From: Yangtao Li frank.li@vivo.com
[ Upstream commit 0dbbf0fb38d5ec5d4138d1aeaeb43d9217b9a592 ]
Add iotype sanity check to avoid potential memory corruption. This is to fix the compile error below:
fs/f2fs/iostat.c:231 __update_iostat_latency() error: buffer overflow 'io_lat->peak_lat[type]' 3 <= 3
vim +228 fs/f2fs/iostat.c
211 static inline void __update_iostat_latency(struct bio_iostat_ctx *iostat_ctx, 212 enum iostat_lat_type type) 213 { 214 unsigned long ts_diff; 215 unsigned int page_type = iostat_ctx->type; 216 struct f2fs_sb_info *sbi = iostat_ctx->sbi; 217 struct iostat_lat_info *io_lat = sbi->iostat_io_lat; 218 unsigned long flags; 219 220 if (!sbi->iostat_enable) 221 return; 222 223 ts_diff = jiffies - iostat_ctx->submit_ts; 224 if (page_type >= META_FLUSH) ^^^^^^^^^^
225 page_type = META; 226 227 spin_lock_irqsave(&sbi->iostat_lat_lock, flags); @228 io_lat->sum_lat[type][page_type] += ts_diff; ^^^^^^^^^ Mixup between META_FLUSH and NR_PAGE_TYPE leads to memory corruption.
Fixes: a4b6817625e7 ("f2fs: introduce periodic iostat io latency traces") Reported-by: kernel test robot lkp@intel.com Reported-by: Dan Carpenter error27@gmail.com Suggested-by: Chao Yu chao@kernel.org Suggested-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Yangtao Li frank.li@vivo.com Reviewed-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/iostat.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/fs/f2fs/iostat.c b/fs/f2fs/iostat.c index 3166a8939ed4f..02393c95c9f86 100644 --- a/fs/f2fs/iostat.c +++ b/fs/f2fs/iostat.c @@ -227,8 +227,12 @@ static inline void __update_iostat_latency(struct bio_iostat_ctx *iostat_ctx, return;
ts_diff = jiffies - iostat_ctx->submit_ts; - if (iotype >= META_FLUSH) + if (iotype == META_FLUSH) { iotype = META; + } else if (iotype >= NR_PAGE_TYPE) { + f2fs_warn(sbi, "%s: %d over NR_PAGE_TYPE", __func__, iotype); + return; + }
if (rw == 0) { idx = READ_IO;