From edaa0a0aab6e63b2ea7747f14daa68808ea4f36b Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Wed, 20 Jan 2021 09:30:16 +0800 Subject: [PATCH] erofs: fix shift-out-of-bounds of blkszbits commit bde545295b710bdd13a0fcd4b9fddd2383eeeb3a upstream. syzbot generated a crafted bitszbits which can be shifted out-of-bounds[1]. So directly print unsupported blkszbits instead of blksize. [1] https://lore.kernel.org/r/000000000000c72ddd05b9444d2f@google.com Link: https://lore.kernel.org/r/20210120013016.14071-1-hsiangkao@aol.com Reported-by: syzbot+c68f467cd7c45860e8d4@syzkaller.appspotmail.com Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Signed-off-by: Greg Kroah-Hartman --- fs/erofs/super.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 0e369494f2f2..22e059b4f745 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -124,8 +124,8 @@ static int erofs_read_superblock(struct super_block *sb) blkszbits = dsb->blkszbits; /* 9(512 bytes) + LOG_SECTORS_PER_BLOCK == LOG_BLOCK_SIZE */ if (blkszbits != LOG_BLOCK_SIZE) { - erofs_err(sb, "blksize %u isn't supported on this platform", - 1 << blkszbits); + erofs_err(sb, "blkszbits %u isn't supported on this platform", + blkszbits); goto out; }