ast@cs.vu.nl (Andy Tanenbaum) (06/28/90)
Thanks to Martin Patzel of Germany for pointing out this truly gross bug. That MINIX ever worked is close to a miracle. Andy Tanenbaum (ast@cs.vu.nl) echo x - open.cdif sed '/^X/s///' > open.cdif << '/' X*** open.c Sat May 5 13:14:25 1990 X--- open.new Wed Jun 27 23:56:54 1990 X*************** X*** 55,61 **** X if (fetch_name(name1, name1_length, M1) != OK) return(err_code); X bits = (mode & I_TYPE) | (mode & ALL_MODES & fp->fp_umask); X size = (unsigned int) name2; X! put_inode(new_node(user_path, bits, (zone_nr) addr), (off_t)size*BLOCK_SIZE); X return(err_code); X } X X--- 55,61 ---- X if (fetch_name(name1, name1_length, M1) != OK) return(err_code); X bits = (mode & I_TYPE) | (mode & ALL_MODES & fp->fp_umask); X size = (unsigned int) name2; X! put_inode(new_node(user_path, bits, (zone_nr) addr, (off_t)size*BLOCK_SIZE)); X return(err_code); X } X /
ghelmer@dsuvax.uucp (Guy Helmer) (06/28/90)
This looks like a fairly important fix. From a casual perusal of the
code, how did a file's length ever get set correctly? Function
new_node in open.c would have been putting junk in the i_size field
of every inode for every new file.
--
Guy Helmer ...!bigtex!loft386!dsuvax!ghelmer
DSU Computing Services ghelmer@dsuvax.uucp, helmer@sdnet.bitnet
Small is beautiful, but looks aren't everything...croes@fwi.uva.nl (Felix A. Croes) (07/01/90)
In article <1990Jun28.153540.2584@dsuvax.uucp> ghelmer@dsuvax.uucp (Guy Helmer) writes: >This looks like a fairly important fix. From a casual perusal of the >code, how did a file's length ever get set correctly? Function >new_node in open.c would have been putting junk in the i_size field >of every inode for every new file. It is not really a miracle, but a coincidence. First, the last argument is put on the stack, intended as an argument for put_inode. Then, the arguments for new_node are evaluated and pushed. So new_node finds the arguments on the stack exactly in the way they should be - only, according to the way it is invoced, it should not know about or make use of the last argument. Put_inode will expect only one argument, and ignore any others. If my assumption is correct, this fix should not result in any change in the minix.img output. -- Felix Croes (croes@fwi.uva.nl)