When large extent counter / NREXT64 support was added to GRUB, it missed
a couple of direct reads of nextents which need to be changed to the new
NREXT64-aware helper as well. Without this, we'll have mis-reads of some
directories with this feature enabled.
The large extent counter fix likely raced on merge with commit 07318ee7e
(fs/xfs: Fix XFS directory extent parsing) which added the new direct
nextents reads just prior, causing this issue.
Fixes: aa7c1322671e (fs/xfs: Add large extent counters incompat feature support)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Jon DeVree <nuxi@vault24.org>
Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Commit ef7850c757 (fs/xfs: Fix issues found while fuzzing the XFS
filesystem) introduced multiple boundary checks in grub_xfs_iterate_dir()
but handled the error incorrectly returning error code instead of 0.
Fix it. Also change the error message so that it doesn't match the
message in grub_xfs_read_inode().
Fixes: ef7850c757 (fs/xfs: Fix issues found while fuzzing the XFS filesystem)
Signed-off-by: Egor Ignatov <egori@altlinux.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The Linux port of XFS added a few new features in 2024. The existing
GRUB driver doesn't attempt to read or write any of the new metadata,
so, all three can be added to the incompat allowlist.
On the occasion align XFS_SB_FEAT_INCOMPAT_NREXT64 value.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Replace direct arithmetic operations with macros from include/grub/safemath.h
to prevent potential overflow issues when calculating the memory sizes.
Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The grub_file_open() and grub_file_close() should be the only places
that allow a reference to a filesystem to stay open. So, add grub_dl_t
to grub_fs_t and set this in the GRUB_MOD_INIT() for each filesystem to
avoid issues when filesystems forget to do it themselves or do not track
their own references, e.g. squash4.
The fs_label(), fs_uuid(), fs_mtime() and fs_read() should all ref and
unref in the same function but it is essentially redundant in GRUB
single threaded model.
Signed-off-by: B Horn <b@horn.uk>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
It was previously possible for grub_xfs_mount() to return NULL without
setting grub_errno if the XFS version was invalid. This resulted in it
being possible for grub_dl_unref() to be called twice allowing the XFS
module to be unloaded while there were still references to it.
Fixing this problem in general by ensuring a grub_errno is set if the
fail label is reached.
Reported-by: B Horn <b@horn.uk>
Signed-off-by: B Horn <b@horn.uk>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The number of records in the root key array read from disk was not being
validated against the size of the root node. This could lead to an
out-of-bounds read.
This patch adds a check to ensure that the number of records in the root
key array does not exceed the expected size of a root node read from
disk. If this check detects an out-of-bounds condition the operation is
aborted to prevent random errors due to metadata corruption.
Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The directory extent list does not have to be a continuous list of data
blocks. When GRUB tries to read a non-existant member of the list,
grub_xfs_read_file() will return a block of zero'ed memory. Checking for
a zero'ed magic number is sufficient to skip this non-existant data block.
Prior to commit 07318ee7e (fs/xfs: Fix XFS directory extent parsing)
this was handled as a subtle side effect of reading the (non-existant)
tail data structure. Since the block was zero'ed the computation of the
number of directory entries in the block would return 0 as well.
Fixes: 07318ee7e (fs/xfs: Fix XFS directory extent parsing)
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2254370
Signed-off-by: Jon DeVree <nuxi@vault24.org>
Reviewed-By: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
XFS introduced 64-bit extent counters for inodes via a series of
upstream commits and the feature was marked as stable in v6.5 via
commit 61d7e8274cd8 (xfs: drop EXPERIMENTAL tag for large extent
counts).
Further, xfsprogs release v6.5.0 switched this feature on by default
in mkfs.xfs via commit e5b18d7d1d96 (mkfs: enable large extent counts
by default).
Filesystems formatted with large extent count support, nrext64=1, are
thus currently not recognizable by GRUB, since this is an incompat
feature. Add the required support so that those filesystems and inodes
with large extent counters can be read by GRUB.
Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Andrey Albershteyn <aalbersh@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Marta Lewandowska <mlewando@redhat.com>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
The XFS directory entry parsing code has never been completely correct
for extent based directories. The parser correctly handles the case
where the directory is contained in a single extent, but then mistakenly
assumes the data blocks for the multiple extent case are each identical
to the single extent case. The difference in the format of the data
blocks between the two cases is tiny enough that its gone unnoticed for
a very long time.
A recent change introduced some additional bounds checking into the XFS
parser. Like GRUB's existing parser, it is correct for the single extent
case but incorrect for the multiple extent case. When parsing a directory
with multiple extents, this new bounds checking is sometimes (but not
always) tripped and triggers an "invalid XFS directory entry" error. This
probably would have continued to go unnoticed but the /boot/grub/<arch>
directory is large enough that it often has multiple extents.
The difference between the two cases is that when there are multiple
extents, the data blocks do not contain a trailer nor do they contain
any leaf information. That information is stored in a separate set of
extents dedicated to just the leaf information. These extents come after
the directory entry extents and are not included in the inode size. So
the existing parser already ignores the leaf extents.
The only reason to read the trailer/leaf information at all is so that
the parser can avoid misinterpreting that data as directory entries. So
this updates the parser as follows:
For the single extent case the parser doesn't change much:
1. Read the size of the leaf information from the trailer
2. Set the end pointer for the parser to the start of the leaf
information. (The previous bounds checking set the end pointer to the
start of the trailer, so this is actually a small improvement.)
3. Set the entries variable to the expected number of directory entries.
For the multiple extent case:
1. Set the end pointer to the end of the block.
2. Do not set up the entries variable. Figuring out how many entries are
in each individual block is complex and does not seem worth it when
it appears to be safe to just iterate over the entire block.
The bounds check itself was also dependent upon the faulty XFS parser
because it accidentally used "filename + length - 1". Presumably this
was able to pass the fuzzer because in the old parser there was always
8 bytes of slack space between the tail pointer and the actual end of
the block. Since this is no longer the case the bounds check needs to be
updated to "filename + length + 1" in order to prevent a regression in
the handling of corrupt fliesystems.
Notes:
* When there is only one extent there will only ever be one block. If
more than one block is required then XFS will always switch to holding
leaf information in a separate extent.
* B-tree based directories seems to be parsed properly by the same code
that handles multiple extents. This is unlikely to ever occur within
/boot though because its only used when there are an extremely large
number of directory entries.
Fixes: ef7850c75 (fs/xfs: Fix issues found while fuzzing the XFS filesystem)
Fixes: b2499b29c (Adds support for the XFS filesystem.)
Fixes: https://savannah.gnu.org/bugs/?64376
Signed-off-by: Jon DeVree <nuxi@vault24.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Tested-by: Marta Lewandowska <mlewando@redhat.com>
After parsing of the current entry, the entry pointer is advanced
to the next entry at the end of the "for" loop. In case where the
last entry is at the end of the data boundary, the advanced entry
pointer can point off the data boundary. The subsequent boundary
check for the advanced entry pointer can cause a failure.
The fix is to include the boundary check into the "for" loop
condition.
Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Tested-by: Marta Lewandowska <mlewando@redhat.com>
While performing fuzz testing with XFS filesystem images with ASAN
enabled, several issues were found where the memory accesses are made
beyond the data that is allocated into the struct grub_xfs_data
structure's data field.
The existing structure didn't store the size of the memory allocated into
the buffer in the data field and had no way to check it. To resolve these
issues, the data size is stored to enable checks into the data buffer.
With these checks in place, the fuzzing corpus no longer cause any crashes.
Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Robbie Harwood <rharwood@redhat.com>
Signed-off-by: Marta Lewandowska <mlewando@redhat.com>
Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The commit 8b1e5d193 (fs/xfs: Add bigtime incompat feature support)
introduced the bigtime support by adding some features in v3 inodes.
This change extended grub_xfs_inode struct by 76 bytes but also changed
the computation of XFS_V2_INODE_SIZE and XFS_V3_INODE_SIZE. Prior this
commit, XFS_V2_INODE_SIZE was 100 bytes. After the commit it's 84 bytes
XFS_V2_INODE_SIZE becomes 16 bytes too small.
As a result, the data structures aren't properly aligned and the GRUB
generates "attempt to read or write outside of partition" errors when
trying to read the XFS filesystem:
GNU GRUB version 2.11
....
grub> set debug=efi,gpt,xfs
grub> insmod part_gpt
grub> ls (hd0,gpt1)/
partmap/gpt.c:93: Read a valid GPT header
partmap/gpt.c:115: GPT entry 0: start=4096, length=1953125
fs/xfs.c:931: Reading sb
fs/xfs.c:270: Validating superblock
fs/xfs.c:295: XFS v4 superblock detected
fs/xfs.c:962: Reading root ino 128
fs/xfs.c:515: Reading inode (128) - 64, 0
fs/xfs.c:515: Reading inode (739521961424144223) - 344365866970255880, 3840
error: attempt to read or write outside of partition.
This commit change the XFS_V2_INODE_SIZE computation by subtracting 76
bytes instead of 92 bytes from the actual size of grub_xfs_inode struct.
This 76 bytes value comes from added members:
20 grub_uint8_t unused5
1 grub_uint64_t flags2
48 grub_uint8_t unused6
This patch explicitly splits the v2 and v3 parts of the structure.
The unused4 is still ending of the v2 structures and the v3 starts
at unused5. Thanks to this we will avoid future corruptions of v2
or v3 inodes.
The XFS_V2_INODE_SIZE is returning to its expected size and the
filesystem is back to a readable state:
GNU GRUB version 2.11
....
grub> set debug=efi,gpt,xfs
grub> insmod part_gpt
grub> ls (hd0,gpt1)/
partmap/gpt.c:93: Read a valid GPT header
partmap/gpt.c:115: GPT entry 0: start=4096, length=1953125
fs/xfs.c:931: Reading sb
fs/xfs.c:270: Validating superblock
fs/xfs.c:295: XFS v4 superblock detected
fs/xfs.c:962: Reading root ino 128
fs/xfs.c:515: Reading inode (128) - 64, 0
fs/xfs.c:515: Reading inode (128) - 64, 0
fs/xfs.c:931: Reading sb
fs/xfs.c:270: Validating superblock
fs/xfs.c:295: XFS v4 superblock detected
fs/xfs.c:962: Reading root ino 128
fs/xfs.c:515: Reading inode (128) - 64, 0
fs/xfs.c:515: Reading inode (128) - 64, 0
fs/xfs.c:515: Reading inode (128) - 64, 0
fs/xfs.c:515: Reading inode (131) - 64, 768
efi/ fs/xfs.c:515: Reading inode (3145856) - 1464904, 0
grub2/ fs/xfs.c:515: Reading inode (132) - 64, 1024
grub/ fs/xfs.c:515: Reading inode (139) - 64, 2816
grub>
Fixes: 8b1e5d193 (fs/xfs: Add bigtime incompat feature support)
Signed-off-by: Erwan Velu <e.velu@criteo.com>
Tested-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The XFS now has an incompat feature flag to indicate that a filesystem
needs to be repaired. The Linux kernel refuses to mount the filesystem
that has it set and only the xfs_repair tool is able to clear that flag.
The GRUB doesn't have the concept of mounting filesystems and just
attempts to read the files. But it does some sanity checking before
attempting to read from the filesystem. Among the things which are tested,
is if the super block only has set of incompatible features flags that
are supported by GRUB. If it contains any flags that are not listed as
supported, reading the XFS filesystem fails.
Since the GRUB doesn't attempt to detect if the filesystem is inconsistent
nor replays the journal, the filesystem access is a best effort. For this
reason, ignore if the filesystem needs to be repaired and just print a debug
message. That way, if reading or booting fails later, the user is able to
figure out that the failures can be related to broken XFS filesystem.
Suggested-by: Eric Sandeen <esandeen@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The XFS filesystem supports a bigtime feature to overcome y2038 problem.
This patch makes the GRUB able to support the XFS filesystems with this
feature enabled.
The XFS counter for the bigtime enabled timestamps starts at 0, which
translates to GRUB_INT32_MIN (Dec 31 20:45:52 UTC 1901) in the legacy
timestamps. The conversion to Unix timestamps is made before passing the
value to other GRUB functions.
For this to work properly, GRUB requires an access to flags2 field in the
XFS ondisk inode. So, the grub_xfs_inode structure has been updated to
cover full ondisk inode.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This attempts to fix the places where we do the following where
arithmetic_expr may include unvalidated data:
X = grub_malloc(arithmetic_expr);
It accomplishes this by doing the arithmetic ahead of time using grub_add(),
grub_sub(), grub_mul() and testing for overflow before proceeding.
Among other issues, this fixes:
- allocation of integer overflow in grub_video_bitmap_create()
reported by Chris Coulson,
- allocation of integer overflow in grub_png_decode_image_header()
reported by Chris Coulson,
- allocation of integer overflow in grub_squash_read_symlink()
reported by Chris Coulson,
- allocation of integer overflow in grub_ext2_read_symlink()
reported by Chris Coulson,
- allocation of integer overflow in read_section_as_string()
reported by Chris Coulson.
Fixes: CVE-2020-14309, CVE-2020-14310, CVE-2020-14311
Signed-off-by: Peter Jones <pjones@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The sparse inode metadata format became a mkfs.xfs default in
xfsprogs-4.16.0, and such filesystems are now rejected by grub as
containing an incompatible feature.
In essence, this feature allows xfs to allocate inodes into fragmented
freespace. (Without this feature, if xfs could not allocate contiguous
space for 64 new inodes, inode creation would fail.)
In practice, the disk format change is restricted to the inode btree,
which as far as I can tell is not used by grub. If all you're doing
today is parsing a directory, reading an inode number, and converting
that inode number to a disk location, then ignoring this feature
should be fine, so I've added it to XFS_SB_FEAT_INCOMPAT_SUPPORTED
I did some brief testing of this patch by hacking up the regression
tests to completely fragment freespace on the test xfs filesystem, and
then write a large-ish number of inodes to consume any existing
contiguous 64-inode chunk. This way any files the grub tests add and
traverse would be in such a fragmented inode allocation. Tests passed,
but I'm not sure how to cleanly integrate that into the test harness.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Chris Murphy <lists@colorremedies.com>
XFS V5 stores UUID in metadata and compares them with superblock UUID.
To allow changing of user-visible UUID it stores original value in new
superblock field (meta_uuid) and sets incompatible flag to indicate that
new field must be used to verify metadata. Our driver currently does not
check metadata UUID so simply accept such filesystem.
Reported-By: Marcos Mello <marcosfrm@outlook.com>
Reviewd by Jan Kara <jack@suse.cz>
grub_xfs_iterate_dir did not restore first character after inline
name when match was found. Dependning on XFS format this character
could be inode number and we could return to the same node later in
find_file if processing cycled symlinks.
CID: 86724
Add support for new XFS on disk format. We have to handle optional
filetype fields in directory entries, additional CRC, LSN, UUID entries
in some structures, etc.
Signed-off-by: Jan Kara <jack@suse.cz>
Currently XFS driver converted inode numbers to native endianity only
when using them to compute inode position. Although this works, it is
somewhat confusing. So convert inode numbers when reading them from disk
structures as every other field.
Signed-off-by: Jan Kara <jack@suse.cz>
Directory iteration used wrong position (sizeof wrong structure) for
termination of iteration inside a directory block. Luckily the position
ended up being wrong by just 1 byte and directory entries are larger so
things worked out fine in practice. But fix the problem anyway.
Signed-off-by: Jan Kara <jack@suse.cz>
* grub-core/fs/affs.c (grub_affs_time): New struct.
(grub_affs_file): New field mtime.
(grub_fshelp_node): Changed 'block' and 'parent' to more appropriate
type. Removed 'size'. New field 'di'. All users updated.
(grub_affs_mount): Simplify checsum checking.
(grub_affs_iterate_dir): New helper grub_affs_create_node.
(grub_affs_dir): Handle mtime.
* grub-core/fs/cpio.c (grub_cpio_find_file): Handle mtime.
(grub_cpio_dir): Likewise.
* grub-core/fs/hfs.c (grub_hfs_dirrec): New fields 'ctime' and 'mtime'.
(grub_hfs_filerec): New field mtime.
(grub_hfs_dir): Handle mtime.
(grub_hfs_mtime): New function.
(grub_hfs_fs): Register grub_hfs_mtime.
* grub-core/fs/iso9660.c (grub_iso9660_date2): New struct.
(grub_iso9660_dir): New field mtime.
(grub_fshelp_node): New field dirent.
(iso9660_to_unixtime): New function.
(iso9660_to_unixtime2): Likewise.
(grub_iso9660_read_symlink): Use node->dirent.
(grub_iso9660_iterate_dir): Likewise.
(grub_iso9660_dir): Set mtime.
(grub_iso9660_mtime): New function.
(grub_iso9660_fs): Register grub_iso9660_mtime.
* grub-core/fs/jfs.c (grub_jfs_time): New struct.
(grub_jfs_inode): New fields atime, ctime and mtime.
(grub_jfs_dir): Set mtime.
* grub-core/fs/minix.c (grub_minix_dir): Likewise.
* grub-core/fs/ntfs.c (list_file): Set mtime.
(grub_ntfs_dir): Likewise.
* grub-core/fs/reiserfs.c (grub_fshelp_node): New field 'mtime'.
(grub_reiserfs_iterate_dir): Set mtime.
(grub_reiserfs_dir): Likewise.
* grub-core/fs/sfs.c (grub_sfs_obj): New field mtime.
(grub_fshelp_node): Likewise.
(grub_sfs_iterate_dir): Set mtime.
(grub_sfs_dir): Likewise.
* grub-core/fs/udf.c (grub_udf_dir): Set mtime.
* grub-core/fs/xfs.c (grub_xfs_time): New struct.
(grub_xfs_inode): New fields atime, mtime, ctime.
(grub_xfs_dir): Set mtime.
* include/grub/datetime.h (grub_datetime2unixtime): New function.
* include/grub/hfs.h (grub_hfs_sblock): New fields ctime and mtime.
* include/grub/ntfs.h (grub_fshelp_node): New field mtime.
Support UDF symlinks.
* grub-core/fs/udf.c (grub_udf_iterate_dir): Handle symlinks.
(grub_ufs_read_symlink): New function. All users updated.
Check amiga partmap checksum.
* grub-core/partmap/amiga.c (grub_amiga_rdsk): Pad to 128 bytes.
(grub_amiga_partition): Likewise.
(amiga_partition_map_checksum): New function.
(amiga_partition_map_iterate): Check checksum.
