[PATCH 3.4 008/107] hpfs: hpfs_error: Remove static buffer, use vsprintf extension %pV instead

lizf
2016-03-16T08:07:41Z

From: Joe Perches <joe@perches.com>

3.4.111-rc1 review patch. If anyone has any objections, please let me know.

------------------

commit a28e4b2b18ccb90df402da3f21e1a83c9d4f8ec1 upstream.

Removing unnecessary static buffers is good.
Use the vsprintf %pV extension instead.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Mikulas:
- The bug corrected by the patch is - if hpfs_error is called concurrently
on multiple filesystems, it could corrupt the string because the text
buffer is shared. That's why I marked the patch for stable.]
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
fs/hpfs/super.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c
index 0b990b2..efc1823 100644
--- a/fs/hpfs/super.c
+++ b/fs/hpfs/super.c
@@ -52,17 +52,20 @@ static void unmark_dirty(struct super_block *s)
}

/* Filesystem error... */
-static char err_buf[1024];
-
void hpfs_error(struct super_block *s, const char *fmt, ...)
{
+ struct va_format vaf;
va_list args;

va_start(args, fmt);
- vsnprintf(err_buf, sizeof(err_buf), fmt, args);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ pr_err("filesystem error: %pV", &vaf);
+
va_end(args);

- printk("HPFS: filesystem error: %s", err_buf);
if (!hpfs_sb(s)->sb_was_error) {
if (hpfs_sb(s)->sb_err == 2) {
printk("; crashing the system because you wanted it\n");
--
1.9.1