From 24f48416dfe1d827dcf759d6cd0e7a8e5c67e321 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Sun, 19 Nov 2017 23:49:21 +0100 Subject: [PATCH] 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 Reviewed-by: Marek Behun Reviewed-by: Bin Meng --- fs/fs_internal.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/fs_internal.c b/fs/fs_internal.c index 58b441030c..5cdd272c9d 100644 --- a/fs/fs_internal.c +++ b/fs/fs_internal.c @@ -15,12 +15,13 @@ int fs_devread(struct blk_desc *blk, disk_partition_t *partition, 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)) -- 2.39.5