From: Dave Chinner dchinner@redhat.com
stable inclusion from stable-v5.10.145 commit dce466286944389dd77b314e0d1eea6969d0e4d4 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I685FC CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=t...
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commit 1eb70f54c445fcbb25817841e774adb3d912f3e8 upstream.
[backport for 5.10.y]
xfs_repair catches fork size/format mismatches, but the in-kernel verifier doesn't, leading to null pointer failures when attempting to perform operations on the fork. This can occur in the xfs_dir_is_empty() where the in-memory fork format does not match the size and so the fork data pointer is accessed incorrectly.
Note: this causes new failures in xfs/348 which is testing mode vs ftype mismatches. We now detect a regular file that has been changed to a directory or symlink mode as being corrupt because the data fork is for a symlink or directory should be in local form when there are only 3 bytes of data in the data fork. Hence the inode verify for the regular file now fires w/ -EFSCORRUPTED because the inode fork format does not match the format the corrupted mode says it should be in.
Signed-off-by: Dave Chinner dchinner@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Dave Chinner david@fromorbit.com Signed-off-by: Amir Goldstein amir73il@gmail.com Acked-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Long Li leo.lilong@huawei.com --- fs/xfs/libxfs/xfs_inode_buf.c | 35 ++++++++++++++++++++++++++--------- 1 file changed, 26 insertions(+), 9 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c index 4b247577fdc6..6095b3d7fb2d 100644 --- a/fs/xfs/libxfs/xfs_inode_buf.c +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -357,19 +357,36 @@ xfs_dinode_verify_fork( int whichfork) { uint32_t di_nextents = XFS_DFORK_NEXTENTS(dip, whichfork); + mode_t mode = be16_to_cpu(dip->di_mode); + uint32_t fork_size = XFS_DFORK_SIZE(dip, mp, whichfork); + uint32_t fork_format = XFS_DFORK_FORMAT(dip, whichfork);
- switch (XFS_DFORK_FORMAT(dip, whichfork)) { + /* + * For fork types that can contain local data, check that the fork + * format matches the size of local data contained within the fork. + * + * For all types, check that when the size says the should be in extent + * or btree format, the inode isn't claiming it is in local format. + */ + if (whichfork == XFS_DATA_FORK) { + if (S_ISDIR(mode) || S_ISLNK(mode)) { + if (be64_to_cpu(dip->di_size) <= fork_size && + fork_format != XFS_DINODE_FMT_LOCAL) + return __this_address; + } + + if (be64_to_cpu(dip->di_size) > fork_size && + fork_format == XFS_DINODE_FMT_LOCAL) + return __this_address; + } + + switch (fork_format) { case XFS_DINODE_FMT_LOCAL: /* - * no local regular files yet + * No local regular files yet. */ - if (whichfork == XFS_DATA_FORK) { - if (S_ISREG(be16_to_cpu(dip->di_mode))) - return __this_address; - if (be64_to_cpu(dip->di_size) > - XFS_DFORK_SIZE(dip, mp, whichfork)) - return __this_address; - } + if (S_ISREG(mode) && whichfork == XFS_DATA_FORK) + return __this_address; if (di_nextents) return __this_address; break;