The patch titled
jffs2: fix race condition in jffs2_lzo_compress()
has been removed from the -mm tree. Its filename was
jffs2-fix-race-condition-in-jffs2_lzo_compress.patch
This patch was dropped because it was merged into mainline or a subsystem tree
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: jffs2: fix race condition in jffs2_lzo_compress()
From: Geert Uytterhoeven <Geert.Uytterhoeven@xxxxxxxxxxx>
deflate_mutex protects the globals lzo_mem and lzo_compress_buf. However,
jffs2_lzo_compress() unlocks deflate_mutex _before_ it has copied out the
compressed data from lzo_compress_buf. Correct this by moving the mutex
unlock after the copy.
In addition, document what deflate_mutex actually protects.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@xxxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Acked-by: Richard Purdie <rpurdie@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/jffs2/compr_lzo.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
diff -puN fs/jffs2/compr_lzo.c~jffs2-fix-race-condition-in-jffs2_lzo_compress fs/jffs2/compr_lzo.c
--- a/fs/jffs2/compr_lzo.c~jffs2-fix-race-condition-in-jffs2_lzo_compress
+++ a/fs/jffs2/compr_lzo.c
@@ -19,7 +19,7 @@
static void *lzo_mem;
static void *lzo_compress_buf;
-static DEFINE_MUTEX(deflate_mutex);
+static DEFINE_MUTEX(deflate_mutex); /* for lzo_mem and lzo_compress_buf */
static void free_workspace(void)
{
@@ -49,18 +49,21 @@ static int jffs2_lzo_compress(unsigned c
mutex_lock(&deflate_mutex);
ret = lzo1x_1_compress(data_in, *sourcelen, lzo_compress_buf, &compress_size, lzo_mem);
- mutex_unlock(&deflate_mutex);
-
if (ret != LZO_E_OK)
- return -1;
+ goto fail;
if (compress_size > *dstlen)
- return -1;
+ goto fail;
memcpy(cpage_out, lzo_compress_buf, compress_size);
- *dstlen = compress_size;
+ mutex_unlock(&deflate_mutex);
+ *dstlen = compress_size;
return 0;
+
+ fail:
+ mutex_unlock(&deflate_mutex);
+ return -1;
}
static int jffs2_lzo_decompress(unsigned char *data_in, unsigned char *cpage_out,
_
Patches currently in -mm which might be from Geert.Uytterhoeven@xxxxxxxxxxx are
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