Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 335 insertions, 0 deletions

diff --git a/fs/hpfs/map.c b/fs/hpfs/map.c
new file mode 100644
index 000000000..be7323350
--- /dev/null
+++ b/fs/hpfs/map.c
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/map.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  mapping structures to memory with some minimal checks
+ */
+
+#include "hpfs_fn.h"
+
+__le32 *hpfs_map_dnode_bitmap(struct super_block *s, struct quad_buffer_head *qbh)
+{
+	return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0);
+}
+
+__le32 *hpfs_map_bitmap(struct super_block *s, unsigned bmp_block,
+			 struct quad_buffer_head *qbh, char *id)
+{
+	secno sec;
+	__le32 *ret;
+	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
+	if (hpfs_sb(s)->sb_chk) if (bmp_block >= n_bands) {
+		hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id);
+		return NULL;
+	}
+	sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
+	if (!sec || sec > hpfs_sb(s)->sb_fs_size-4) {
+		hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id);
+		return NULL;
+	}
+	ret = hpfs_map_4sectors(s, sec, qbh, 4);
+	if (ret) hpfs_prefetch_bitmap(s, bmp_block + 1);
+	return ret;
+}
+
+void hpfs_prefetch_bitmap(struct super_block *s, unsigned bmp_block)
+{
+	unsigned to_prefetch, next_prefetch;
+	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
+	if (unlikely(bmp_block >= n_bands))
+		return;
+	to_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
+	if (unlikely(bmp_block + 1 >= n_bands))
+		next_prefetch = 0;
+	else
+		next_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block + 1]);
+	hpfs_prefetch_sectors(s, to_prefetch, 4 + 4 * (to_prefetch + 4 == next_prefetch));
+}
+
+/*
+ * Load first code page into kernel memory, return pointer to 256-byte array,
+ * first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are
+ * lowercasing table
+ */
+
+unsigned char *hpfs_load_code_page(struct super_block *s, secno cps)
+{
+	struct buffer_head *bh;
+	secno cpds;
+	unsigned cpi;
+	unsigned char *ptr;
+	unsigned char *cp_table;
+	int i;
+	struct code_page_data *cpd;
+	struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0);
+	if (!cp) return NULL;
+	if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) {
+		pr_err("Code page directory magic doesn't match (magic = %08x)\n",
+			le32_to_cpu(cp->magic));
+		brelse(bh);
+		return NULL;
+	}
+	if (!le32_to_cpu(cp->n_code_pages)) {
+		pr_err("n_code_pages == 0\n");
+		brelse(bh);
+		return NULL;
+	}
+	cpds = le32_to_cpu(cp->array[0].code_page_data);
+	cpi = le16_to_cpu(cp->array[0].index);
+	brelse(bh);
+
+	if (cpi >= 3) {
+		pr_err("Code page index out of array\n");
+		return NULL;
+	}
+	
+	if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL;
+	if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
+		pr_err("Code page index out of sector\n");
+		brelse(bh);
+		return NULL;
+	}
+	ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
+	if (!(cp_table = kmalloc(256, GFP_KERNEL))) {
+		pr_err("out of memory for code page table\n");
+		brelse(bh);
+		return NULL;
+	}
+	memcpy(cp_table, ptr, 128);
+	brelse(bh);
+
+	/* Try to build lowercasing table from uppercasing one */
+
+	for (i=128; i<256; i++) cp_table[i]=i;
+	for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128)
+		cp_table[cp_table[i-128]] = i;
+	
+	return cp_table;
+}
+
+__le32 *hpfs_load_bitmap_directory(struct super_block *s, secno bmp)
+{
+	struct buffer_head *bh;
+	int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21;
+	int i;
+	__le32 *b;
+	if (!(b = kmalloc_array(n, 512, GFP_KERNEL))) {
+		pr_err("can't allocate memory for bitmap directory\n");
+		return NULL;
+	}	
+	for (i=0;i<n;i++) {
+		__le32 *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1);
+		if (!d) {
+			kfree(b);
+			return NULL;
+		}
+		memcpy((char *)b + 512 * i, d, 512);
+		brelse(bh);
+	}
+	return b;
+}
+
+void hpfs_load_hotfix_map(struct super_block *s, struct hpfs_spare_block *spareblock)
+{
+	struct quad_buffer_head qbh;
+	__le32 *directory;
+	u32 n_hotfixes, n_used_hotfixes;
+	unsigned i;
+
+	n_hotfixes = le32_to_cpu(spareblock->n_spares);
+	n_used_hotfixes = le32_to_cpu(spareblock->n_spares_used);
+
+	if (n_hotfixes > 256 || n_used_hotfixes > n_hotfixes) {
+		hpfs_error(s, "invalid number of hotfixes: %u, used: %u", n_hotfixes, n_used_hotfixes);
+		return;
+	}
+	if (!(directory = hpfs_map_4sectors(s, le32_to_cpu(spareblock->hotfix_map), &qbh, 0))) {
+		hpfs_error(s, "can't load hotfix map");
+		return;
+	}
+	for (i = 0; i < n_used_hotfixes; i++) {
+		hpfs_sb(s)->hotfix_from[i] = le32_to_cpu(directory[i]);
+		hpfs_sb(s)->hotfix_to[i] = le32_to_cpu(directory[n_hotfixes + i]);
+	}
+	hpfs_sb(s)->n_hotfixes = n_used_hotfixes;
+	hpfs_brelse4(&qbh);
+}
+
+/*
+ * Load fnode to memory
+ */
+
+struct fnode *hpfs_map_fnode(struct super_block *s, ino_t ino, struct buffer_head **bhp)
+{
+	struct fnode *fnode;
+	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) {
+		return NULL;
+	}
+	if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) {
+		if (hpfs_sb(s)->sb_chk) {
+			struct extended_attribute *ea;
+			struct extended_attribute *ea_end;
+			if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
+				hpfs_error(s, "bad magic on fnode %08lx",
+					(unsigned long)ino);
+				goto bail;
+			}
+			if (!fnode_is_dir(fnode)) {
+				if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes !=
+				    (bp_internal(GET_BTREE_PTR(&fnode->btree)) ? 12 : 8)) {
+					hpfs_error(s,
+					   "bad number of nodes in fnode %08lx",
+					    (unsigned long)ino);
+					goto bail;
+				}
+				if (le16_to_cpu(fnode->btree.first_free) !=
+				    8 + fnode->btree.n_used_nodes * (bp_internal(GET_BTREE_PTR(&fnode->btree)) ? 8 : 12)) {
+					hpfs_error(s,
+					    "bad first_free pointer in fnode %08lx",
+					    (unsigned long)ino);
+					goto bail;
+				}
+			}
+			if (le16_to_cpu(fnode->ea_size_s) && (le16_to_cpu(fnode->ea_offs) < 0xc4 ||
+			   le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200)) {
+				hpfs_error(s,
+					"bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
+					(unsigned long)ino,
+					le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
+				goto bail;
+			}
+			ea = fnode_ea(fnode);
+			ea_end = fnode_end_ea(fnode);
+			while (ea != ea_end) {
+				if (ea > ea_end) {
+					hpfs_error(s, "bad EA in fnode %08lx",
+						(unsigned long)ino);
+					goto bail;
+				}
+				ea = next_ea(ea);
+			}
+		}
+	}
+	return fnode;
+	bail:
+	brelse(*bhp);
+	return NULL;
+}
+
+struct anode *hpfs_map_anode(struct super_block *s, anode_secno ano, struct buffer_head **bhp)
+{
+	struct anode *anode;
+	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL;
+	if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD)))
+		if (hpfs_sb(s)->sb_chk) {
+			if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
+				hpfs_error(s, "bad magic on anode %08x", ano);
+				goto bail;
+			}
+			if (le32_to_cpu(anode->self) != ano) {
+				hpfs_error(s, "self pointer invalid on anode %08x", ano);
+				goto bail;
+			}
+			if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes !=
+			    (bp_internal(GET_BTREE_PTR(&anode->btree)) ? 60 : 40)) {
+				hpfs_error(s, "bad number of nodes in anode %08x", ano);
+				goto bail;
+			}
+			if (le16_to_cpu(anode->btree.first_free) !=
+			    8 + anode->btree.n_used_nodes * (bp_internal(GET_BTREE_PTR(&anode->btree)) ? 8 : 12)) {
+				hpfs_error(s, "bad first_free pointer in anode %08x", ano);
+				goto bail;
+			}
+		}
+	return anode;
+	bail:
+	brelse(*bhp);
+	return NULL;
+}
+
+/*
+ * Load dnode to memory and do some checks
+ */
+
+struct dnode *hpfs_map_dnode(struct super_block *s, unsigned secno,
+			     struct quad_buffer_head *qbh)
+{
+	struct dnode *dnode;
+	if (hpfs_sb(s)->sb_chk) {
+		if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL;
+		if (secno & 3) {
+			hpfs_error(s, "dnode %08x not byte-aligned", secno);
+			return NULL;
+		}	
+	}
+	if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD)))
+		if (hpfs_sb(s)->sb_chk) {
+			unsigned p, pp = 0;
+			unsigned char *d = (unsigned char *)dnode;
+			int b = 0;
+			if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
+				hpfs_error(s, "bad magic on dnode %08x", secno);
+				goto bail;
+			}
+			if (le32_to_cpu(dnode->self) != secno)
+				hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self));
+			/* Check dirents - bad dirents would cause infinite
+			   loops or shooting to memory */
+			if (le32_to_cpu(dnode->first_free) > 2048) {
+				hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free));
+				goto bail;
+			}
+			for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
+				struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p);
+				if (le16_to_cpu(de->length) > 292 || (le16_to_cpu(de->length) < 32) || (le16_to_cpu(de->length) & 3) || p + le16_to_cpu(de->length) > 2048) {
+					hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
+					goto bail;
+				}
+				if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) {
+					if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & SB_RDONLY) goto ok;
+					hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
+					goto bail;
+				}
+				ok:
+				if (hpfs_sb(s)->sb_chk >= 2) b |= 1 << de->down;
+				if (de->down) if (de_down_pointer(de) < 0x10) {
+					hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp);
+					goto bail;
+				}
+				pp = p;
+				
+			}
+			if (p != le32_to_cpu(dnode->first_free)) {
+				hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno);
+				goto bail;
+			}
+			if (d[pp + 30] != 1 || d[pp + 31] != 255) {
+				hpfs_error(s, "dnode %08x does not end with \\377 entry", secno);
+				goto bail;
+			}
+			if (b == 3)
+				pr_err("unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n",
+					secno);
+		}
+	return dnode;
+	bail:
+	hpfs_brelse4(qbh);
+	return NULL;
+}
+
+dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino)
+{
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	dnode_secno dno;
+
+	fnode = hpfs_map_fnode(s, ino, &bh);
+	if (!fnode)
+		return 0;
+
+	dno = le32_to_cpu(fnode->u.external[0].disk_secno);
+	brelse(bh);
+	return dno;
+}