bfs: add sanity check at bfs_fill_super()

From: Tetsuo Handa <[email protected]>

[ Upstream commit 9f2df09a33aa2c76ce6385d382693f98d7f2f07e ]

syzbot is reporting too large memory allocation at bfs_fill_super() [1]. Since file system image is corrupted such that bfs_sb->s_start == 0, bfs_fill_super() is trying to allocate 8MB of continuous memory. Fix this by adding a sanity check on bfs_sb->s_start, __GFP_NOWARN and printf().

[1] https://syzkaller.appspot.com/bug?id=16a87c236b951351374a84c8a32f40edbc034e96

---
 fs/bfs/inode.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

index fdcb4d69f430..4714c55c1ae5 100644
@@ -350,7 +350,8 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
 
 	s->s_magic = BFS_MAGIC;
 
-	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
+	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) ||
+	    le32_to_cpu(bfs_sb->s_start) < BFS_BSIZE) {
 		printf("Superblock is corrupted\n");
 		goto out1;
 	}

@@ -359,9 +360,11 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
 					sizeof(struct bfs_inode)
 					+ BFS_ROOT_INO - 1;
 	imap_len = (info->si_lasti / 8) + 1;
-	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
-	if (!info->si_imap)
+	info->si_imap = kzalloc(imap_len, GFP_KERNEL | __GFP_NOWARN);
+	if (!info->si_imap) {
+		printf("Cannot allocate %u bytes\n", imap_len);
 		goto out1;
+	}
 	for (i = 0; i < BFS_ROOT_INO; i++)
 		set_bit(i, info->si_imap);
 

2.17.1

From: Jann Horn <[email protected]>

[ Upstream commit b10298d56c9623f9b173f19959732d3184b35f4f ]

fill_with_dentries() failed to propagate errors up to reiserfs_for_each_xattr() properly. Plumb them through.

Note that reiserfs_for_each_xattr() is only used by reiserfs_delete_xattrs() and reiserfs_chown_xattrs(). The result of reiserfs_delete_xattrs() is discarded anyway, the only difference there is whether a warning is printed to dmesg. The result of reiserfs_chown_xattrs() does matter because it can block chowning of the file to which the xattrs belong; but either way, the resulting state can have misaligned ownership, so my patch doesn't improve things greatly.

Credit for making me look at this code goes to Al Viro, who pointed out that the ->actor calling convention is suboptimal and should be changed.

---
 fs/reiserfs/xattr.c | 7 +++++++
 1 file changed, 7 insertions(+)

index 8b32fdaad468..d424b3d4bf3b 100644
@@ -184,6 +184,7 @@ struct reiserfs_dentry_buf {
 	struct dir_context ctx;
 	struct dentry *xadir;
 	int count;
+	int err;
 	struct dentry *dentries[8];
 };
 

@@ -206,6 +207,7 @@ fill_with_dentries(struct dir_context *ctx, const char *name, int namelen,
 
 	dentry = lookup_one_len(name, dbuf->xadir, namelen);
 	if (IS_ERR(dentry)) {
+		dbuf->err = PTR_ERR(dentry);
 		return PTR_ERR(dentry);
 	} else if (d_really_is_negative(dentry)) {
 		/* A directory entry exists, but no file? */

@@ -214,6 +216,7 @@ fill_with_dentries(struct dir_context *ctx, const char *name, int namelen,
 			       "not found for file %pd.\n",
 			       dentry, dbuf->xadir);
 		dput(dentry);
+		dbuf->err = -EIO;
 		return -EIO;
 	}
 

@@ -261,6 +264,10 @@ static int reiserfs_for_each_xattr(struct inode *inode,
 		err = reiserfs_readdir_inode(d_inode(dir), &buf.ctx);
 		if (err)
 			break;
+		if (buf.err) {
+			err = buf.err;
+			break;
+		}
 		if (!buf.count)
 			break;
 		for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) {

2.17.1

From: Ernesto A. Fernández <[email protected]>

[ Upstream commit d057c036672f33d43a5f7344acbb08cf3a8a0c09 ]

This bug is triggered whenever hfs_brec_update_parent() needs to split the root node. The height of the btree is not increased, which leaves the new node orphaned and its records lost. It is not possible for this to happen on a valid hfs filesystem because the index nodes have fixed length keys.

For reasons I ignore, the hfs module does have support for a number of hfsplus features. A corrupt btree header may report variable length keys and trigger this bug, so it's better to fix it.

---
 fs/hfs/brec.c | 4 ++++
 1 file changed, 4 insertions(+)

index 2a6f3c67cb3f..2e713673df42 100644
@@ -424,6 +424,10 @@ static int hfs_brec_update_parent(struct hfs_find_data *fd)
 	if (new_node) {
 		__be32 cnid;
 
+		if (!new_node->parent) {
+			hfs_btree_inc_height(tree);
+			new_node->parent = tree->root;
+		}
 		fd->bnode = hfs_bnode_find(tree, new_node->parent);
 		/* create index key and entry */
 		hfs_bnode_read_key(new_node, fd->search_key, 14);

2.17.1

From: Ernesto A. Fernández <[email protected]>

[ Upstream commit 0a3021d4f5295aa073c7bf5c5e4de60a2e292578 ]

Creating, renaming or deleting a file may cause catalog corruption and data loss. This bug is randomly triggered by xfstests generic/027, but here is a faster reproducer:

  truncate -s 50M fs.iso
  mkfs.hfsplus fs.iso
  mount fs.iso /mnt
  i=100
  while [ $i -le 150 ]; do
    touch /mnt/$i &>/dev/null
    ((++i))
  done
  i=100
  while [ $i -le 150 ]; do
    mv /mnt/$i /mnt/$(perl -e "print $i x82") &>/dev/null
    ((++i))
  done
  umount /mnt
  fsck.hfsplus -n fs.iso

The bug is triggered whenever hfs_brec_update_parent() needs to split the root node. The height of the btree is not increased, which leaves the new node orphaned and its records lost.

---
 fs/hfsplus/brec.c | 4 ++++
 1 file changed, 4 insertions(+)

index 754fdf8c6356..1002a0c08319 100644
@@ -427,6 +427,10 @@ static int hfs_brec_update_parent(struct hfs_find_data *fd)
 	if (new_node) {
 		__be32 cnid;
 
+		if (!new_node->parent) {
+			hfs_btree_inc_height(tree);
+			new_node->parent = tree->root;
+		}
 		fd->bnode = hfs_bnode_find(tree, new_node->parent);
 		/* create index key and entry */
 		hfs_bnode_read_key(new_node, fd->search_key, 14);

2.17.1

From: Richard Weinberger <[email protected]>

[ Upstream commit 7ff1e34bbdc15acab823b1ee4240e94623d50ee8 ]

Fixes:
arch/um/os-Linux/skas/process.c:613:1: warning: control reaches end of non-void function [-Wreturn-type]

longjmp() never returns but gcc still warns that the end of the function can be reached.
Add a return code and debug aid to detect this impossible case.

---
 arch/um/os-Linux/skas/process.c | 5 +++++
 1 file changed, 5 insertions(+)

index b856c66ebd3a..6dbf27ffafc8 100644
@@ -585,6 +585,11 @@ int start_idle_thread(void *stack, jmp_buf *switch_buf)
 		fatal_sigsegv();
 	}
 	longjmp(*switch_buf, 1);
+
+	/* unreachable */
+	printk(UM_KERN_ERR "impossible long jump!");
+	fatal_sigsegv();
+	return 0;
 }
 
 void initial_thread_cb_skas(void (*proc)(void *), void *arg)

2.17.1

From: Chengguang Xu <[email protected]>

[ Upstream commit 515f1867addaba49c1c6ac73abfaffbc192c1db4 ]

There are some cases can cause memory leak when parsing option 'osdname'.

---
 fs/exofs/super.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

index b795c567b5e1..360ba74e04e6 100644
@@ -100,6 +100,7 @@ static int parse_options(char *options, struct exofs_mountopt *opts)
 		token = match_token(p, tokens, args);
 		switch (token) {
 		case Opt_name:
+			kfree(opts->dev_name);
 			opts->dev_name = match_strdup(&args[0]);
 			if (unlikely(!opts->dev_name)) {
 				EXOFS_ERR("Error allocating dev_name");

@@ -868,8 +869,10 @@ static struct dentry *exofs_mount(struct file_system_type *type,
 	int ret;
 
 	ret = parse_options(data, &opts);
-	if (ret)
+	if (ret) {
+		kfree(opts.dev_name);
 		return ERR_PTR(ret);
+	}
 
 	if (!opts.dev_name)
 		opts.dev_name = dev_name;

2.17.1

From: Marek Szyprowski <[email protected]>

[ Upstream commit b33228029d842269e17bba591609e83ed422005d ]

Ensure that clocks for core SoC modules (including TZPC0..9 modules) are enabled for suspend/resume cycle. This fixes suspend/resume support on Exynos5422-based Odroid XU3/XU4 boards.

---
 drivers/clk/samsung/clk-exynos5420.c | 1 +
 1 file changed, 1 insertion(+)

index 389af3c15ec4..bde71b07f15e 100644
@@ -273,6 +273,7 @@ static const struct samsung_clk_reg_dump exynos5420_set_clksrc[] = {
 	{ .offset = GATE_BUS_TOP,		.value = 0xffffffff, },
 	{ .offset = GATE_BUS_DISP1,		.value = 0xffffffff, },
 	{ .offset = GATE_IP_PERIC,		.value = 0xffffffff, },
+	{ .offset = GATE_IP_PERIS,		.value = 0xffffffff, },
 };
 
 static int exynos5420_clk_suspend(void)

2.17.1

From: Paul Gortmaker <[email protected]>

[ Upstream commit 684238d79ad85c5e19a71bb5818e77e329912fbc ]

To fix:

acerhdf: unknown (unsupported) BIOS version Gateway /LT31 /v1.3307 , please report, aborting!

As can be seen in the context, the BIOS registers haven't changed in the previous versions, so the assumption is they won't have changed in this last update for this somewhat older platform either.

---
 drivers/platform/x86/acerhdf.c | 1 +
 1 file changed, 1 insertion(+)

index 460fa6708bfc..3c4b107aba78 100644
@@ -233,6 +233,7 @@ static const struct bios_settings bios_tbl[] = {
 	{"Gateway", "LT31",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
 	{"Gateway", "LT31",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
 	{"Gateway", "LT31",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
+	{"Gateway", "LT31",   "v1.3307",  0x55, 0x58, {0x9e, 0x00}, 0},
 	/* Packard Bell */
 	{"Packard Bell", "DOA150",  "v0.3104",  0x55, 0x58, {0x21, 0x00}, 0},
 	{"Packard Bell", "DOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},

2.17.1

From: Nathan Chancellor <[email protected]>

[ Upstream commit b5bb425871186303e6936fa2581521bdd1964a58 ]

Clang warns that if the default case is taken, ret will be uninitialized.

./arch/arm64/include/asm/percpu.h:196:2: warning: variable 'ret' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]

        default:
        ^~~~~~~
./arch/arm64/include/asm/percpu.h:200:9: note: uninitialized use occurs
here
        return ret;
               ^~~
./arch/arm64/include/asm/percpu.h:157:19: note: initialize the variable
'ret' to silence this warning
        unsigned long ret, loop;
                         ^
                          = 0

This warning appears several times while building the erofs filesystem. While it's not strictly wrong, the BUILD_BUG will prevent this from becoming a true problem. Initialize ret to 0 in the default case right before the BUILD_BUG to silence all of these warnings.

---
 arch/arm64/include/asm/percpu.h | 3 +++
 1 file changed, 3 insertions(+)

index 8a336852eeba..aea904713d0f 100644
@@ -84,6 +84,7 @@ static inline unsigned long __percpu_##op(void *ptr,			\
 		: [val] "Ir" (val));					\
 		break;							\
 	default:							\
+		ret = 0;						\
 		BUILD_BUG();						\
 	}								\
 									\

@@ -113,6 +114,7 @@ static inline unsigned long __percpu_read(void *ptr, int size)
 		ret = ACCESS_ONCE(*(u64 *)ptr);
 		break;
 	default:
+		ret = 0;
 		BUILD_BUG();
 	}
 

@@ -182,6 +184,7 @@ static inline unsigned long __percpu_xchg(void *ptr, unsigned long val,
 		: [val] "r" (val));
 		break;
 	default:
+		ret = 0;
 		BUILD_BUG();
 	}
 

2.17.1

From: Jann Horn <[email protected]>

[ Upstream commit f0ecf25a093fc0589f0a6bc4c1ea068bbb67d220 ]

Having two gigantic arrays that must manually be kept in sync, including ifdefs, isn't exactly robust. To make it easier to catch such issues in the future, add a BUILD_BUG_ON().

---
 mm/vmstat.c | 2 ++
 1 file changed, 2 insertions(+)

index a2d70ef74db7..a32a92c0f218 100644
@@ -1320,6 +1320,8 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos)
 	stat_items_size += sizeof(struct vm_event_state);
 #endif
 
+	BUILD_BUG_ON(stat_items_size !=
+		     ARRAY_SIZE(vmstat_text) * sizeof(unsigned long));
 	v = kmalloc(stat_items_size, GFP_KERNEL);
 	m->private = v;
 	if (!v)

2.17.1

From: Dmitry Vyukov <[email protected]>

[ Upstream commit 61448479a9f2c954cde0cfe778cb6bec5d0a748d ]

Slub does not call kmalloc_slab() for sizes > KMALLOC_MAX_CACHE_SIZE, instead it falls back to kmalloc_large().

For slab KMALLOC_MAX_CACHE_SIZE == KMALLOC_MAX_SIZE and it calls kmalloc_slab() for all allocations relying on NULL return value for over-sized allocations.

This inconsistency leads to unwanted warnings from kmalloc_slab() for over-sized allocations for slab. Returning NULL for failed allocations is the expected behavior.

Make slub and slab code consistent by checking size > KMALLOC_MAX_CACHE_SIZE in slab before calling kmalloc_slab().

While we are here also fix the check in kmalloc_slab(). We should check against KMALLOC_MAX_CACHE_SIZE rather than KMALLOC_MAX_SIZE. It all kinda worked because for slab the constants are the same, and slub always checks the size against KMALLOC_MAX_CACHE_SIZE before kmalloc_slab(). But if we get there with size > KMALLOC_MAX_CACHE_SIZE anyhow bad things will happen. For example, in case of a newly introduced bug in slub code.

Also move the check in kmalloc_slab() from function entry to the size > 192 case. This partially compensates for the additional check in slab code and makes slub code a bit faster (at least theoretically).

Also drop __GFP_NOWARN in the warning check. This warning means a bug in slab code itself, user-passed flags have nothing to do with it.

Nothing of this affects slob.

---
 mm/slab.c        |  4 ++++
 mm/slab_common.c | 12 ++++++------
 2 files changed, 10 insertions(+), 6 deletions(-)

index fa49c01225a7..49a64b8c3606 100644
@@ -3488,6 +3488,8 @@ __do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller)
 {
 	struct kmem_cache *cachep;
 
+	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
+		return NULL;
 	cachep = kmalloc_slab(size, flags);
 	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
 		return cachep;

@@ -3520,6 +3522,8 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
 	struct kmem_cache *cachep;
 	void *ret;
 
+	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
+		return NULL;
 	cachep = kmalloc_slab(size, flags);
 	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
 		return cachep;

index 01e7246de8df..2e7c960d6a06 100644
@@ -852,18 +852,18 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
 {
 	int index;
 
-	if (unlikely(size > KMALLOC_MAX_SIZE)) {
-		WARN_ON_ONCE(!(flags & __GFP_NOWARN));
-		return NULL;
-	}
-
 	if (size <= 192) {
 		if (!size)
 			return ZERO_SIZE_PTR;
 
 		index = size_index[size_index_elem(size)];
-	} else
+	} else {
+		if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
+			WARN_ON(1);
+			return NULL;
+		}
 		index = fls(size - 1);
+	}
 
 #ifdef CONFIG_ZONE_DMA
 	if (unlikely((flags & GFP_DMA)))

2.17.1