UBIFS: fix oops in lprops dump function
The 'dbg_dump_lprop()' is trying to detect journal head LEBs when printing,
so it looks at the write-buffers. However, if we are in R/O mode, we
de-allocate the write-buffers, so 'dbg_dump_lprop()' oopses. This patch fixes
the issue.
Note, this patch is not critical, it is only about the debugging code path, and
it is unlikely that anyone but UBIFS developers would ever hit this issue.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index ba4d795..4062ec6 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -746,7 +746,13 @@
if (bud->lnum == lp->lnum) {
int head = 0;
for (i = 0; i < c->jhead_cnt; i++) {
- if (lp->lnum == c->jheads[i].wbuf.lnum) {
+ /*
+ * Note, if we are in R/O mode or in the middle
+ * of mounting/re-mounting, the write-buffers do
+ * not exist.
+ */
+ if (c->jheads &&
+ lp->lnum == c->jheads[i].wbuf.lnum) {
printk(KERN_CONT ", jhead %s",
dbg_jhead(i));
head = 1;