diff options
Diffstat (limited to 'kernel/printk/printk_ringbuffer.c')
| -rw-r--r-- | kernel/printk/printk_ringbuffer.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/kernel/printk/printk_ringbuffer.c b/kernel/printk/printk_ringbuffer.c index 13b94b92342e..2493348a1631 100644 --- a/kernel/printk/printk_ringbuffer.c +++ b/kernel/printk/printk_ringbuffer.c @@ -202,7 +202,8 @@ * // specify additional 5 bytes text space to extend * prb_rec_init_wr(&r, 5); * - * if (prb_reserve_in_last(&e, &test_rb, &r, printk_caller_id())) { + * // try to extend, but only if it does not exceed 32 bytes + * if (prb_reserve_in_last(&e, &test_rb, &r, printk_caller_id()), 32) { * snprintf(&r.text_buf[r.info->text_len], * r.text_buf_size - r.info->text_len, "hello"); * @@ -1309,6 +1310,7 @@ static struct prb_desc *desc_reopen_last(struct prb_desc_ring *desc_ring, * @rb: The ringbuffer to re-reserve and extend data in. * @r: The record structure to allocate buffers for. * @caller_id: The caller ID of the caller (reserving writer). + * @max_size: Fail if the extended size would be greater than this. * * This is the public function available to writers to re-reserve and extend * data. @@ -1343,7 +1345,7 @@ static struct prb_desc *desc_reopen_last(struct prb_desc_ring *desc_ring, * @r->info->text_len after concatenating. */ bool prb_reserve_in_last(struct prb_reserved_entry *e, struct printk_ringbuffer *rb, - struct printk_record *r, u32 caller_id) + struct printk_record *r, u32 caller_id, unsigned int max_size) { struct prb_desc_ring *desc_ring = &rb->desc_ring; struct printk_info *info; @@ -1389,6 +1391,9 @@ bool prb_reserve_in_last(struct prb_reserved_entry *e, struct printk_ringbuffer if (!data_check_size(&rb->text_data_ring, r->text_buf_size)) goto fail; + if (r->text_buf_size > max_size) + goto fail; + r->text_buf = data_alloc(rb, &rb->text_data_ring, r->text_buf_size, &d->text_blk_lpos, id); } else { @@ -1410,6 +1415,9 @@ bool prb_reserve_in_last(struct prb_reserved_entry *e, struct printk_ringbuffer if (!data_check_size(&rb->text_data_ring, r->text_buf_size)) goto fail; + if (r->text_buf_size > max_size) + goto fail; + r->text_buf = data_realloc(rb, &rb->text_data_ring, r->text_buf_size, &d->text_blk_lpos, id); } |