From: Chao Yu yuchao0@huawei.com
commit e584bbe821229a3e7cc409eecd51df66f9268c21 upstream.
syzbot reported a bug which could cause shift-out-of-bounds issue, fix it.
Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:395 sanity_check_raw_super fs/f2fs/super.c:2812 [inline] read_raw_super_block fs/f2fs/super.c:3267 [inline] f2fs_fill_super.cold+0x16c9/0x16f6 fs/f2fs/super.c:3519 mount_bdev+0x34d/0x410 fs/super.c:1366 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1496 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported-by: syzbot+ca9a785f8ac472085994@syzkaller.appspotmail.com Signed-off-by: Anant Thazhemadam anant.thazhemadam@gmail.com Signed-off-by: Chao Yu yuchao0@huawei.com Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/f2fs/super.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
--- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -2744,7 +2744,6 @@ static int sanity_check_raw_super(struct block_t total_sections, blocks_per_seg; struct f2fs_super_block *raw_super = (struct f2fs_super_block *) (bh->b_data + F2FS_SUPER_OFFSET); - unsigned int blocksize; size_t crc_offset = 0; __u32 crc = 0;
@@ -2778,10 +2777,10 @@ static int sanity_check_raw_super(struct }
/* Currently, support only 4KB block size */ - blocksize = 1 << le32_to_cpu(raw_super->log_blocksize); - if (blocksize != F2FS_BLKSIZE) { - f2fs_info(sbi, "Invalid blocksize (%u), supports only 4KB", - blocksize); + if (le32_to_cpu(raw_super->log_blocksize) != F2FS_BLKSIZE_BITS) { + f2fs_info(sbi, "Invalid log_blocksize (%u), supports only %u", + le32_to_cpu(raw_super->log_blocksize), + F2FS_BLKSIZE_BITS); return -EFSCORRUPTED; }