From 21ec68234826b1b54ab980a8df6e33c74cfbee58 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Wed, 24 Jan 2024 22:49:15 +0800 Subject: [PATCH] f2fs: fix to avoid potential panic during recovery During recovery, if FAULT_BLOCK is on, it is possible that f2fs_reserve_new_block() will return -ENOSPC during recovery, then it may trigger panic. Also, if fault injection rate is 1 and only FAULT_BLOCK fault type is on, it may encounter deadloop in loop of block reservation. Let's change as below to fix these issues: - remove bug_on() to avoid panic. - limit the loop count of block reservation to avoid potential deadloop. Fixes: 956fa1ddc132 ("f2fs: fix to check return value of f2fs_reserve_new_block()") Reported-by: Zhiguo Niu Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/f2fs.h | 5 +++++ fs/f2fs/recovery.c | 33 ++++++++++++++++----------------- 2 files changed, 21 insertions(+), 17 deletions(-) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 40d428636532..543898482f8b 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -76,6 +76,11 @@ struct f2fs_fault_info { extern const char *f2fs_fault_name[FAULT_MAX]; #define IS_FAULT_SET(fi, type) ((fi)->inject_type & BIT(type)) + +/* maximum retry count for injected failure */ +#define DEFAULT_FAILURE_RETRY_COUNT 8 +#else +#define DEFAULT_FAILURE_RETRY_COUNT 1 #endif /* diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index d0f24ccbd1ac..aad1d1a9b3d6 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -611,6 +611,19 @@ truncate_out: return 0; } +static int f2fs_reserve_new_block_retry(struct dnode_of_data *dn) +{ + int i, err = 0; + + for (i = DEFAULT_FAILURE_RETRY_COUNT; i > 0; i--) { + err = f2fs_reserve_new_block(dn); + if (!err) + break; + } + + return err; +} + static int do_recover_data(struct f2fs_sb_info *sbi, struct inode *inode, struct page *page) { @@ -712,14 +725,8 @@ retry_dn: */ if (dest == NEW_ADDR) { f2fs_truncate_data_blocks_range(&dn, 1); - do { - err = f2fs_reserve_new_block(&dn); - if (err == -ENOSPC) { - f2fs_bug_on(sbi, 1); - break; - } - } while (err && - IS_ENABLED(CONFIG_F2FS_FAULT_INJECTION)); + + err = f2fs_reserve_new_block_retry(&dn); if (err) goto err; continue; @@ -727,16 +734,8 @@ retry_dn: /* dest is valid block, try to recover from src to dest */ if (f2fs_is_valid_blkaddr(sbi, dest, META_POR)) { - if (src == NULL_ADDR) { - do { - err = f2fs_reserve_new_block(&dn); - if (err == -ENOSPC) { - f2fs_bug_on(sbi, 1); - break; - } - } while (err && - IS_ENABLED(CONFIG_F2FS_FAULT_INJECTION)); + err = f2fs_reserve_new_block_retry(&dn); if (err) goto err; } -- 2.20.1