[PATCH v2] erofs: Prevent entering an infinite loop when i is 0

[liujinbao1]

From: liujinbao1 <liujinbao1 at xiaomi.com>

When i=0 and err is not equal to 0,
the while(-1) loop will enter into an
infinite loop. This patch avoids this issue

Signed-off-by: liujinbao1 <liujinbao1 at xiaomi.com>
---
 fs/erofs/decompressor.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index c2253b6a5416..672f097966fa 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -534,18 +534,18 @@ int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb)
 
 int __init z_erofs_init_decompressor(void)
 {
-	int i, err;
+	int i, err = 0;
 
 	for (i = 0; i < Z_EROFS_COMPRESSION_MAX; ++i) {
 		err = z_erofs_decomp[i] ? z_erofs_decomp[i]->init() : 0;
-		if (err) {
-			while (--i)
+		if (err && i) {
+			while (i--)
 				if (z_erofs_decomp[i])
 					z_erofs_decomp[i]->exit();
-			return err;
+			break;
 		}
 	}
-	return 0;
+	return err;
 }

(1) The use of "break" is to enable a jump out of the for loop, 
otherwise it may not be able to exit the loop.
(2) --i should be changed to i-- because when i is equal to 1,
the "while (--i)" statement would exit the loop prematurely.

and sorry for the delay in the response.