fs: avoid possible NULL dereference in fs_devread
It is unwise to first dereference a variable
and then to check if it was NULL.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Marek Behun <marek.behun@nic.cz>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/fs/fs_internal.c b/fs/fs_internal.c
index 58b4410..5cdd272 100644
--- a/fs/fs_internal.c
+++ b/fs/fs_internal.c
@@ -15,12 +15,13 @@
lbaint_t sector, int byte_offset, int byte_len, char *buf)
{
unsigned block_len;
- int log2blksz = blk->log2blksz;
+ int log2blksz;
ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (blk ? blk->blksz : 0));
if (blk == NULL) {
printf("** Invalid Block Device Descriptor (NULL)\n");
return 0;
}
+ log2blksz = blk->log2blksz;
/* Check partition boundaries */
if ((sector + ((byte_offset + byte_len - 1) >> log2blksz))