Urgent printk fix for 5.10

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Merge tag 'printk-for-5.10-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk fix from Petr Mladek:
 "Prevent overflow in the new lockless ringbuffer"

* tag 'printk-for-5.10-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: ringbuffer: Wrong data pointer when appending small string
This commit is contained in:
Linus Torvalds 2020-10-16 12:52:37 -07:00
commit 8119c4332d

View File

@ -1125,7 +1125,10 @@ static char *data_realloc(struct printk_ringbuffer *rb,
/* If the data block does not increase, there is nothing to do. */
if (head_lpos - next_lpos < DATA_SIZE(data_ring)) {
blk = to_block(data_ring, blk_lpos->begin);
if (wrapped)
blk = to_block(data_ring, 0);
else
blk = to_block(data_ring, blk_lpos->begin);
return &blk->data[0];
}