On Sat, 30 Jul 2016 11:51:09 +0800 zhongjiang <[email protected]> wrote:
> From: zhong jiang <[email protected]> > > when compile the kenrel code, I happens to the following warn. > fs/reiserfs/ibalance.c:1156:2: warning: ___new_insert_key___ may be used > uninitialized in this function. > memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE); > > The patch fix it by check the new_insert_ptr. if new_insert_ptr is not > NULL, we ensure that new_insert_key is assigned. therefore, memcpy will > saftly exec the operatetion. > > --- a/fs/reiserfs/ibalance.c > +++ b/fs/reiserfs/ibalance.c > @@ -1153,8 +1153,10 @@ int balance_internal(struct tree_balance *tb, > insert_ptr); > } > > - memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE); > - insert_ptr[0] = new_insert_ptr; > + if (new_insert_ptr) { > + memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE); > + insert_ptr[0] = new_insert_ptr; > + } > > return order; Jeff has aleady fixed this with an equivalent patch. It's in -mm at present. From: Jeff Mahoney <[email protected]> Subject: reiserfs: fix "new_insert_key may be used uninitialized ..." new_insert_key only makes any sense when it's associated with a new_insert_ptr, which is initialized to NULL and changed to a buffer_head when we also initialize new_insert_key. We can key off of that to avoid the uninitialized warning. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Jeff Mahoney <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Jan Kara <[email protected]> Cc: Linus Torvalds <[email protected]> Signed-off-by: Andrew Morton <[email protected]> --- fs/reiserfs/ibalance.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff -puN fs/reiserfs/ibalance.c~reiserfs-fix-new_insert_key-may-be-used-uninitialized fs/reiserfs/ibalance.c --- a/fs/reiserfs/ibalance.c~reiserfs-fix-new_insert_key-may-be-used-uninitialized +++ a/fs/reiserfs/ibalance.c @@ -1153,8 +1153,9 @@ int balance_internal(struct tree_balance insert_ptr); } - memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE); insert_ptr[0] = new_insert_ptr; + if (new_insert_ptr) + memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE); return order; } _
