4.17-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jaegeuk Kim jaegeuk@kernel.org
commit 5d64600d4f337dc2bb89cd59da99f452f5e4f3c3 upstream.
syzbot has tested the proposed patch but the reproducer still triggered crash: kernel BUG at fs/f2fs/inode.c:LINE!
F2FS-fs (loop1): invalid crc value F2FS-fs (loop5): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop5): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop5): invalid crc value ------------[ cut here ]------------ kernel BUG at fs/f2fs/inode.c:238! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 4886 Comm: syz-executor1 Not tainted 4.17.0-rc1+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:do_read_inode fs/f2fs/inode.c:238 [inline] RIP: 0010:f2fs_iget+0x3307/0x3ca0 fs/f2fs/inode.c:313 RSP: 0018:ffff8801c44a70e8 EFLAGS: 00010293 RAX: ffff8801ce208040 RBX: ffff8801b3621080 RCX: ffffffff82eace18 F2FS-fs (loop2): Magic Mismatch, valid(0xf2f52010) - read(0x0) RDX: 0000000000000000 RSI: ffffffff82eaf047 RDI: 0000000000000007 RBP: ffff8801c44a7410 R08: ffff8801ce208040 R09: ffffed0039ee4176 R10: ffffed0039ee4176 R11: ffff8801cf720bb7 R12: ffff8801c0efa000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f753aa9d700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 ------------[ cut here ]------------ CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel BUG at fs/f2fs/inode.c:238! CR2: 0000000001b03018 CR3: 00000001c8b74000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_fill_super+0x4377/0x7bf0 fs/f2fs/super.c:2842 mount_bdev+0x30c/0x3e0 fs/super.c:1165 f2fs_mount+0x34/0x40 fs/f2fs/super.c:3020 mount_fs+0xae/0x328 fs/super.c:1268 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2517 [inline] do_mount+0x564/0x3070 fs/namespace.c:2847 ksys_mount+0x12d/0x140 fs/namespace.c:3063 __do_sys_mount fs/namespace.c:3077 [inline] __se_sys_mount fs/namespace.c:3074 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3074 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457daa RSP: 002b:00007f753aa9cba8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000000 RCX: 0000000000457daa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f753aa9cbf0 RBP: 0000000000000064 R08: 0000000020016a00 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000064 R14: 00000000006fcb80 R15: 0000000000000000 RIP: do_read_inode fs/f2fs/inode.c:238 [inline] RSP: ffff8801c44a70e8 RIP: f2fs_iget+0x3307/0x3ca0 fs/f2fs/inode.c:313 RSP: ffff8801c44a70e8 invalid opcode: 0000 [#2] SMP KASAN ---[ end trace 1cbcbec2156680bc ]---
Reported-and-tested-by: syzbot+41a1b341571f0952badb@syzkaller.appspotmail.com Reviewed-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/inode.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
--- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -185,6 +185,21 @@ void f2fs_inode_chksum_set(struct f2fs_s ri->i_inode_checksum = cpu_to_le32(f2fs_inode_chksum(sbi, page)); }
+static bool sanity_check_inode(struct inode *inode) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + + if (f2fs_sb_has_flexible_inline_xattr(sbi->sb) + && !f2fs_has_extra_attr(inode)) { + set_sbi_flag(sbi, SBI_NEED_FSCK); + f2fs_msg(sbi->sb, KERN_WARNING, + "%s: corrupted inode ino=%lx, run fsck to fix.", + __func__, inode->i_ino); + return false; + } + return true; +} + static int do_read_inode(struct inode *inode) { struct f2fs_sb_info *sbi = F2FS_I_SB(inode); @@ -235,7 +250,6 @@ static int do_read_inode(struct inode *i le16_to_cpu(ri->i_extra_isize) : 0;
if (f2fs_sb_has_flexible_inline_xattr(sbi->sb)) { - f2fs_bug_on(sbi, !f2fs_has_extra_attr(inode)); fi->i_inline_xattr_size = le16_to_cpu(ri->i_inline_xattr_size); } else if (f2fs_has_inline_xattr(inode) || f2fs_has_inline_dentry(inode)) { @@ -313,6 +327,10 @@ struct inode *f2fs_iget(struct super_blo ret = do_read_inode(inode); if (ret) goto bad_inode; + if (!sanity_check_inode(inode)) { + ret = -EINVAL; + goto bad_inode; + } make_now: if (ino == F2FS_NODE_INO(sbi)) { inode->i_mapping->a_ops = &f2fs_node_aops;