From: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
To: gdb-patches@sourceware.org
Cc: Luis Machado <luis.machado@arm.com>,
Thiago Jung Bauermann <thiago.bauermann@linaro.org>
Subject: [PATCH v2 2/6] gdbserver: Add PID parameter to linux_get_auxv and linux_get_hwcap
Date: Sat, 26 Nov 2022 02:04:48 +0000 [thread overview]
Message-ID: <20221126020452.1686509-3-thiago.bauermann@linaro.org> (raw)
In-Reply-To: <20221126020452.1686509-1-thiago.bauermann@linaro.org>
This patch doesn't change gdbserver behaviour, but after later changes are
made it avoids a null pointer dereference when HWCAP needs to be obtained
for a specific process while current_thread is nullptr.
Fixing linux_read_auxv, linux_get_hwcap and linux_get_hwcap2 to take a PID
parameter seems more correct than setting current_thread in one particular
code path.
Changes are propagated to allow passing the new parameter through the call
chain.
---
gdbserver/linux-aarch64-low.cc | 7 ++++---
gdbserver/linux-arm-low.cc | 2 +-
gdbserver/linux-low.cc | 18 +++++++++---------
gdbserver/linux-low.h | 9 ++++-----
gdbserver/linux-ppc-low.cc | 6 +++---
gdbserver/linux-s390-low.cc | 2 +-
gdbserver/netbsd-low.cc | 4 +---
gdbserver/netbsd-low.h | 2 +-
gdbserver/server.cc | 2 +-
gdbserver/target.cc | 4 ++--
gdbserver/target.h | 2 +-
11 files changed, 28 insertions(+), 30 deletions(-)
diff --git a/gdbserver/linux-aarch64-low.cc b/gdbserver/linux-aarch64-low.cc
index db5086962612..a6ed68f93029 100644
--- a/gdbserver/linux-aarch64-low.cc
+++ b/gdbserver/linux-aarch64-low.cc
@@ -823,12 +823,13 @@ aarch64_target::low_arch_setup ()
if (is_elf64)
{
struct aarch64_features features;
+ int pid = pid_of (current_thread);
features.vq = aarch64_sve_get_vq (tid);
/* A-profile PAC is 64-bit only. */
- features.pauth = linux_get_hwcap (8) & AARCH64_HWCAP_PACA;
+ features.pauth = (linux_get_hwcap (pid, 8) & AARCH64_HWCAP_PACA);
/* A-profile MTE is 64-bit only. */
- features.mte = linux_get_hwcap2 (8) & HWCAP2_MTE;
+ features.mte = linux_get_hwcap2 (pid, 8) & HWCAP2_MTE;
features.tls = true;
current_process ()->tdesc = aarch64_linux_read_description (features);
@@ -3299,7 +3300,7 @@ aarch64_target::supports_memory_tagging ()
#endif
}
- return (linux_get_hwcap2 (8) & HWCAP2_MTE) != 0;
+ return (linux_get_hwcap2 (pid_of (current_thread), 8) & HWCAP2_MTE) != 0;
}
bool
diff --git a/gdbserver/linux-arm-low.cc b/gdbserver/linux-arm-low.cc
index a458b0f14a68..1420909626e8 100644
--- a/gdbserver/linux-arm-low.cc
+++ b/gdbserver/linux-arm-low.cc
@@ -958,7 +958,7 @@ get_next_pcs_syscall_next_pc (struct arm_get_next_pcs *self)
static const struct target_desc *
arm_read_description (void)
{
- unsigned long arm_hwcap = linux_get_hwcap (4);
+ unsigned long arm_hwcap = linux_get_hwcap (pid_of (current_thread), 4);
if (arm_hwcap & HWCAP_IWMMXT)
return arm_linux_read_description (ARM_FP_TYPE_IWMMXT);
diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc
index a896b37528b6..fc496275d6a3 100644
--- a/gdbserver/linux-low.cc
+++ b/gdbserver/linux-low.cc
@@ -5480,12 +5480,11 @@ linux_process_target::supports_read_auxv ()
to debugger memory starting at MYADDR. */
int
-linux_process_target::read_auxv (CORE_ADDR offset, unsigned char *myaddr,
- unsigned int len)
+linux_process_target::read_auxv (int pid, CORE_ADDR offset,
+ unsigned char *myaddr, unsigned int len)
{
char filename[PATH_MAX];
int fd, n;
- int pid = lwpid_of (current_thread);
xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
@@ -6979,14 +6978,15 @@ linux_get_pc_64bit (struct regcache *regcache)
/* See linux-low.h. */
int
-linux_get_auxv (int wordsize, CORE_ADDR match, CORE_ADDR *valp)
+linux_get_auxv (int pid, int wordsize, CORE_ADDR match, CORE_ADDR *valp)
{
gdb_byte *data = (gdb_byte *) alloca (2 * wordsize);
int offset = 0;
gdb_assert (wordsize == 4 || wordsize == 8);
- while (the_target->read_auxv (offset, data, 2 * wordsize) == 2 * wordsize)
+ while (the_target->read_auxv (pid, offset, data, 2 * wordsize)
+ == 2 * wordsize)
{
if (wordsize == 4)
{
@@ -7016,20 +7016,20 @@ linux_get_auxv (int wordsize, CORE_ADDR match, CORE_ADDR *valp)
/* See linux-low.h. */
CORE_ADDR
-linux_get_hwcap (int wordsize)
+linux_get_hwcap (int pid, int wordsize)
{
CORE_ADDR hwcap = 0;
- linux_get_auxv (wordsize, AT_HWCAP, &hwcap);
+ linux_get_auxv (pid, wordsize, AT_HWCAP, &hwcap);
return hwcap;
}
/* See linux-low.h. */
CORE_ADDR
-linux_get_hwcap2 (int wordsize)
+linux_get_hwcap2 (int pid, int wordsize)
{
CORE_ADDR hwcap2 = 0;
- linux_get_auxv (wordsize, AT_HWCAP2, &hwcap2);
+ linux_get_auxv (pid, wordsize, AT_HWCAP2, &hwcap2);
return hwcap2;
}
diff --git a/gdbserver/linux-low.h b/gdbserver/linux-low.h
index 1594f063f47c..182a540f3bb3 100644
--- a/gdbserver/linux-low.h
+++ b/gdbserver/linux-low.h
@@ -178,7 +178,7 @@ class linux_process_target : public process_stratum_target
bool supports_read_auxv () override;
- int read_auxv (CORE_ADDR offset, unsigned char *myaddr,
+ int read_auxv (int pid, CORE_ADDR offset, unsigned char *myaddr,
unsigned int len) override;
int insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
@@ -946,17 +946,16 @@ extern int have_ptrace_getregset;
*VALP and return 1. If not found or if there is an error, return
0. */
-int linux_get_auxv (int wordsize, CORE_ADDR match,
- CORE_ADDR *valp);
+int linux_get_auxv (int pid, int wordsize, CORE_ADDR match, CORE_ADDR *valp);
/* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
WORDSIZE. If no entry was found, return zero. */
-CORE_ADDR linux_get_hwcap (int wordsize);
+CORE_ADDR linux_get_hwcap (int pid, int wordsize);
/* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
WORDSIZE. If no entry was found, return zero. */
-CORE_ADDR linux_get_hwcap2 (int wordsize);
+CORE_ADDR linux_get_hwcap2 (int pid, int wordsize);
#endif /* GDBSERVER_LINUX_LOW_H */
diff --git a/gdbserver/linux-ppc-low.cc b/gdbserver/linux-ppc-low.cc
index 08824887003b..1db20d998ffd 100644
--- a/gdbserver/linux-ppc-low.cc
+++ b/gdbserver/linux-ppc-low.cc
@@ -894,8 +894,8 @@ ppc_target::low_arch_setup ()
/* The value of current_process ()->tdesc needs to be set for this
call. */
- ppc_hwcap = linux_get_hwcap (features.wordsize);
- ppc_hwcap2 = linux_get_hwcap2 (features.wordsize);
+ ppc_hwcap = linux_get_hwcap (pid_of (current_thread), features.wordsize);
+ ppc_hwcap2 = linux_get_hwcap2 (pid_of (current_thread), features.wordsize);
features.isa205 = ppc_linux_has_isa205 (ppc_hwcap);
@@ -1097,7 +1097,7 @@ is_elfv2_inferior (void)
const struct target_desc *tdesc = current_process ()->tdesc;
int wordsize = register_size (tdesc, 0);
- if (!linux_get_auxv (wordsize, AT_PHDR, &phdr))
+ if (!linux_get_auxv (pid_of (current_thread), wordsize, AT_PHDR, &phdr))
return def_res;
/* Assume ELF header is at the beginning of the page where program headers
diff --git a/gdbserver/linux-s390-low.cc b/gdbserver/linux-s390-low.cc
index 5adc28070574..2d030a806350 100644
--- a/gdbserver/linux-s390-low.cc
+++ b/gdbserver/linux-s390-low.cc
@@ -592,7 +592,7 @@ s390_target::low_arch_setup ()
/* Determine word size and HWCAP. */
int pid = pid_of (current_thread);
int wordsize = s390_get_wordsize (pid);
- unsigned long hwcap = linux_get_hwcap (wordsize);
+ unsigned long hwcap = linux_get_hwcap (pid, wordsize);
/* Check whether the kernel supports extra register sets. */
int have_regset_last_break
diff --git a/gdbserver/netbsd-low.cc b/gdbserver/netbsd-low.cc
index f05bcd4e173f..03af80049457 100644
--- a/gdbserver/netbsd-low.cc
+++ b/gdbserver/netbsd-low.cc
@@ -581,11 +581,9 @@ netbsd_read_auxv(pid_t pid, void *offs, void *addr, size_t len)
to debugger memory starting at MYADDR. */
int
-netbsd_process_target::read_auxv (CORE_ADDR offset,
+netbsd_process_target::read_auxv (int pid, CORE_ADDR offset,
unsigned char *myaddr, unsigned int len)
{
- pid_t pid = pid_of (current_thread);
-
return netbsd_read_auxv (pid, (void *) (intptr_t) offset, myaddr, len);
}
diff --git a/gdbserver/netbsd-low.h b/gdbserver/netbsd-low.h
index 06b4fd613571..eced7b3dd860 100644
--- a/gdbserver/netbsd-low.h
+++ b/gdbserver/netbsd-low.h
@@ -77,7 +77,7 @@ class netbsd_process_target : public process_stratum_target
bool supports_read_auxv () override;
- int read_auxv (CORE_ADDR offset, unsigned char *myaddr,
+ int read_auxv (int pid, CORE_ADDR offset, unsigned char *myaddr,
unsigned int len) override;
bool supports_hardware_single_step () override;
diff --git a/gdbserver/server.cc b/gdbserver/server.cc
index aaef38e00622..63c323071670 100644
--- a/gdbserver/server.cc
+++ b/gdbserver/server.cc
@@ -1443,7 +1443,7 @@ handle_qxfer_auxv (const char *annex,
if (annex[0] != '\0' || current_thread == NULL)
return -1;
- return the_target->read_auxv (offset, readbuf, len);
+ return the_target->read_auxv (pid_of (current_thread), offset, readbuf, len);
}
/* Handle qXfer:exec-file:read. */
diff --git a/gdbserver/target.cc b/gdbserver/target.cc
index c06a67600b1f..3651dbb9e862 100644
--- a/gdbserver/target.cc
+++ b/gdbserver/target.cc
@@ -344,8 +344,8 @@ process_stratum_target::supports_read_auxv ()
}
int
-process_stratum_target::read_auxv (CORE_ADDR offset, unsigned char *myaddr,
- unsigned int len)
+process_stratum_target::read_auxv (int pid, CORE_ADDR offset,
+ unsigned char *myaddr, unsigned int len)
{
gdb_assert_not_reached ("target op read_auxv not supported");
}
diff --git a/gdbserver/target.h b/gdbserver/target.h
index 18ab969dda70..fe7a80b645bc 100644
--- a/gdbserver/target.h
+++ b/gdbserver/target.h
@@ -175,7 +175,7 @@ class process_stratum_target
/* Read auxiliary vector data from the inferior process.
Read LEN bytes at OFFSET into a buffer at MYADDR. */
- virtual int read_auxv (CORE_ADDR offset, unsigned char *myaddr,
+ virtual int read_auxv (int pid, CORE_ADDR offset, unsigned char *myaddr,
unsigned int len);
/* Returns true if GDB Z breakpoint type TYPE is supported, false
next prev parent reply other threads:[~2022-11-26 2:05 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-26 2:04 [PATCH v2 0/6] gdbserver improvements for AArch64 SVE support Thiago Jung Bauermann
2022-11-26 2:04 ` [PATCH v2 1/6] gdbserver: Add asserts in register_size and register_data functions Thiago Jung Bauermann
2022-11-28 11:51 ` Luis Machado
2022-11-29 2:53 ` Thiago Jung Bauermann
2022-11-28 14:48 ` Simon Marchi
2022-11-28 14:53 ` Simon Marchi
2022-11-29 2:52 ` Thiago Jung Bauermann
2022-11-29 2:43 ` Thiago Jung Bauermann
2022-11-26 2:04 ` Thiago Jung Bauermann [this message]
2022-11-28 11:50 ` [PATCH v2 2/6] gdbserver: Add PID parameter to linux_get_auxv and linux_get_hwcap Luis Machado
2022-11-28 15:01 ` Simon Marchi
2022-11-29 3:10 ` Thiago Jung Bauermann
2022-11-28 15:07 ` Simon Marchi
2022-11-28 15:20 ` Luis Machado
2022-11-29 3:17 ` Thiago Jung Bauermann
2022-11-26 2:04 ` [PATCH v2 3/6] gdbserver/linux-aarch64: Factor out function to get aarch64_features Thiago Jung Bauermann
2022-11-28 11:54 ` Luis Machado
2022-11-29 3:19 ` Thiago Jung Bauermann
2022-11-28 15:12 ` Simon Marchi
2022-11-29 3:26 ` Thiago Jung Bauermann
2022-11-26 2:04 ` [PATCH v2 4/6] gdbserver/linux-aarch64: When thread stops, update its target description Thiago Jung Bauermann
2022-11-28 12:06 ` Luis Machado
2022-11-29 3:59 ` Thiago Jung Bauermann
2022-11-28 15:47 ` Simon Marchi
2022-11-28 16:01 ` Luis Machado
2022-11-28 16:07 ` Simon Marchi
2022-11-29 4:30 ` Thiago Jung Bauermann
2022-11-26 2:04 ` [PATCH v2 5/6] gdb/aarch64: Factor out most of the thread_architecture method Thiago Jung Bauermann
2022-11-28 12:09 ` Luis Machado
2022-11-29 4:32 ` Thiago Jung Bauermann
2022-11-28 16:09 ` Simon Marchi
2022-11-29 4:33 ` Thiago Jung Bauermann
2022-11-26 2:04 ` [PATCH v2 6/6] gdb/aarch64: Detect vector length changes when debugging remotely Thiago Jung Bauermann
2022-11-28 13:27 ` Luis Machado
2022-12-01 1:15 ` Thiago Jung Bauermann
2022-11-28 16:36 ` Simon Marchi
2022-12-01 3:16 ` Thiago Jung Bauermann
2022-12-01 8:32 ` Luis Machado
2022-12-01 16:16 ` Simon Marchi
2022-11-30 8:43 ` Luis Machado
2022-12-05 22:37 ` Thiago Jung Bauermann
2022-12-07 17:05 ` Luis Machado
2022-12-07 19:25 ` Simon Marchi
2022-12-07 23:01 ` Luis Machado
2022-12-09 2:20 ` Thiago Jung Bauermann
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