From a64d9493f587f8ec101d92ec19c7d88d6d3b5567 Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Sun, 18 Aug 2019 18:28:24 +0800 Subject: [PATCH] staging: erofs: refuse to mount images with malformed volume name As Richard reminder [1], A valid volume name should be ended in NIL terminator within the length of volume_name. Since this field currently isn't really used, let's fix it to avoid potential bugs in the future. [1] https://lore.kernel.org/r/1133002215.69049.1566119033047.JavaMail.zimbra@nod.at/ Reported-by: Richard Weinberger Signed-off-by: Gao Xiang Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20190818102824.22330-1-hsiangkao@aol.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/erofs/super.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c index f65a1ff9f42f..2da471010a86 100644 --- a/drivers/staging/erofs/super.c +++ b/drivers/staging/erofs/super.c @@ -131,9 +131,14 @@ static int superblock_read(struct super_block *sb) sbi->build_time_nsec = le32_to_cpu(layout->build_time_nsec); memcpy(&sb->s_uuid, layout->uuid, sizeof(layout->uuid)); - memcpy(sbi->volume_name, layout->volume_name, - sizeof(layout->volume_name)); + ret = strscpy(sbi->volume_name, layout->volume_name, + sizeof(layout->volume_name)); + if (ret < 0) { /* -E2BIG */ + errln("bad volume name without NIL terminator"); + ret = -EFSCORRUPTED; + goto out; + } ret = 0; out: brelse(bh); -- 2.11.0