mmc: fix signed vs unsigned compare in read check in _spl_load()
Fix signed vs unsigned compare in read check in _spl_load()
Issue: when info->read() returns a negative value because of an error,
the comparison of 'read' (signed) with 'sizeof(*header)'
(unsigned silently converts the negative value into a very
large unsigned value and the check on the error condition
always return false, i.e. the error is not detected
Symptoms: if spl_load_image_fat() is unable to find the file 'uImage',
the SPL phase of the boot process just hangs after displaying
the following line:
Trying to boot from MMC1
Fix: cast 'sizeof(*header)' to int so the compare is now between
signed types
Reference: https://stackoverflow.com/questions/17293749/sizeof-operator-in-if-statement
Signed-off-by: Franco Venturi <fventuri@comcast.net>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
diff --git a/include/spl_load.h b/include/spl_load.h
index 1c2b296..83db381 100644
--- a/include/spl_load.h
+++ b/include/spl_load.h
@@ -22,7 +22,7 @@
read = info->read(info, offset, ALIGN(sizeof(*header),
spl_get_bl_len(info)), header);
- if (read < sizeof(*header))
+ if (read < (int)sizeof(*header))
return -EIO;
if (image_get_magic(header) == FDT_MAGIC) {