在 2021/6/21 23:22, Colin King 写道:
From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
An earlier fix to replace an IS_ERR check on lp with a null check
on lp didn't remove a following null check on lp. The second null
check is redundant and can be removed.
Addresses-Coverity: ("Logically dead code")
Fixes: c770cd5190ba ("ubifs: fix an IS_ERR() vs NULL check")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
fs/ubifs/gc.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index 7cc22d7317ea..465beea52176 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -899,8 +899,6 @@ int ubifs_gc_start_commit(struct ubifs_info *c)
err = -ENOMEM;
goto out;
}
Hi Colin,
I just found out about it today thanks to your patch. Commit
c770cd5190ba ("ubifs: fix an IS_ERR() vs NULL check") did import a new
problem that ubifs_gc_start_commit() may return -ENOMEM while syncing fs.
I guess ubifs_fast_find_frdi_idx() return NULL pointer is the
termination condition in while-loop, which means we cannot get a
freeable index LEB in ubifs_gc_start_commit().
- if (!lp)
- break;
idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
if (!idx_gc) {
err = -ENOMEM;
BTW, the following modifications may be what you want?
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index 7cc22d7317ea..b1f276599b04 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -895,10 +895,6 @@ int ubifs_gc_start_commit(struct ubifs_info *c)
/* Record index freeable LEBs for unmapping after commit */
while (1) {
lp = ubifs_fast_find_frdi_idx(c);
- if (!lp) {
- err = -ENOMEM;
- goto out;
- }
if (!lp)
break;
idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb),
GFP_NOFS);
