On 06/02/2017 09:35 PM, Eric Biggers wrote: > From: Eric Biggers <ebiggers@xxxxxxxxxx> > > gcc 7.1 reports the following warning: > > block/elevator.c: In function ‘elv_register’: > block/elevator.c:898:5: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=] > "%s_io_cq", e->elevator_name); > ^~~~~~~~~~ > block/elevator.c:897:3: note: ‘snprintf’ output between 7 and 22 bytes into a destination of size 21 > snprintf(e->icq_cache_name, sizeof(e->icq_cache_name), > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > "%s_io_cq", e->elevator_name); > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > The bug is that the name of the icq_cache is 6 characters longer than > the elevator name, but only ELV_NAME_MAX + 5 characters were reserved > for it --- so in the case of a maximum-length elevator name, the 'q' > character in "_io_cq" would be truncated by snprintf(). Fix it by > reserving ELV_NAME_MAX + 6 characters instead. Added, thanks. -- Jens Axboe
