dell-laptop: Fix krealloc() misuse in parse_da_table()

If krealloc() returns NULL, it *doesn't* free the original. So any code
of the form 'foo = krealloc(foo, …);' is almost certainly a bug.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index fa3ee6209572..1134119521ac 100644
--- a/drivers/platform/x86/dell-laptop.c
+++ b/drivers/platform/x86/dell-laptop.c
@@ -284,6 +284,7 @@ static void __init parse_da_table(const struct dmi_header *dm)
 {
         /* Final token is a terminator, so we don't want to copy it */
         int tokens = (dm->length-11)/sizeof(struct calling_interface_token)-1;
+        struct calling_interface_token *new_da_tokens;
         struct calling_interface_structure *table =
                 container_of(dm, struct calling_interface_structure, header);
 
@@ -296,12 +297,13 @@ static void __init parse_da_table(const struct dmi_header *dm)
         da_command_address = table->cmdIOAddress;
         da_command_code = table->cmdIOCode;
 
-        da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
-                             sizeof(struct calling_interface_token),
-                             GFP_KERNEL);
+        new_da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
+                                 sizeof(struct calling_interface_token),
+                                 GFP_KERNEL);
 
-        if (!da_tokens)
+        if (!new_da_tokens)
                 return;
+        da_tokens = new_da_tokens;
 
         memcpy(da_tokens+da_num_tokens, table->tokens,
                sizeof(struct calling_interface_token) * tokens);