf->attrType) == type &&
+					gaf->attrSubtype == subtype)
+				return gaf;
+			else
+				offset += attrLength;
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * udf_read_tagged
+ *
+ * PURPOSE
+ *	Read the first block of a tagged descriptor.
+ *
+ * HISTORY
+ *	July 1, 1997 - Andrew E. Mileski
+ *	Written, tested, and released.
+ */
+struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block,
+				    uint32_t location, uint16_t *ident)
+{
+	struct tag *tag_p;
+	struct buffer_head *bh = NULL;
+	u8 checksum;
+
+	/* Read the block */
+	if (block == 0xFFFFFFFF)
+		return NULL;
+
+	bh = sb_bread(sb, block);
+	if (!bh) {
+		udf_err(sb, "read failed, block=%u, location=%u\n",
+			block, location);
+		return NULL;
+	}
+
+	tag_p = (struct tag *)(bh->b_data);
+
+	*ident = le16_to_cpu(tag_p->tagIdent);
+
+	if (location != le32_to_cpu(tag_p->tagLocation)) {
+		udf_debug("location mismatch block %u, tag %u != %u\n",
+			  block, le32_to_cpu(tag_p->tagLocation), location);
+		goto error_out;
+	}
+
+	/* Verify the tag checksum */
+	checksum = udf_tag_checksum(tag_p);
+	if (checksum != tag_p->tagChecksum) {
+		udf_err(sb, "tag checksum failed, block %u: 0x%02x != 0x%02x\n",
+			block, checksum, tag_p->tagChecksum);
+		goto error_out;
+	}
+
+	/* Verify the tag version */
+	if (tag_p->descVersion != cpu_to_le16(0x0002U) &&
+	    tag_p->descVersion != cpu_to_le16(0x0003U)) {
+		udf_err(sb, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n",
+			le16_to_cpu(tag_p->descVersion), block);
+		goto error_out;
+	}
+
+	/* Verify the descriptor CRC */
+	if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize) {
+		udf_err(sb, "block %u: CRC length %u exceeds block size\n",
+			block, le16_to_cpu(tag_p->descCRCLength));
+		goto error_out;
+	}
+	if (le16_to_cpu(tag_p->descCRC) == crc_itu_t(0,
+					bh->b_data + sizeof(struct tag),
+					le16_to_cpu(tag_p->descCRCLength)))
+		return bh;
+
+	udf_debug("Crc failure block %u: crc = %u, crclen = %u\n", block,
+		  le16_to_cpu(tag_p->descCRC),
+		  le16_to_cpu(tag_p->descCRCLength));
+error_out:
+	brelse(bh);
+	return NULL;
+}
+
+struct buffer_head *udf_read_ptagged(struct super_block *sb,
+				     struct kernel_lb_addr *loc,
+				     uint32_t offset, uint16_t *ident)
+{
+	return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
+			       loc->logicalBlockNum + offset, ident);
+}
+
+void udf_update_tag(char *data, int length)
+{
+	struct tag *tptr = (struct tag *)data;
+	length -= sizeof(struct tag);
+
+	tptr->descCRCLength = cpu_to_le16(length);
+	tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length));
+	tptr->tagChecksum = udf_tag_checksum(tptr);
+}
+
+void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
+		 uint32_t loc, int length)
+{
+	struct tag *tptr = (struct tag *)data;
+	tptr->tagIdent = cpu_to_le16(ident);
+	tptr->descVersion = cpu_to_le16(version);
+	tptr->tagSerialNum = cpu_to_le16(snum);
+	tptr->tagLocation = cpu_to_le32(loc);
+	udf_update_tag(data, length);
+}
+
+u8 udf_tag_checksum(const struct tag *t)
+{
+	u8 *data = (u8 *)t;
+	u8 checksum = 0;
+	int i;
+	for (i = 0; i < sizeof(struct tag); ++i)
+		if (i != 4) /* position of checksum */
+			checksum += data[i];
+	return checksum;
+}