diff options
| -rw-r--r-- | gdb/Makefile.in | 1 | ||||
| -rw-r--r-- | gdb/aarch64-linux-nat.c | 42 | ||||
| -rw-r--r-- | gdb/arch/aarch64-mte-linux.c | 34 | ||||
| -rw-r--r-- | gdb/arch/aarch64-mte-linux.h | 10 | ||||
| -rw-r--r-- | gdb/configure.nat | 3 | ||||
| -rw-r--r-- | gdb/configure.tgt | 1 | ||||
| -rw-r--r-- | gdb/nat/aarch64-mte-linux-ptrace.c | 195 | ||||
| -rw-r--r-- | gdb/nat/aarch64-mte-linux-ptrace.h | 17 |
8 files changed, 302 insertions, 1 deletions
diff --git a/gdb/Makefile.in b/gdb/Makefile.in index d43bdf4..dc126bd 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -680,6 +680,7 @@ ALL_64_TARGET_OBS = \ amd64-windows-tdep.o \ arch/aarch64.o \ arch/aarch64-insn.o \ + arch/aarch64-mte-linux.o \ arch/amd64.o \ ia64-linux-tdep.o \ ia64-tdep.o \ diff --git a/gdb/aarch64-linux-nat.c b/gdb/aarch64-linux-nat.c index 63e1395..5b245d0 100644 --- a/gdb/aarch64-linux-nat.c +++ b/gdb/aarch64-linux-nat.c @@ -52,6 +52,8 @@ #include "arch/aarch64-mte-linux.h" +#include "nat/aarch64-mte-linux-ptrace.h" + #ifndef TRAP_HWBKPT #define TRAP_HWBKPT 0x0004 #endif @@ -102,6 +104,16 @@ public: override; struct gdbarch *thread_architecture (ptid_t) override; + + bool supports_memory_tagging () override; + + /* Read memory allocation tags from memory via PTRACE. */ + int fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags) override; + + /* Write allocation tags to memory via PTRACE. */ + int store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags) override; }; static aarch64_linux_nat_target the_aarch64_linux_nat_target; @@ -1011,6 +1023,36 @@ aarch64_linux_nat_target::thread_architecture (ptid_t ptid) return gdbarch_find_by_info (info); } +/* Implement the "supports_memory_tagging" target_ops method. */ + +bool +aarch64_linux_nat_target::supports_memory_tagging () +{ + return (linux_get_hwcap2 (this) & HWCAP2_MTE) != 0; +} + +/* Implement the "fetch_memtags" target_ops method. */ + +int +aarch64_linux_nat_target::fetch_memtags (CORE_ADDR address, size_t len, + gdb::byte_vector &tags) +{ + int tid = inferior_ptid.lwp (); + + return aarch64_mte_fetch_memtags (tid, address, len, tags); +} + +/* Implement the "store_memtags" target_ops method. */ + +int +aarch64_linux_nat_target::store_memtags (CORE_ADDR address, size_t len, + const gdb::byte_vector &tags) +{ + int tid = inferior_ptid.lwp (); + + return aarch64_mte_store_memtags (tid, address, len, tags); +} + /* Define AArch64 maintenance commands. */ static void diff --git a/gdb/arch/aarch64-mte-linux.c b/gdb/arch/aarch64-mte-linux.c new file mode 100644 index 0000000..ce603b0 --- /dev/null +++ b/gdb/arch/aarch64-mte-linux.c @@ -0,0 +1,34 @@ +/* Common Linux target-dependent functionality for AArch64 MTE + + Copyright (C) 2020 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "arch/aarch64-mte-linux.h" + +/* See arch/aarch64-mte-linux.h */ + +int +get_tag_granules (CORE_ADDR addr, size_t len, unsigned int granule_size) +{ + /* Start address */ + CORE_ADDR s_addr = align_down (addr, granule_size); + /* End address */ + CORE_ADDR e_addr = align_down (addr + len, granule_size); + + /* We always have at least 1 granule. */ + return 1 + (e_addr - s_addr) / granule_size; +} diff --git a/gdb/arch/aarch64-mte-linux.h b/gdb/arch/aarch64-mte-linux.h index 423d4de..d3f4485 100644 --- a/gdb/arch/aarch64-mte-linux.h +++ b/gdb/arch/aarch64-mte-linux.h @@ -20,6 +20,8 @@ #ifndef ARCH_AARCH64_LINUX_H #define ARCH_AARCH64_LINUX_H +#include "gdbsupport/common-defs.h" + /* Feature check for Memory Tagging Extension. */ #ifndef HWCAP2_MTE #define HWCAP2_MTE (1 << 18) @@ -28,4 +30,12 @@ /* The MTE regset consists of 2 registers of 64-bit size. */ #define AARCH64_LINUX_SIZEOF_MTE (2 * 64) +/* We have one tag per 16 bytes of memory. */ +#define MTE_GRANULE_SIZE 16 + +/* Return the number of tag granules in the memory range + [ADDR, ADDR + LEN) given GRANULE_SIZE. */ +extern int get_tag_granules (CORE_ADDR addr, size_t len, + unsigned int granule_size); + #endif /* ARCH_AARCH64_LINUX_H */ diff --git a/gdb/configure.nat b/gdb/configure.nat index 6ea2583..1a91ea4 100644 --- a/gdb/configure.nat +++ b/gdb/configure.nat @@ -236,7 +236,8 @@ case ${gdb_host} in NATDEPFILES="${NATDEPFILES} aarch64-linux-nat.o \ aarch32-linux-nat.o nat/aarch64-linux-hw-point.o \ nat/aarch64-linux.o \ - nat/aarch64-sve-linux-ptrace.o" + nat/aarch64-sve-linux-ptrace.o \ + nat/aarch64-mte-linux-ptrace.o" ;; arm) # Host: ARM based machine running GNU/Linux diff --git a/gdb/configure.tgt b/gdb/configure.tgt index d66f01b..2082661 100644 --- a/gdb/configure.tgt +++ b/gdb/configure.tgt @@ -124,6 +124,7 @@ aarch64*-*-freebsd*) aarch64*-*-linux*) # Target: AArch64 linux gdb_target_obs="aarch64-linux-tdep.o arch/aarch64.o\ + arch/aarch64-mte-linux.o \ arch/arm.o arch/arm-linux.o arch/arm-get-next-pcs.o \ arm-tdep.o arm-linux-tdep.o \ glibc-tdep.o linux-tdep.o solib-svr4.o \ diff --git a/gdb/nat/aarch64-mte-linux-ptrace.c b/gdb/nat/aarch64-mte-linux-ptrace.c new file mode 100644 index 0000000..4cf4b56 --- /dev/null +++ b/gdb/nat/aarch64-mte-linux-ptrace.c @@ -0,0 +1,195 @@ +/* Common Linux native ptrace code for AArch64 MTE. + + Copyright (C) 2020 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "gdbsupport/common-defs.h" +#include "gdbsupport/byte-vector.h" + +#include "arch/aarch64.h" +#include "arch/aarch64-mte-linux.h" +#include "nat/aarch64-linux.h" +#include "nat/aarch64-mte-linux-ptrace.h" + +#include "linux-ptrace.h" +#include <sys/uio.h> + +/* Helper function to display various possible errors when reading + MTE tags. */ + +static void +aarch64_mte_linux_peek_error (int error) +{ + switch (error) + { + case EIO: + perror_with_name (_("PEEKMTETAGS not supported")); + break; + case EFAULT: + perror_with_name (_("Couldn't fetch allocation tags")); + break; + case EOPNOTSUPP: + perror_with_name (_("PROT_ME not enabled for requested address")); + default: + perror_with_name (_("Unknown MTE error")); + break; + } +} + +/* Helper function to display various possible errors when writing + MTE tags. */ + +static void +aarch64_mte_linux_poke_error (int error) +{ + switch (error) + { + case EIO: + perror_with_name (_("POKEMTETAGS not supported")); + break; + case EFAULT: + perror_with_name (_("Couldn't store allocation tags")); + break; + case EOPNOTSUPP: + perror_with_name (_("PROT_ME not enabled for requested address")); + default: + perror_with_name (_("Unknown MTE error")); + break; + } +} + +/* Helper to prepare a vector of tags to be passed on to the kernel. The + main purpose of this function is to optimize the number of calls to + ptrace if we're writing too many tags at once, like a pattern fill + request. + + Return a vector of tags of up to MAX_SIZE size, containing the tags that + must be passed on to the kernel. GRANULES is the number of tag granules to + be modified. */ + +static gdb::byte_vector +prepare_tag_vector (size_t granules, const gdb::byte_vector &tags, + size_t max_size) +{ + gdb::byte_vector t (0); + + if (granules == 0) + return t; + + gdb_assert (tags.size () > 0 && max_size > 0); + + if (granules > TAGS_MAX_SIZE) + t.resize (TAGS_MAX_SIZE); + else + t.resize (granules); + + size_t tag_count = tags.size (); + + for (size_t i = 0; i < t.size (); i++) + t[i] = tags[i % tag_count]; + + return t; +} + +/* See nat/aarch64-mte-linux-ptrace.h */ + +int +aarch64_mte_fetch_memtags (int tid, CORE_ADDR address, size_t len, + gdb::byte_vector &tags) +{ + size_t ntags = get_tag_granules (address, len, MTE_GRANULE_SIZE); + gdb_byte tagbuf[ntags]; + + struct iovec iovec; + iovec.iov_base = tagbuf; + iovec.iov_len = ntags; + + tags.clear (); + bool done_reading = false; + + /* The kernel may return less tags than we requested. Loop until we've read + all the requested tags or until we get an error. */ + while (!done_reading) + { + /* Attempt to read ntags allocation tags from the kernel. */ + if (ptrace (PTRACE_PEEKMTETAGS, tid, address, &iovec) < 0) + aarch64_mte_linux_peek_error (errno); + + /* Make sure the kernel returned at least one tag. */ + if (iovec.iov_len <= 0) + { + tags.clear (); + return 1; + } + + /* Copy the tags the kernel returned. */ + for (size_t i = 0; i < iovec.iov_len; i++) + tags.push_back (tagbuf[i]); + + /* Are we done reading tags? */ + if (tags.size () == ntags) + done_reading = true; + else + { + address += iovec.iov_len * MTE_GRANULE_SIZE; + iovec.iov_len = ntags - iovec.iov_len; + } + } + return 0; +} + +/* See nat/aarch64-mte-linux-ptrace.h */ + +int +aarch64_mte_store_memtags (int tid, CORE_ADDR address, size_t len, + const gdb::byte_vector &tags) +{ + if (tags.size () == 0) + return 0; + + /* Get the number of tags we need to write. */ + size_t ntags = get_tag_granules (address, len, MTE_GRANULE_SIZE); + + gdb::byte_vector t = prepare_tag_vector (ntags, tags, TAGS_MAX_SIZE); + gdb::byte_vector tags_left = tags; + + /* Write all the tags, TAGS_MAX_SIZE blocks at a time. */ + while (t.size () != 0) + { + struct iovec iovec; + iovec.iov_base = t.data (); + iovec.iov_len = t.size (); + + /* Request the kernel to update the allocation tags. */ + if (ptrace (PTRACE_POKEMTETAGS, tid, address, &iovec) < 0) + aarch64_mte_linux_poke_error (errno); + + /* Make sure the kernel wrote at least one tag. */ + if (iovec.iov_len <= 0) + return 1; + + /* Update the tag vector based on how many tags the kernel actually + wrote. */ + auto it = tags_left.begin (); + tags_left.erase (it, it + iovec.iov_len - 1); + address += iovec.iov_len * MTE_GRANULE_SIZE; + ntags -= iovec.iov_len; + t = prepare_tag_vector (ntags, tags_left, TAGS_MAX_SIZE); + } + + return 0; +} diff --git a/gdb/nat/aarch64-mte-linux-ptrace.h b/gdb/nat/aarch64-mte-linux-ptrace.h index 099b644..7ba6f01 100644 --- a/gdb/nat/aarch64-mte-linux-ptrace.h +++ b/gdb/nat/aarch64-mte-linux-ptrace.h @@ -30,4 +30,21 @@ #define PTRACE_POKEMTETAGS 34 #endif +/* Maximum number of tags to pass at once to the kernel. */ +#define TAGS_MAX_SIZE 4096 + +/* Read the allocation tags from memory range [ADDRESS, ADDRESS + LEN) + into TAGS. + + Return 0 if successful and non-zero otherwise. */ +extern int aarch64_mte_fetch_memtags (int tid, CORE_ADDR address, size_t len, + gdb::byte_vector &tags); + +/* Write the TAGS allocation tags to the memory range + [ADDRESS, ADDRESS + LEN). + + Return 0 if successful and non-zero otherwise. */ +extern int aarch64_mte_store_memtags (int tid, CORE_ADDR address, size_t len, + const gdb::byte_vector &tags); + #endif /* NAT_AARCH64_MTE_LINUX_PTRACE_H */ |