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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /scripts/gcc-plugins/randomize_layout_plugin.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to '')
-rw-r--r-- | scripts/gcc-plugins/randomize_layout_plugin.c | 907 |
1 files changed, 907 insertions, 0 deletions
diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c new file mode 100644 index 000000000..951b74ba1 --- /dev/null +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -0,0 +1,907 @@ +/* + * Copyright 2014-2016 by Open Source Security, Inc., Brad Spengler <spender@grsecurity.net> + * and PaX Team <pageexec@freemail.hu> + * Licensed under the GPL v2 + * + * Note: the choice of the license means that the compilation process is + * NOT 'eligible' as defined by gcc's library exception to the GPL v3, + * but for the kernel it doesn't matter since it doesn't link against + * any of the gcc libraries + * + * Usage: + * $ # for 4.5/4.6/C based 4.7 + * $ gcc -I`gcc -print-file-name=plugin`/include -I`gcc -print-file-name=plugin`/include/c-family -fPIC -shared -O2 -o randomize_layout_plugin.so randomize_layout_plugin.c + * $ # for C++ based 4.7/4.8+ + * $ g++ -I`g++ -print-file-name=plugin`/include -I`g++ -print-file-name=plugin`/include/c-family -fPIC -shared -O2 -o randomize_layout_plugin.so randomize_layout_plugin.c + * $ gcc -fplugin=./randomize_layout_plugin.so test.c -O2 + */ + +#include "gcc-common.h" +#include "randomize_layout_seed.h" + +#if BUILDING_GCC_MAJOR < 4 || (BUILDING_GCC_MAJOR == 4 && BUILDING_GCC_MINOR < 7) +#error "The RANDSTRUCT plugin requires GCC 4.7 or newer." +#endif + +#define ORIG_TYPE_NAME(node) \ + (TYPE_NAME(TYPE_MAIN_VARIANT(node)) != NULL_TREE ? ((const unsigned char *)IDENTIFIER_POINTER(TYPE_NAME(TYPE_MAIN_VARIANT(node)))) : (const unsigned char *)"anonymous") + +#define INFORM(loc, msg, ...) inform(loc, "randstruct: " msg, ##__VA_ARGS__) +#define MISMATCH(loc, how, ...) INFORM(loc, "casting between randomized structure pointer types (" how "): %qT and %qT\n", __VA_ARGS__) + +__visible int plugin_is_GPL_compatible; + +static int performance_mode; + +static struct plugin_info randomize_layout_plugin_info = { + .version = PLUGIN_VERSION, + .help = "disable\t\t\tdo not activate plugin\n" + "performance-mode\tenable cacheline-aware layout randomization\n" +}; + +/* from old Linux dcache.h */ +static inline unsigned long +partial_name_hash(unsigned long c, unsigned long prevhash) +{ + return (prevhash + (c << 4) + (c >> 4)) * 11; +} +static inline unsigned int +name_hash(const unsigned char *name) +{ + unsigned long hash = 0; + unsigned int len = strlen((const char *)name); + while (len--) + hash = partial_name_hash(*name++, hash); + return (unsigned int)hash; +} + +static tree handle_randomize_layout_attr(tree *node, tree name, tree args, int flags, bool *no_add_attrs) +{ + tree type; + + *no_add_attrs = true; + if (TREE_CODE(*node) == FUNCTION_DECL) { + error("%qE attribute does not apply to functions (%qF)", name, *node); + return NULL_TREE; + } + + if (TREE_CODE(*node) == PARM_DECL) { + error("%qE attribute does not apply to function parameters (%qD)", name, *node); + return NULL_TREE; + } + + if (TREE_CODE(*node) == VAR_DECL) { + error("%qE attribute does not apply to variables (%qD)", name, *node); + return NULL_TREE; + } + + if (TYPE_P(*node)) { + type = *node; + } else { + gcc_assert(TREE_CODE(*node) == TYPE_DECL); + type = TREE_TYPE(*node); + } + + if (TREE_CODE(type) != RECORD_TYPE) { + error("%qE attribute used on %qT applies to struct types only", name, type); + return NULL_TREE; + } + + if (lookup_attribute(IDENTIFIER_POINTER(name), TYPE_ATTRIBUTES(type))) { + error("%qE attribute is already applied to the type %qT", name, type); + return NULL_TREE; + } + + *no_add_attrs = false; + + return NULL_TREE; +} + +/* set on complete types that we don't need to inspect further at all */ +static tree handle_randomize_considered_attr(tree *node, tree name, tree args, int flags, bool *no_add_attrs) +{ + *no_add_attrs = false; + return NULL_TREE; +} + +/* + * set on types that we've performed a shuffle on, to prevent re-shuffling + * this does not preclude us from inspecting its fields for potential shuffles + */ +static tree handle_randomize_performed_attr(tree *node, tree name, tree args, int flags, bool *no_add_attrs) +{ + *no_add_attrs = false; + return NULL_TREE; +} + +/* + * 64bit variant of Bob Jenkins' public domain PRNG + * 256 bits of internal state + */ + +typedef unsigned long long u64; + +typedef struct ranctx { u64 a; u64 b; u64 c; u64 d; } ranctx; + +#define rot(x,k) (((x)<<(k))|((x)>>(64-(k)))) +static u64 ranval(ranctx *x) { + u64 e = x->a - rot(x->b, 7); + x->a = x->b ^ rot(x->c, 13); + x->b = x->c + rot(x->d, 37); + x->c = x->d + e; + x->d = e + x->a; + return x->d; +} + +static void raninit(ranctx *x, u64 *seed) { + int i; + + x->a = seed[0]; + x->b = seed[1]; + x->c = seed[2]; + x->d = seed[3]; + + for (i=0; i < 30; ++i) + (void)ranval(x); +} + +static u64 shuffle_seed[4]; + +struct partition_group { + tree tree_start; + unsigned long start; + unsigned long length; +}; + +static void partition_struct(tree *fields, unsigned long length, struct partition_group *size_groups, unsigned long *num_groups) +{ + unsigned long i; + unsigned long accum_size = 0; + unsigned long accum_length = 0; + unsigned long group_idx = 0; + + gcc_assert(length < INT_MAX); + + memset(size_groups, 0, sizeof(struct partition_group) * length); + + for (i = 0; i < length; i++) { + if (size_groups[group_idx].tree_start == NULL_TREE) { + size_groups[group_idx].tree_start = fields[i]; + size_groups[group_idx].start = i; + accum_length = 0; + accum_size = 0; + } + accum_size += (unsigned long)int_size_in_bytes(TREE_TYPE(fields[i])); + accum_length++; + if (accum_size >= 64) { + size_groups[group_idx].length = accum_length; + accum_length = 0; + group_idx++; + } + } + + if (size_groups[group_idx].tree_start != NULL_TREE && + !size_groups[group_idx].length) { + size_groups[group_idx].length = accum_length; + group_idx++; + } + + *num_groups = group_idx; +} + +static void performance_shuffle(tree *newtree, unsigned long length, ranctx *prng_state) +{ + unsigned long i, x; + struct partition_group size_group[length]; + unsigned long num_groups = 0; + unsigned long randnum; + + partition_struct(newtree, length, (struct partition_group *)&size_group, &num_groups); + for (i = num_groups - 1; i > 0; i--) { + struct partition_group tmp; + randnum = ranval(prng_state) % (i + 1); + tmp = size_group[i]; + size_group[i] = size_group[randnum]; + size_group[randnum] = tmp; + } + + for (x = 0; x < num_groups; x++) { + for (i = size_group[x].start + size_group[x].length - 1; i > size_group[x].start; i--) { + tree tmp; + if (DECL_BIT_FIELD_TYPE(newtree[i])) + continue; + randnum = ranval(prng_state) % (i + 1); + // we could handle this case differently if desired + if (DECL_BIT_FIELD_TYPE(newtree[randnum])) + continue; + tmp = newtree[i]; + newtree[i] = newtree[randnum]; + newtree[randnum] = tmp; + } + } +} + +static void full_shuffle(tree *newtree, unsigned long length, ranctx *prng_state) +{ + unsigned long i, randnum; + + for (i = length - 1; i > 0; i--) { + tree tmp; + randnum = ranval(prng_state) % (i + 1); + tmp = newtree[i]; + newtree[i] = newtree[randnum]; + newtree[randnum] = tmp; + } +} + +/* modern in-place Fisher-Yates shuffle */ +static void shuffle(const_tree type, tree *newtree, unsigned long length) +{ + unsigned long i; + u64 seed[4]; + ranctx prng_state; + const unsigned char *structname; + + if (length == 0) + return; + + gcc_assert(TREE_CODE(type) == RECORD_TYPE); + + structname = ORIG_TYPE_NAME(type); + +#ifdef __DEBUG_PLUGIN + fprintf(stderr, "Shuffling struct %s %p\n", (const char *)structname, type); +#ifdef __DEBUG_VERBOSE + debug_tree((tree)type); +#endif +#endif + + for (i = 0; i < 4; i++) { + seed[i] = shuffle_seed[i]; + seed[i] ^= name_hash(structname); + } + + raninit(&prng_state, (u64 *)&seed); + + if (performance_mode) + performance_shuffle(newtree, length, &prng_state); + else + full_shuffle(newtree, length, &prng_state); +} + +static bool is_flexible_array(const_tree field) +{ + const_tree fieldtype; + const_tree typesize; + const_tree elemtype; + const_tree elemsize; + + fieldtype = TREE_TYPE(field); + typesize = TYPE_SIZE(fieldtype); + + if (TREE_CODE(fieldtype) != ARRAY_TYPE) + return false; + + elemtype = TREE_TYPE(fieldtype); + elemsize = TYPE_SIZE(elemtype); + + /* size of type is represented in bits */ + + if (typesize == NULL_TREE && TYPE_DOMAIN(fieldtype) != NULL_TREE && + TYPE_MAX_VALUE(TYPE_DOMAIN(fieldtype)) == NULL_TREE) + return true; + + if (typesize != NULL_TREE && + (TREE_CONSTANT(typesize) && (!tree_to_uhwi(typesize) || + tree_to_uhwi(typesize) == tree_to_uhwi(elemsize)))) + return true; + + return false; +} + +static int relayout_struct(tree type) +{ + unsigned long num_fields = (unsigned long)list_length(TYPE_FIELDS(type)); + unsigned long shuffle_length = num_fields; + tree field; + tree newtree[num_fields]; + unsigned long i; + tree list; + tree variant; + tree main_variant; + expanded_location xloc; + bool has_flexarray = false; + + if (TYPE_FIELDS(type) == NULL_TREE) + return 0; + + if (num_fields < 2) + return 0; + + gcc_assert(TREE_CODE(type) == RECORD_TYPE); + + gcc_assert(num_fields < INT_MAX); + + if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(type)) || + lookup_attribute("no_randomize_layout", TYPE_ATTRIBUTES(TYPE_MAIN_VARIANT(type)))) + return 0; + + /* Workaround for 3rd-party VirtualBox source that we can't modify ourselves */ + if (!strcmp((const char *)ORIG_TYPE_NAME(type), "INTNETTRUNKFACTORY") || + !strcmp((const char *)ORIG_TYPE_NAME(type), "RAWPCIFACTORY")) + return 0; + + /* throw out any structs in uapi */ + xloc = expand_location(DECL_SOURCE_LOCATION(TYPE_FIELDS(type))); + + if (strstr(xloc.file, "/uapi/")) + error(G_("attempted to randomize userland API struct %s"), ORIG_TYPE_NAME(type)); + + for (field = TYPE_FIELDS(type), i = 0; field; field = TREE_CHAIN(field), i++) { + gcc_assert(TREE_CODE(field) == FIELD_DECL); + newtree[i] = field; + } + + /* + * enforce that we don't randomize the layout of the last + * element of a struct if it's a 0 or 1-length array + * or a proper flexible array + */ + if (is_flexible_array(newtree[num_fields - 1])) { + has_flexarray = true; + shuffle_length--; + } + + shuffle(type, (tree *)newtree, shuffle_length); + + /* + * set up a bogus anonymous struct field designed to error out on unnamed struct initializers + * as gcc provides no other way to detect such code + */ + list = make_node(FIELD_DECL); + TREE_CHAIN(list) = newtree[0]; + TREE_TYPE(list) = void_type_node; + DECL_SIZE(list) = bitsize_zero_node; + DECL_NONADDRESSABLE_P(list) = 1; + DECL_FIELD_BIT_OFFSET(list) = bitsize_zero_node; + DECL_SIZE_UNIT(list) = size_zero_node; + DECL_FIELD_OFFSET(list) = size_zero_node; + DECL_CONTEXT(list) = type; + // to satisfy the constify plugin + TREE_READONLY(list) = 1; + + for (i = 0; i < num_fields - 1; i++) + TREE_CHAIN(newtree[i]) = newtree[i+1]; + TREE_CHAIN(newtree[num_fields - 1]) = NULL_TREE; + + main_variant = TYPE_MAIN_VARIANT(type); + for (variant = main_variant; variant; variant = TYPE_NEXT_VARIANT(variant)) { + TYPE_FIELDS(variant) = list; + TYPE_ATTRIBUTES(variant) = copy_list(TYPE_ATTRIBUTES(variant)); + TYPE_ATTRIBUTES(variant) = tree_cons(get_identifier("randomize_performed"), NULL_TREE, TYPE_ATTRIBUTES(variant)); + TYPE_ATTRIBUTES(variant) = tree_cons(get_identifier("designated_init"), NULL_TREE, TYPE_ATTRIBUTES(variant)); + if (has_flexarray) + TYPE_ATTRIBUTES(type) = tree_cons(get_identifier("has_flexarray"), NULL_TREE, TYPE_ATTRIBUTES(type)); + } + + /* + * force a re-layout of the main variant + * the TYPE_SIZE for all variants will be recomputed + * by finalize_type_size() + */ + TYPE_SIZE(main_variant) = NULL_TREE; + layout_type(main_variant); + gcc_assert(TYPE_SIZE(main_variant) != NULL_TREE); + + return 1; +} + +/* from constify plugin */ +static const_tree get_field_type(const_tree field) +{ + return strip_array_types(TREE_TYPE(field)); +} + +/* from constify plugin */ +static bool is_fptr(const_tree fieldtype) +{ + if (TREE_CODE(fieldtype) != POINTER_TYPE) + return false; + + return TREE_CODE(TREE_TYPE(fieldtype)) == FUNCTION_TYPE; +} + +/* derived from constify plugin */ +static int is_pure_ops_struct(const_tree node) +{ + const_tree field; + + gcc_assert(TREE_CODE(node) == RECORD_TYPE || TREE_CODE(node) == UNION_TYPE); + + for (field = TYPE_FIELDS(node); field; field = TREE_CHAIN(field)) { + const_tree fieldtype = get_field_type(field); + enum tree_code code = TREE_CODE(fieldtype); + + if (node == fieldtype) + continue; + + if (code == RECORD_TYPE || code == UNION_TYPE) { + if (!is_pure_ops_struct(fieldtype)) + return 0; + continue; + } + + if (!is_fptr(fieldtype)) + return 0; + } + + return 1; +} + +static void randomize_type(tree type) +{ + tree variant; + + gcc_assert(TREE_CODE(type) == RECORD_TYPE); + + if (lookup_attribute("randomize_considered", TYPE_ATTRIBUTES(type))) + return; + + if (lookup_attribute("randomize_layout", TYPE_ATTRIBUTES(TYPE_MAIN_VARIANT(type))) || is_pure_ops_struct(type)) + relayout_struct(type); + + for (variant = TYPE_MAIN_VARIANT(type); variant; variant = TYPE_NEXT_VARIANT(variant)) { + TYPE_ATTRIBUTES(type) = copy_list(TYPE_ATTRIBUTES(type)); + TYPE_ATTRIBUTES(type) = tree_cons(get_identifier("randomize_considered"), NULL_TREE, TYPE_ATTRIBUTES(type)); + } +#ifdef __DEBUG_PLUGIN + fprintf(stderr, "Marking randomize_considered on struct %s\n", ORIG_TYPE_NAME(type)); +#ifdef __DEBUG_VERBOSE + debug_tree(type); +#endif +#endif +} + +static void update_decl_size(tree decl) +{ + tree lastval, lastidx, field, init, type, flexsize; + unsigned HOST_WIDE_INT len; + + type = TREE_TYPE(decl); + + if (!lookup_attribute("has_flexarray", TYPE_ATTRIBUTES(type))) + return; + + init = DECL_INITIAL(decl); + if (init == NULL_TREE || init == error_mark_node) + return; + + if (TREE_CODE(init) != CONSTRUCTOR) + return; + + len = CONSTRUCTOR_NELTS(init); + if (!len) + return; + + lastval = CONSTRUCTOR_ELT(init, CONSTRUCTOR_NELTS(init) - 1)->value; + lastidx = CONSTRUCTOR_ELT(init, CONSTRUCTOR_NELTS(init) - 1)->index; + + for (field = TYPE_FIELDS(TREE_TYPE(decl)); TREE_CHAIN(field); field = TREE_CHAIN(field)) + ; + + if (lastidx != field) + return; + + if (TREE_CODE(lastval) != STRING_CST) { + error("Only string constants are supported as initializers " + "for randomized structures with flexible arrays"); + return; + } + + flexsize = bitsize_int(TREE_STRING_LENGTH(lastval) * + tree_to_uhwi(TYPE_SIZE(TREE_TYPE(TREE_TYPE(lastval))))); + + DECL_SIZE(decl) = size_binop(PLUS_EXPR, TYPE_SIZE(type), flexsize); + + return; +} + + +static void randomize_layout_finish_decl(void *event_data, void *data) +{ + tree decl = (tree)event_data; + tree type; + + if (decl == NULL_TREE || decl == error_mark_node) + return; + + type = TREE_TYPE(decl); + + if (TREE_CODE(decl) != VAR_DECL) + return; + + if (TREE_CODE(type) != RECORD_TYPE && TREE_CODE(type) != UNION_TYPE) + return; + + if (!lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(type))) + return; + + DECL_SIZE(decl) = 0; + DECL_SIZE_UNIT(decl) = 0; + SET_DECL_ALIGN(decl, 0); + SET_DECL_MODE (decl, VOIDmode); + SET_DECL_RTL(decl, 0); + update_decl_size(decl); + layout_decl(decl, 0); +} + +static void finish_type(void *event_data, void *data) +{ + tree type = (tree)event_data; + + if (type == NULL_TREE || type == error_mark_node) + return; + + if (TREE_CODE(type) != RECORD_TYPE) + return; + + if (TYPE_FIELDS(type) == NULL_TREE) + return; + + if (lookup_attribute("randomize_considered", TYPE_ATTRIBUTES(type))) + return; + +#ifdef __DEBUG_PLUGIN + fprintf(stderr, "Calling randomize_type on %s\n", ORIG_TYPE_NAME(type)); +#endif +#ifdef __DEBUG_VERBOSE + debug_tree(type); +#endif + randomize_type(type); + + return; +} + +static struct attribute_spec randomize_layout_attr = { }; +static struct attribute_spec no_randomize_layout_attr = { }; +static struct attribute_spec randomize_considered_attr = { }; +static struct attribute_spec randomize_performed_attr = { }; + +static void register_attributes(void *event_data, void *data) +{ + randomize_layout_attr.name = "randomize_layout"; + randomize_layout_attr.type_required = true; + randomize_layout_attr.handler = handle_randomize_layout_attr; + randomize_layout_attr.affects_type_identity = true; + + no_randomize_layout_attr.name = "no_randomize_layout"; + no_randomize_layout_attr.type_required = true; + no_randomize_layout_attr.handler = handle_randomize_layout_attr; + no_randomize_layout_attr.affects_type_identity = true; + + randomize_considered_attr.name = "randomize_considered"; + randomize_considered_attr.type_required = true; + randomize_considered_attr.handler = handle_randomize_considered_attr; + + randomize_performed_attr.name = "randomize_performed"; + randomize_performed_attr.type_required = true; + randomize_performed_attr.handler = handle_randomize_performed_attr; + + register_attribute(&randomize_layout_attr); + register_attribute(&no_randomize_layout_attr); + register_attribute(&randomize_considered_attr); + register_attribute(&randomize_performed_attr); +} + +static void check_bad_casts_in_constructor(tree var, tree init) +{ + unsigned HOST_WIDE_INT idx; + tree field, val; + tree field_type, val_type; + + FOR_EACH_CONSTRUCTOR_ELT(CONSTRUCTOR_ELTS(init), idx, field, val) { + if (TREE_CODE(val) == CONSTRUCTOR) { + check_bad_casts_in_constructor(var, val); + continue; + } + + /* pipacs' plugin creates franken-arrays that differ from those produced by + normal code which all have valid 'field' trees. work around this */ + if (field == NULL_TREE) + continue; + field_type = TREE_TYPE(field); + val_type = TREE_TYPE(val); + + if (TREE_CODE(field_type) != POINTER_TYPE || TREE_CODE(val_type) != POINTER_TYPE) + continue; + + if (field_type == val_type) + continue; + + field_type = TYPE_MAIN_VARIANT(strip_array_types(TYPE_MAIN_VARIANT(TREE_TYPE(field_type)))); + val_type = TYPE_MAIN_VARIANT(strip_array_types(TYPE_MAIN_VARIANT(TREE_TYPE(val_type)))); + + if (field_type == void_type_node) + continue; + if (field_type == val_type) + continue; + if (TREE_CODE(val_type) != RECORD_TYPE) + continue; + + if (!lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(val_type))) + continue; + MISMATCH(DECL_SOURCE_LOCATION(var), "constructor\n", TYPE_MAIN_VARIANT(field_type), TYPE_MAIN_VARIANT(val_type)); + } +} + +/* derived from the constify plugin */ +static void check_global_variables(void *event_data, void *data) +{ + struct varpool_node *node; + tree init; + + FOR_EACH_VARIABLE(node) { + tree var = NODE_DECL(node); + init = DECL_INITIAL(var); + if (init == NULL_TREE) + continue; + + if (TREE_CODE(init) != CONSTRUCTOR) + continue; + + check_bad_casts_in_constructor(var, init); + } +} + +static bool dominated_by_is_err(const_tree rhs, basic_block bb) +{ + basic_block dom; + gimple dom_stmt; + gimple call_stmt; + const_tree dom_lhs; + const_tree poss_is_err_cond; + const_tree poss_is_err_func; + const_tree is_err_arg; + + dom = get_immediate_dominator(CDI_DOMINATORS, bb); + if (!dom) + return false; + + dom_stmt = last_stmt(dom); + if (!dom_stmt) + return false; + + if (gimple_code(dom_stmt) != GIMPLE_COND) + return false; + + if (gimple_cond_code(dom_stmt) != NE_EXPR) + return false; + + if (!integer_zerop(gimple_cond_rhs(dom_stmt))) + return false; + + poss_is_err_cond = gimple_cond_lhs(dom_stmt); + + if (TREE_CODE(poss_is_err_cond) != SSA_NAME) + return false; + + call_stmt = SSA_NAME_DEF_STMT(poss_is_err_cond); + + if (gimple_code(call_stmt) != GIMPLE_CALL) + return false; + + dom_lhs = gimple_get_lhs(call_stmt); + poss_is_err_func = gimple_call_fndecl(call_stmt); + if (!poss_is_err_func) + return false; + if (dom_lhs != poss_is_err_cond) + return false; + if (strcmp(DECL_NAME_POINTER(poss_is_err_func), "IS_ERR")) + return false; + + is_err_arg = gimple_call_arg(call_stmt, 0); + if (!is_err_arg) + return false; + + if (is_err_arg != rhs) + return false; + + return true; +} + +static void handle_local_var_initializers(void) +{ + tree var; + unsigned int i; + + FOR_EACH_LOCAL_DECL(cfun, i, var) { + tree init = DECL_INITIAL(var); + if (!init) + continue; + if (TREE_CODE(init) != CONSTRUCTOR) + continue; + check_bad_casts_in_constructor(var, init); + } +} + +/* + * iterate over all statements to find "bad" casts: + * those where the address of the start of a structure is cast + * to a pointer of a structure of a different type, or a + * structure pointer type is cast to a different structure pointer type + */ +static unsigned int find_bad_casts_execute(void) +{ + basic_block bb; + + handle_local_var_initializers(); + + FOR_EACH_BB_FN(bb, cfun) { + gimple_stmt_iterator gsi; + + for (gsi = gsi_start_bb(bb); !gsi_end_p(gsi); gsi_next(&gsi)) { + gimple stmt; + const_tree lhs; + const_tree lhs_type; + const_tree rhs1; + const_tree rhs_type; + const_tree ptr_lhs_type; + const_tree ptr_rhs_type; + const_tree op0; + const_tree op0_type; + enum tree_code rhs_code; + + stmt = gsi_stmt(gsi); + +#ifdef __DEBUG_PLUGIN +#ifdef __DEBUG_VERBOSE + debug_gimple_stmt(stmt); + debug_tree(gimple_get_lhs(stmt)); +#endif +#endif + + if (gimple_code(stmt) != GIMPLE_ASSIGN) + continue; + +#ifdef __DEBUG_PLUGIN +#ifdef __DEBUG_VERBOSE + debug_tree(gimple_assign_rhs1(stmt)); +#endif +#endif + + + rhs_code = gimple_assign_rhs_code(stmt); + + if (rhs_code != ADDR_EXPR && rhs_code != SSA_NAME) + continue; + + lhs = gimple_get_lhs(stmt); + lhs_type = TREE_TYPE(lhs); + rhs1 = gimple_assign_rhs1(stmt); + rhs_type = TREE_TYPE(rhs1); + + if (TREE_CODE(rhs_type) != POINTER_TYPE || + TREE_CODE(lhs_type) != POINTER_TYPE) + continue; + + ptr_lhs_type = TYPE_MAIN_VARIANT(strip_array_types(TYPE_MAIN_VARIANT(TREE_TYPE(lhs_type)))); + ptr_rhs_type = TYPE_MAIN_VARIANT(strip_array_types(TYPE_MAIN_VARIANT(TREE_TYPE(rhs_type)))); + + if (ptr_rhs_type == void_type_node) + continue; + + if (ptr_lhs_type == void_type_node) + continue; + + if (dominated_by_is_err(rhs1, bb)) + continue; + + if (TREE_CODE(ptr_rhs_type) != RECORD_TYPE) { +#ifndef __DEBUG_PLUGIN + if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(ptr_lhs_type))) +#endif + MISMATCH(gimple_location(stmt), "rhs", ptr_lhs_type, ptr_rhs_type); + continue; + } + + if (rhs_code == SSA_NAME && ptr_lhs_type == ptr_rhs_type) + continue; + + if (rhs_code == ADDR_EXPR) { + op0 = TREE_OPERAND(rhs1, 0); + + if (op0 == NULL_TREE) + continue; + + if (TREE_CODE(op0) != VAR_DECL) + continue; + + op0_type = TYPE_MAIN_VARIANT(strip_array_types(TYPE_MAIN_VARIANT(TREE_TYPE(op0)))); + if (op0_type == ptr_lhs_type) + continue; + +#ifndef __DEBUG_PLUGIN + if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(op0_type))) +#endif + MISMATCH(gimple_location(stmt), "op0", ptr_lhs_type, op0_type); + } else { + const_tree ssa_name_var = SSA_NAME_VAR(rhs1); + /* skip bogus type casts introduced by container_of */ + if (ssa_name_var != NULL_TREE && DECL_NAME(ssa_name_var) && + !strcmp((const char *)DECL_NAME_POINTER(ssa_name_var), "__mptr")) + continue; +#ifndef __DEBUG_PLUGIN + if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(ptr_rhs_type))) +#endif + MISMATCH(gimple_location(stmt), "ssa", ptr_lhs_type, ptr_rhs_type); + } + + } + } + return 0; +} + +#define PASS_NAME find_bad_casts +#define NO_GATE +#define TODO_FLAGS_FINISH TODO_dump_func +#include "gcc-generate-gimple-pass.h" + +__visible int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version) +{ + int i; + const char * const plugin_name = plugin_info->base_name; + const int argc = plugin_info->argc; + const struct plugin_argument * const argv = plugin_info->argv; + bool enable = true; + int obtained_seed = 0; + struct register_pass_info find_bad_casts_pass_info; + + find_bad_casts_pass_info.pass = make_find_bad_casts_pass(); + find_bad_casts_pass_info.reference_pass_name = "ssa"; + find_bad_casts_pass_info.ref_pass_instance_number = 1; + find_bad_casts_pass_info.pos_op = PASS_POS_INSERT_AFTER; + + if (!plugin_default_version_check(version, &gcc_version)) { + error(G_("incompatible gcc/plugin versions")); + return 1; + } + + if (strncmp(lang_hooks.name, "GNU C", 5) && !strncmp(lang_hooks.name, "GNU C+", 6)) { + inform(UNKNOWN_LOCATION, G_("%s supports C only, not %s"), plugin_name, lang_hooks.name); + enable = false; + } + + for (i = 0; i < argc; ++i) { + if (!strcmp(argv[i].key, "disable")) { + enable = false; + continue; + } + if (!strcmp(argv[i].key, "performance-mode")) { + performance_mode = 1; + continue; + } + error(G_("unknown option '-fplugin-arg-%s-%s'"), plugin_name, argv[i].key); + } + + if (strlen(randstruct_seed) != 64) { + error(G_("invalid seed value supplied for %s plugin"), plugin_name); + return 1; + } + obtained_seed = sscanf(randstruct_seed, "%016llx%016llx%016llx%016llx", + &shuffle_seed[0], &shuffle_seed[1], &shuffle_seed[2], &shuffle_seed[3]); + if (obtained_seed != 4) { + error(G_("Invalid seed supplied for %s plugin"), plugin_name); + return 1; + } + + register_callback(plugin_name, PLUGIN_INFO, NULL, &randomize_layout_plugin_info); + if (enable) { + register_callback(plugin_name, PLUGIN_ALL_IPA_PASSES_START, check_global_variables, NULL); + register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL, &find_bad_casts_pass_info); + register_callback(plugin_name, PLUGIN_FINISH_TYPE, finish_type, NULL); + register_callback(plugin_name, PLUGIN_FINISH_DECL, randomize_layout_finish_decl, NULL); + } + register_callback(plugin_name, PLUGIN_ATTRIBUTES, register_attributes, NULL); + + return 0; +} |