/* Key to pathname encoder * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public Licence * as published by the Free Software Foundation; either version * 2 of the Licence, or (at your option) any later version. */ #include #include "internal.h" static const char cachefiles_charmap[64] = "0123456789" /* 0 - 9 */ "abcdefghijklmnopqrstuvwxyz" /* 10 - 35 */ "ABCDEFGHIJKLMNOPQRSTUVWXYZ" /* 36 - 61 */ "_-" /* 62 - 63 */ ; static const char cachefiles_filecharmap[256] = { /* we skip space and tab and control chars */ [33 ... 46] = 1, /* '!' -> '.' */ /* we skip '/' as it's significant to pathwalk */ [48 ... 127] = 1, /* '0' -> '~' */ }; /* * turn the raw key into something cooked * - the raw key should include the length in the two bytes at the front * - the key may be up to 514 bytes in length (including the length word) * - "base64" encode the strange keys, mapping 3 bytes of raw to four of * cooked * - need to cut the cooked key into 252 char lengths (189 raw bytes) */ char *cachefiles_cook_key(const u8 *raw, int keylen, uint8_t type) { unsigned char csum, ch; unsigned int acc; char *key; int loop, len, max, seg, mark, print; _enter(",%d", keylen); BUG_ON(keylen < 2 || keylen > 514); csum = raw[0] + raw[1]; print = 1; for (loop = 2; loop < keylen; loop++) { ch = raw[loop]; csum += ch; print &= cachefiles_filecharmap[ch]; } if (print) { /* if the path is usable ASCII, then we render it directly */ max = keylen - 2; max += 2; /* two base64'd length chars on the front */ max += 5; /* @checksum/M */ max += 3 * 2; /* maximum number of segment dividers (".../M") * is ((514 + 251) / 252) = 3 */ max += 1; /* NUL on end */ } else { /* calculate the maximum length of the cooked key */ keylen = (keylen + 2) / 3; max = keylen * 4; max += 5; /* @checksum/M */ max += 3 * 2; /* maximum number of segment dividers (".../M") * is ((514 + 188) / 189) = 3 */ max += 1; /* NUL on end */ } max += 1; /* 2nd NUL on end */ _debug("max: %d", max); key = kmalloc(max, cachefiles_gfp); if (!key) return NULL; len = 0; /* build the cooked key */ sprintf(key, "@%02x%c+", (unsigned) csum, 0); len = 5; mark = len - 1; if (print) { acc = *(uint16_t *) raw; raw += 2; key[len + 1] = cachefiles_charmap[acc & 63]; acc >>= 6; key[len] = cachefiles_charmap[acc & 63]; len += 2; seg = 250; for (loop = keylen; loop > 0; loop--) { if (seg <= 0) { key[len++] = '\0'; mark = len; key[len++] = '+'; seg = 252; } key[len++] = *raw++; ASSERT(len < max); } switch (type) { case FSCACHE_COOKIE_TYPE_INDEX: type = 'I'; break; case FSCACHE_COOKIE_TYPE_DATAFILE: type = 'D'; break; default: type = 'S'; break; } } else { seg = 252; for (loop = keylen; loop > 0; loop--) { if (seg <= 0) { key[len++] = '\0'; mark = len; key[len++] = '+'; seg = 252; } acc = *raw++; acc |= *raw++ << 8; acc |= *raw++ << 16; _debug("acc: %06x", acc); key[len++] = cachefiles_charmap[acc & 63]; acc >>= 6; key[len++] = cachefiles_charmap[acc & 63]; acc >>= 6; key[len++] = cachefiles_charmap[acc & 63]; acc >>= 6; key[len++] = cachefiles_charmap[acc & 63]; ASSERT(len < max); } switch (type) { case FSCACHE_COOKIE_TYPE_INDEX: type = 'J'; break; case FSCACHE_COOKIE_TYPE_DATAFILE: type = 'E'; break; default: type = 'T'; break; } } key[mark] = type; key[len++] = 0; key[len] = 0; _leave(" = %p %d", key, len); return key; } >space:mode:
authorBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
committerBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
commit030305d69fc6963c16003f50d7e8d74b02d0a143 (patch)
tree363a4e34d199178769b7e7eeb26ea2620a55847b /net/rxrpc/af_rxrpc.c
parent4d191b1b63c209e37bf27938ef365244d3c41084 (diff)
PCI/ASPM: Handle PCI-to-PCIe bridges as roots of PCIe hierarchies
In a struct pcie_link_state, link->root points to the pcie_link_state of the root of the PCIe hierarchy. For the topmost link, this points to itself (link->root = link). For others, we copy the pointer from the parent (link->root = link->parent->root). Previously we recognized that Root Ports originated PCIe hierarchies, but we treated PCI/PCI-X to PCIe Bridges as being in the middle of the hierarchy, and when we tried to copy the pointer from link->parent->root, there was no parent, and we dereferenced a NULL pointer: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffff9e424350>] pcie_aspm_init_link_state+0x170/0x820 Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just like Root Ports do, so link->root for these devices should also point to itself. Fixes: 51ebfc92b72b ("PCI: Enumerate switches below PCI-to-PCIe bridges") Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411 Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181 Tested-by: lists@ssl-mail.com Tested-by: Jayachandran C. <jnair@caviumnetworks.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org # v4.2+
Diffstat (limited to 'net/rxrpc/af_rxrpc.c')