From: Theodore Ts'o Date: Tue, 2 Jun 2009 12:07:54 +0000 (-0400) Subject: ext4: Fix softlockup caused by illegal i_file_acl value in on-disk inode X-Git-Tag: v2.6.29.5~6 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8c30ec0c2f7a507e960bba4113e59f31fa4a42fc;p=thirdparty%2Fkernel%2Fstable.git ext4: Fix softlockup caused by illegal i_file_acl value in on-disk inode (cherry picked from commit 485c26ec70f823f2a9cf45982b724893e53a859e) If the block containing external extended attributes (which is stored in i_file_acl and i_file_acl_high) is larger than the on-disk filesystem, the process which tried to access the extended attributes will endlessly issue kernel printks complaining that "__find_get_block_slow() failed", locking up that CPU until the system is forcibly rebooted. So when we read in the inode, make sure the i_file_acl value is legal, and if not, flag the filesystem as being corrupted. Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 9f898fd3b5ca8..269b1c829b07a 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4351,6 +4351,18 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino) (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; } + if (ei->i_file_acl && + ((ei->i_file_acl < + (le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) + + EXT4_SB(sb)->s_gdb_count)) || + (ei->i_file_acl >= ext4_blocks_count(EXT4_SB(sb)->s_es)))) { + ext4_error(sb, __func__, + "bad extended attribute block %llu in inode #%lu", + ei->i_file_acl, inode->i_ino); + ret = -EIO; + goto bad_inode; + } + if (S_ISREG(inode->i_mode)) { inode->i_op = &ext4_file_inode_operations; inode->i_fop = &ext4_file_operations;