Smatch reported a possible buffer overflow in exfat_set_label but it
turns out that this code is unused so just guard the function with
'#ifndef __UBOOT__' as well as exfat_get_label that is also unused and
the helper static find_label.

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>

Andrew Goodbody <andrew.goodbody@linaro.org> says:

Smatch reported issues with variables being dereferenced before NULL
checks and also testing an unsigned variable for being negative.

Link: https://lore.kernel.org/r/20250707-exfat_fix-v1-0-e5783978cd11@linaro.org

In exfat_generic_pread and exfat_generic_pwrite offset is passed in as a
off_t type which is defined as 'unsigned long long' so there is no need
to create the variable uoffset as a uint64_t as this is just a direct
copy of offset. Also remove the impossible test of 'offset < 0' as this
is always false due to offset being unsigned.

This issue found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>

In the functions exfat_pread and exfat_pwrite there is a NULL check for
ctxt.cur_dev but this has already been derefenced twice before this
happens.
Refactor the code a bit to put the NULL check first.

This issue found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>

multi is guaranteed to be NULL in the first two error exit paths so the
attempt to free it is not needed. Remove those calls.

This issue found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>

The assignments to sect and off use the pointer from ctxt.cur_dev but
that has not been NULL checked before this is done. So instead move the
assignments after the NULL check.

This issue found by Smatch

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>
Reviewed-by: Gao Xiang <xiang@kernel.org>

Andrew Goodbody <andrew.goodbody@linaro.org> says:

Smatch reported some issues in the ext4fs code. This includes a
suggestion to use an unwind goto, to not negate a return value and to
ensure that a NULL check happens before the pointer is dereferenced.

Link: https://lore.kernel.org/r/20250704-ext4fs_fix-v1-0-5c6acf4bf839@linaro.org

In the function put_ext4 there is a NULL check for fs->dev_desc but this
has already been derefenced twice before this happens. Refactor the code
a bit to put the NULL check first.

This issue found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>

Ensure that allocated memory is freed on error exit replace the direct
return calls with 'goto fail'.

This issue found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>

In ext4fs_readdir it calls ext4fs_read_file and checks the return value
for non-zero to detect an error. This return value should be returned as
is rather than being negated.

This issue found by Smatch

Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>