1 files changed, 50 insertions, 18 deletions
diff --git a/fs/romfs/storage.c b/fs/romfs/storage.c
index 7e3e1e12a081..b3208adf8e71 100644
--- a/fs/romfs/storage.c
+++ b/fs/romfs/storage.c
@@ -67,26 +67,35 @@ static ssize_t romfs_mtd_strnlen(struct super_block *sb,
 * compare a string to one in a romfs image on MTD
 * - return 1 if matched, 0 if differ, -ve if error
 */
-static int romfs_mtd_strncmp(struct super_block *sb, unsigned long pos,
+static int romfs_mtd_strcmp(struct super_block *sb, unsigned long pos,
-                             const char *str, size_t size)
+                            const char *str, size_t size)
 {
-        u_char buf[16];
+        u_char buf[17];
        size_t len, segment;
        int ret;
-        /* scan the string up to 16 bytes at a time */
+        /* scan the string up to 16 bytes at a time, and attempt to grab the
+         * trailing NUL whilst we're at it */
+        buf[0] = 0xff;
        while (size > 0) {
-                segment = min_t(size_t, size, 16);
+                segment = min_t(size_t, size + 1, 17);
                ret = ROMFS_MTD_READ(sb, pos, segment, &len, buf);
                if (ret < 0)
                        return ret;
+                len--;
                if (memcmp(buf, str, len) != 0)
                        return 0;
+                buf[0] = buf[len];
                size -= len;
                pos += len;
                str += len;
        }
+        /* check the trailing NUL was */
+        if (buf[0])
+                return 0;
        return 1;
 }
 #endif /* CONFIG_ROMFS_ON_MTD */
@@ -111,6 +120,7 @@ static int romfs_blk_read(struct super_block *sb, unsigned long pos,
                        return -EIO;
                memcpy(buf, bh->b_data + offset, segment);
                brelse(bh);
+                buf += segment;
                buflen -= segment;
                pos += segment;
        }
@@ -154,28 +164,48 @@ static ssize_t romfs_blk_strnlen(struct super_block *sb,
 * compare a string to one in a romfs image on a block device
 * - return 1 if matched, 0 if differ, -ve if error
 */
-static int romfs_blk_strncmp(struct super_block *sb, unsigned long pos,
+static int romfs_blk_strcmp(struct super_block *sb, unsigned long pos,
-                             const char *str, size_t size)
+                            const char *str, size_t size)
 {
        struct buffer_head *bh;
        unsigned long offset;
        size_t segment;
-        bool x;
+        bool matched, terminated = false;
-        /* scan the string up to 16 bytes at a time */
+        /* compare string up to a block at a time */
        while (size > 0) {
                offset = pos & (ROMBSIZE - 1);
                segment = min_t(size_t, size, ROMBSIZE - offset);
                bh = sb_bread(sb, pos >> ROMBSBITS);
                if (!bh)
                        return -EIO;
-                x = (memcmp(bh->b_data + offset, str, segment) != 0);
+                matched = (memcmp(bh->b_data + offset, str, segment) == 0);
-                brelse(bh);
-                if (x)
-                        return 0;
                size -= segment;
                pos += segment;
                str += segment;
+                if (matched && size == 0 && offset + segment < ROMBSIZE) {
+                        if (!bh->b_data[offset + segment])
+                                terminated = true;
+                        else
+                                matched = false;
+                }
+                brelse(bh);
+                if (!matched)
+                        return 0;
+        }
+        if (!terminated) {
+                /* the terminating NUL must be on the first byte of the next
+                 * block */
+                BUG_ON((pos & (ROMBSIZE - 1)) != 0);
+                bh = sb_bread(sb, pos >> ROMBSBITS);
+                if (!bh)
+                        return -EIO;
+                matched = !bh->b_data[0];
+                brelse(bh);
+                if (!matched)
+                        return 0;
        }
        return 1;
@@ -234,10 +264,12 @@ ssize_t romfs_dev_strnlen(struct super_block *sb,
 /*
 * compare a string to one in romfs
+ * - the string to be compared to, str, may not be NUL-terminated; instead the
+ *   string is of the specified size
 * - return 1 if matched, 0 if differ, -ve if error
 */
-int romfs_dev_strncmp(struct super_block *sb, unsigned long pos,
+int romfs_dev_strcmp(struct super_block *sb, unsigned long pos,
-                      const char *str, size_t size)
+                     const char *str, size_t size)
 {
        size_t limit;
@@ -246,16 +278,16 @@ int romfs_dev_strncmp(struct super_block *sb, unsigned long pos,
                return -EIO;
        if (size > ROMFS_MAXFN)
                return -ENAMETOOLONG;
-        if (size > limit - pos)
+        if (size + 1 > limit - pos)
                return -EIO;
 #ifdef CONFIG_ROMFS_ON_MTD
        if (sb->s_mtd)
-                return romfs_mtd_strncmp(sb, pos, str, size);
+                return romfs_mtd_strcmp(sb, pos, str, size);
 #endif
 #ifdef CONFIG_ROMFS_ON_BLOCK
        if (sb->s_bdev)
-                return romfs_blk_strncmp(sb, pos, str, size);
+                return romfs_blk_strcmp(sb, pos, str, size);
 #endif
        return -EIO;
 }

diff --git a/fs/romfs/storage.c b/fs/romfs/storage.c index 7e3e1e12a081..b3208adf8e71 100644 --- a/fs/romfs/storage.c +++ b/fs/romfs/storage.c
@@ -67,26 +67,35 @@ static ssize_t romfs_mtd_strnlen(struct super_block *sb,
67	* compare a string to one in a romfs image on MTD	67	* compare a string to one in a romfs image on MTD
68	* - return 1 if matched, 0 if differ, -ve if error	68	* - return 1 if matched, 0 if differ, -ve if error
69	*/	69	*/
70	static int romfs_mtd_strncmp(struct super_block *sb, unsigned long pos,	70	static int romfs_mtd_strcmp(struct super_block *sb, unsigned long pos,
71	const char *str, size_t size)	71	const char *str, size_t size)
72	{	72	{
73	u_char buf[16];	73	u_char buf[17];
74	size_t len, segment;	74	size_t len, segment;
75	int ret;	75	int ret;
76		76
77	/* scan the string up to 16 bytes at a time */	77	/* scan the string up to 16 bytes at a time, and attempt to grab the
		78	* trailing NUL whilst we're at it */
		79	buf[0] = 0xff;
		80
78	while (size > 0) {	81	while (size > 0) {
79	segment = min_t(size_t, size, 16);	82	segment = min_t(size_t, size + 1, 17);
80	ret = ROMFS_MTD_READ(sb, pos, segment, &len, buf);	83	ret = ROMFS_MTD_READ(sb, pos, segment, &len, buf);
81	if (ret < 0)	84	if (ret < 0)
82	return ret;	85	return ret;
		86	len--;
83	if (memcmp(buf, str, len) != 0)	87	if (memcmp(buf, str, len) != 0)
84	return 0;	88	return 0;
		89	buf[0] = buf[len];
85	size -= len;	90	size -= len;
86	pos += len;	91	pos += len;
87	str += len;	92	str += len;
88	}	93	}
89		94
		95	/* check the trailing NUL was */
		96	if (buf[0])
		97	return 0;
		98
90	return 1;	99	return 1;
91	}	100	}
92	#endif /* CONFIG_ROMFS_ON_MTD */	101	#endif /* CONFIG_ROMFS_ON_MTD */
@@ -111,6 +120,7 @@ static int romfs_blk_read(struct super_block *sb, unsigned long pos,
111	return -EIO;	120	return -EIO;
112	memcpy(buf, bh->b_data + offset, segment);	121	memcpy(buf, bh->b_data + offset, segment);
113	brelse(bh);	122	brelse(bh);
		123	buf += segment;
114	buflen -= segment;	124	buflen -= segment;
115	pos += segment;	125	pos += segment;
116	}	126	}
@@ -154,28 +164,48 @@ static ssize_t romfs_blk_strnlen(struct super_block *sb,
154	* compare a string to one in a romfs image on a block device	164	* compare a string to one in a romfs image on a block device
155	* - return 1 if matched, 0 if differ, -ve if error	165	* - return 1 if matched, 0 if differ, -ve if error
156	*/	166	*/
157	static int romfs_blk_strncmp(struct super_block *sb, unsigned long pos,	167	static int romfs_blk_strcmp(struct super_block *sb, unsigned long pos,
158	const char *str, size_t size)	168	const char *str, size_t size)
159	{	169	{
160	struct buffer_head *bh;	170	struct buffer_head *bh;
161	unsigned long offset;	171	unsigned long offset;
162	size_t segment;	172	size_t segment;
163	bool x;	173	bool matched, terminated = false;
164		174
165	/* scan the string up to 16 bytes at a time */	175	/* compare string up to a block at a time */
166	while (size > 0) {	176	while (size > 0) {
167	offset = pos & (ROMBSIZE - 1);	177	offset = pos & (ROMBSIZE - 1);
168	segment = min_t(size_t, size, ROMBSIZE - offset);	178	segment = min_t(size_t, size, ROMBSIZE - offset);
169	bh = sb_bread(sb, pos >> ROMBSBITS);	179	bh = sb_bread(sb, pos >> ROMBSBITS);
170	if (!bh)	180	if (!bh)
171	return -EIO;	181	return -EIO;
172	x = (memcmp(bh->b_data + offset, str, segment) != 0);	182	matched = (memcmp(bh->b_data + offset, str, segment) == 0);
173	brelse(bh);	183
174	if (x)
175	return 0;
176	size -= segment;	184	size -= segment;
177	pos += segment;	185	pos += segment;
178	str += segment;	186	str += segment;
		187	if (matched && size == 0 && offset + segment < ROMBSIZE) {
		188	if (!bh->b_data[offset + segment])
		189	terminated = true;
		190	else
		191	matched = false;
		192	}
		193	brelse(bh);
		194	if (!matched)
		195	return 0;
		196	}
		197
		198	if (!terminated) {
		199	/* the terminating NUL must be on the first byte of the next
		200	* block */
		201	BUG_ON((pos & (ROMBSIZE - 1)) != 0);
		202	bh = sb_bread(sb, pos >> ROMBSBITS);
		203	if (!bh)
		204	return -EIO;
		205	matched = !bh->b_data[0];
		206	brelse(bh);
		207	if (!matched)
		208	return 0;
179	}	209	}
180		210
181	return 1;	211	return 1;
@@ -234,10 +264,12 @@ ssize_t romfs_dev_strnlen(struct super_block *sb,
234		264
235	/*	265	/*
236	* compare a string to one in romfs	266	* compare a string to one in romfs
		267	* - the string to be compared to, str, may not be NUL-terminated; instead the
		268	* string is of the specified size
237	* - return 1 if matched, 0 if differ, -ve if error	269	* - return 1 if matched, 0 if differ, -ve if error
238	*/	270	*/
239	int romfs_dev_strncmp(struct super_block *sb, unsigned long pos,	271	int romfs_dev_strcmp(struct super_block *sb, unsigned long pos,
240	const char *str, size_t size)	272	const char *str, size_t size)
241	{	273	{
242	size_t limit;	274	size_t limit;
243		275
@@ -246,16 +278,16 @@ int romfs_dev_strncmp(struct super_block *sb, unsigned long pos,
246	return -EIO;	278	return -EIO;
247	if (size > ROMFS_MAXFN)	279	if (size > ROMFS_MAXFN)
248	return -ENAMETOOLONG;	280	return -ENAMETOOLONG;
249	if (size > limit - pos)	281	if (size + 1 > limit - pos)
250	return -EIO;	282	return -EIO;
251		283
252	#ifdef CONFIG_ROMFS_ON_MTD	284	#ifdef CONFIG_ROMFS_ON_MTD
253	if (sb->s_mtd)	285	if (sb->s_mtd)
254	return romfs_mtd_strncmp(sb, pos, str, size);	286	return romfs_mtd_strcmp(sb, pos, str, size);
255	#endif	287	#endif
256	#ifdef CONFIG_ROMFS_ON_BLOCK	288	#ifdef CONFIG_ROMFS_ON_BLOCK
257	if (sb->s_bdev)	289	if (sb->s_bdev)
258	return romfs_blk_strncmp(sb, pos, str, size);	290	return romfs_blk_strcmp(sb, pos, str, size);
259	#endif	291	#endif
260	return -EIO;	292	return -EIO;
261	}	293	}