Signed-off-by: Aneesh V <aneesh@ti.com>

Fat directory handling didn't check reaching the end of the root directory. It
relied on a stop condition based on a directory entry with a name starting with
a '\0' character. This check in itself is wrong ('\0' indicates free entry, not
end_of_directory) but outside the scope of this fix. For FAT32, the end of the
rootdir is reached when the end of the cluster chain is reached. The code didn't
check this condition and started to read an incorrect cluster. This caused a
subsequent read request of a sector outside the range of the usb stick in
use. On its turn, the usb stick protested with a stall handshake.

Both FAT32 and non-FAT32 (FAT16/FAT12) end or rootdir checks have been put in.

Signed-off-by: Erik Hansen <erik@makarta.com>

Before this commit, weak symbols were not overridden by non-weak symbols
found in archive libraries when linking with recent versions of
binutils.  As stated in the System V ABI, "the link editor does not
extract archive members to resolve undefined weak symbols".

This commit changes all Makefiles to use partial linking (ld -r) instead
of creating library archives, which forces all symbols to participate in
linking, allowing non-weak symbols to override weak symbols as intended.
This approach is also used by Linux, from which the gmake function
cmd_link_o_target (defined in config.mk and used in all Makefiles) is
inspired.

The name of each former library archive is preserved except for
extensions which change from ".a" to ".o".  This commit updates
references accordingly where needed, in particular in some linker
scripts.

This commit reveals board configurations that exclude some features but
include source files that depend these disabled features in the build,
resulting in undefined symbols.  Known such cases include:
- disabling CMD_NET but not CMD_NFS;
- enabling CONFIG_OF_LIBFDT but not CONFIG_QE.

Signed-off-by: Sebastien Carlier <sebastien.carlier@gmail.com>

Last commit 3831530dcb7b71329c272ccd6181f8038b6a6dd0a was intended
"explicitly specify FAT12/16 root directory parsing buffer size, instead
of relying on cluster size". Howver, the underlying function requires
the size of the buffer in blocks, not in bytes, and instead of passing
a double sector size a request for 1024 blocks is sent. This generates
a buffer overflow with overwriting of other structure (in the case seen,
USB structures were overwritten).

Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Mikhail Zolotaryov <lebon@lebon.org.ua>

The U-Boot code has the following bugs related to the processing of Long File
Name (LFN) entries scattered across several clusters/sectors :

1) get_vfatname() function is designed to gather scattered LFN entries by
cluster chain processing - that doesn't work for FAT12/16 root directory.
In other words, the function expects the following input data:
 1.1) FAT32 directory (which is cluster chain based);
        OR
 1.2) FAT12/16 non-root directory (which is also cluster chain based);
        OR
 1.3) FAT12/16 root directory (allocated as contiguous sectors area), but
 all necessary information MUST be within the input buffer of filesystem cluster
 size (thus cluster-chain jump is never initiated).

In order to accomplish the last condition, root directory parsing code in
do_fat_read() uses the following trick: read-out cluster-size block, process
only first sector (512 bytes), then shift 512 forward, read-out cluster-size
block and so on. This works great unless cluster size is equal to 512 bytes
(in a case you have a small partition), or long file name entries are scattered
across three sectors, see 4) for details.

2) Despite of the fact that get_vfatname() supports FAT32 root directory
browsing, do_fat_read() function doesn't send current cluster number correctly,
so root directory look-up doesn't work correctly.

3) get_vfatname() doesn't gather scattered entries correctly also is the case
when all LFN entries are located at the end of the source cluster, but real
directory entry (which must be returned) is at the only beginning of the
next one. No error detected, the resulting directory entry returned contains
a semi-random information (wrong size, wrong start cluster number and so on)
i.e. the entry is not accessible.

4) LFN (VFAT) allows up to 20 entries (slots) each containing 26 bytes (13
UTF-16 code units) to represent a single long file name i.e. up to 520 bytes.
U-Boot allocates 256 bytes buffer instead, i.e. 10 or more LFN slots record
may cause buffer overflow / memory corruption.
Also, it's worth to mention that 20+1 slots occupy 672 bytes space which may
take more than one cluster of 512 bytes (medium-size FAT32 or small FAT16
partition) - get_vfatname() function doesn't support such case as well.

The patch attached fixes these problems in the following way:
- keep using 256 bytes buffer for a long file name, but safely prevent a
possible buffer overflow (skip LFN processing, if it contains 10 or more
slots).

- explicitly specify FAT12/16 root directory parsing buffer size, instead
of relying on cluster size. The value used is a double sector size (to store
current sector and the next one). This fixes the first problem and increases
performance on big FAT12/16 partitions;

- send current cluster number (FAT32) to get_vfatname() during root
directory processing;

- use LFN counter to seek the real directory entry in get_vfatname() - fixes the
third problem;

- skip deleted entries in the root directory (to prevent bogus buffer
overflow detection and LFN counter steps).

Note: it's not advised to split up the patch, because a separate part may
operate incorrectly.

Signed-off-by: Mikhail Zolotaryov <lebon@lebon.org.ua>

- reformat
- throw out macros like FAT_DPRINT and FAT_DPRINT
- remove dead code

Signed-off-by: Wolfgang Denk <wd@denx.de>

On FAT32, instead of fetching the cluster numbers from the FAT, the
code assumed (incorrectly) that the clusters for the root directory
were allocated contiguously. In the result, only the first cluster
could be accessed. At the typical cluster size of 8 sectors this
caused all accesses to files after the first 128 entries to fail -
"fatls" would terminate after 128 files (usually displaying a bogus
file name, occasionally even crashing the system), and "fatload"
would fail to find any files that were not in the first directory
cluster.

Signed-off-by: Wolfgang Denk <wd@denx.de>

"Superfloppy" format (in U-Boot called PBR) did not work for FAT32 as
the file system type string is at a different location. Add support
for FAT32.

Signed-off-by: Wolfgang Denk <wd@denx.de>

The nios-32 arch is obsolete and broken. So it is removed.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>

The static function compare_sign is only used to compare the fs_type string
and does not do anything more than what strncmp does.

The addition of the trailing '\0' to fs_type, while legal, is not needed
because the it is never printed out and strncmp does not depend on NULL
terminated strings.

Signed-off-by: Tom Rix <Tom.Rix@windriver.com>