diff options
| author | Chao Yu <yuchao0@huawei.com> | 2017-08-07 23:12:46 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2017-08-15 10:40:14 -0700 |
| commit | b8c502b81e3f899c6488967dec61eed0f5907db3 (patch) | |
| tree | ec5f157c9804945eb46dc13b2fc3ab58d9e03bc6 | |
| parent | 9a20d391cd099d547c0f17626bf6f13e06da519a (diff) | |
f2fs: fix potential overflow when adjusting GC cycle
While comparing signed and unsigned variables, compiler will converts the
signed value to unsigned one, due to this reason, {in,de}crease_sleep_time
may return overflowed result.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| -rw-r--r-- | fs/f2fs/gc.c | 2 | ||||
| -rw-r--r-- | fs/f2fs/gc.h | 23 | ||||
| -rw-r--r-- | include/trace/events/f2fs.h | 6 |
3 files changed, 19 insertions, 12 deletions
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 8da7c14a9d29..e60480f71bb5 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -28,7 +28,7 @@ static int gc_thread_func(void *data) struct f2fs_sb_info *sbi = data; struct f2fs_gc_kthread *gc_th = sbi->gc_thread; wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head; - long wait_ms; + unsigned int wait_ms; wait_ms = gc_th->min_sleep_time; diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h index 57a9000ce3af..9325191fab2d 100644 --- a/fs/f2fs/gc.h +++ b/fs/f2fs/gc.h @@ -69,25 +69,32 @@ static inline block_t limit_free_user_blocks(struct f2fs_sb_info *sbi) } static inline void increase_sleep_time(struct f2fs_gc_kthread *gc_th, - long *wait) + unsigned int *wait) { + unsigned int min_time = gc_th->min_sleep_time; + unsigned int max_time = gc_th->max_sleep_time; + if (*wait == gc_th->no_gc_sleep_time) return; - *wait += gc_th->min_sleep_time; - if (*wait > gc_th->max_sleep_time) - *wait = gc_th->max_sleep_time; + if ((long long)*wait + (long long)min_time > (long long)max_time) + *wait = max_time; + else + *wait += min_time; } static inline void decrease_sleep_time(struct f2fs_gc_kthread *gc_th, - long *wait) + unsigned int *wait) { + unsigned int min_time = gc_th->min_sleep_time; + if (*wait == gc_th->no_gc_sleep_time) *wait = gc_th->max_sleep_time; - *wait -= gc_th->min_sleep_time; - if (*wait <= gc_th->min_sleep_time) - *wait = gc_th->min_sleep_time; + if ((long long)*wait - (long long)min_time < (long long)min_time) + *wait = min_time; + else + *wait -= min_time; } static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi) diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h index 6f77a2755abb..db5c98256147 100644 --- a/include/trace/events/f2fs.h +++ b/include/trace/events/f2fs.h @@ -543,14 +543,14 @@ TRACE_EVENT(f2fs_map_blocks, TRACE_EVENT(f2fs_background_gc, - TP_PROTO(struct super_block *sb, long wait_ms, + TP_PROTO(struct super_block *sb, unsigned int wait_ms, unsigned int prefree, unsigned int free), TP_ARGS(sb, wait_ms, prefree, free), TP_STRUCT__entry( __field(dev_t, dev) - __field(long, wait_ms) + __field(unsigned int, wait_ms) __field(unsigned int, prefree) __field(unsigned int, free) ), @@ -562,7 +562,7 @@ TRACE_EVENT(f2fs_background_gc, __entry->free = free; ), - TP_printk("dev = (%d,%d), wait_ms = %ld, prefree = %u, free = %u", + TP_printk("dev = (%d,%d), wait_ms = %u, prefree = %u, free = %u", show_dev(__entry->dev), __entry->wait_ms, __entry->prefree, |