Re: [patch] isdn: fix a wrapping bug in isdn_ppp_ioctl()
flat view
From: Andreas Schwab <hidden>
Date: 2012-10-10 12:05:06
Also in:
kernel-janitors
Joe Perches [off-list ref] writes:
quoted hunk ↗ jump to hunk
@@ -589,16 +589,15 @@ isdn_ppp_ioctl(int min, struct file *file, unsigned int cmd, unsigned long arg) break; case PPPIOCGCOMPRESSORS: { - unsigned long protos[8] = {0,}; + DECLARE_BITMAP(protos, BITS_PER_LONG * 8) = { 0, }; struct isdn_ppp_compressor *ipc = ipc_head; + while (ipc) { - j = ipc->num / (sizeof(long) * 8); - i = ipc->num % (sizeof(long) * 8); - if (j < 8) - protos[j] |= (0x1 << i); + if (ipc->num < BITS_PER_LONG * 8) + set_bit(ipc->num, protos); ipc = ipc->next; } - if ((r = set_arg(argp, protos, 8 * sizeof(long)))) + if ((r = set_arg(argp, protos, sizeof(protos))))
This changes the bit endianess. Since protos is exported to user space it is an ABI change. Andreas. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different."