From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa1-x34.google.com (mail-oa1-x34.google.com [IPv6:2001:4860:4864:20::34]) by sourceware.org (Postfix) with ESMTPS id C1B94385829E for ; Thu, 8 Sep 2022 06:42:51 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C1B94385829E Received: by mail-oa1-x34.google.com with SMTP id 586e51a60fabf-127d10b4f19so16160640fac.9 for ; Wed, 07 Sep 2022 23:42:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date; bh=rUHSnS9aioNU00EV+GrDr8x7iNZv6VD4RJxypFv7+w4=; b=GSa4u25IaHlWmNBbUNWDJA/VXkaPdTNhrtKO2yihlPGIH06AMOj3fJgH3JPyUXomwr SjoHPnRYe7Mf8rtKPTev69t7Q7UN76BFMp+hU9zFRBbitrA4FOrOtZRUbmxAgDTzatjL lxYGVjjM/BAD9AlCx7mVCID9v36QkD0VjtGkEO+jx6CRyb3Jhn+Axn+V7oO1mekdTMo6 yaYJnpN+kDAfG4PFCGvlCw3MnoUCmT/kDQn200BlqaDwN7bvEy+WWIzYqEaEjOPKW3Bk CrsVxxb5Un2fS6G6f/St5ZaXOW8yiTwPWw9micbI7WRQcQoFTYipFwVI1efFcwEywQAu 7tyg== X-Gm-Message-State: ACgBeo0SJdv7TrX+dhnrd9GR2KnJh5LPJ72viKm6dgMXXPftp7aKWkhC lUSHFd8A1e3KN8OW60w14Btxf87LCEeTZg== X-Google-Smtp-Source: AA6agR5zQP9UHohSw99dunhEALARyDn+McrXPJXb2OntkSaEDwRwNPN8LyrNQBQ8ipSEzePzMfIKgg== X-Received: by 2002:a05:6870:6015:b0:fe:340e:e854 with SMTP id t21-20020a056870601500b000fe340ee854mr1122063oaa.52.1662619371436; Wed, 07 Sep 2022 23:42:51 -0700 (PDT) Received: from localhost ([2804:14d:7e39:8470:8eab:4efc:ca3b:b046]) by smtp.gmail.com with ESMTPSA id n11-20020a056870034b00b00127ebb410a4sm2418272oaf.11.2022.09.07.23.42.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Sep 2022 23:42:50 -0700 (PDT) From: Thiago Jung Bauermann To: gdb-patches@sourceware.org Cc: Thiago Jung Bauermann Subject: [PATCH 2/8] gdbserver: Add thread parameter to linux_get_auxv and linux_get_hwcap Date: Thu, 8 Sep 2022 06:41:45 +0000 Message-Id: <20220908064151.3959930-3-thiago.bauermann@linaro.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220908064151.3959930-1-thiago.bauermann@linaro.org> References: <20220908064151.3959930-1-thiago.bauermann@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-10.9 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 08 Sep 2022 06:42:53 -0000 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 thread_info parameter seems more correct than setting current_thread in one particular code path. Changes are propagated to allow passing the thread parameter through the call chain. --- gdbserver/linux-aarch64-low.cc | 6 +++--- gdbserver/linux-arm-low.cc | 2 +- gdbserver/linux-low.cc | 20 +++++++++++--------- gdbserver/linux-low.h | 10 +++++----- gdbserver/linux-ppc-low.cc | 6 +++--- gdbserver/linux-s390-low.cc | 2 +- gdbserver/netbsd-low.cc | 4 ++-- gdbserver/netbsd-low.h | 4 ++-- gdbserver/server.cc | 2 +- gdbserver/target.cc | 4 ++-- gdbserver/target.h | 4 ++-- 11 files changed, 33 insertions(+), 31 deletions(-) diff --git a/gdbserver/linux-aarch64-low.cc b/gdbserver/linux-aarch64-low.cc index db5086962612..5d4d667dfa42 100644 --- a/gdbserver/linux-aarch64-low.cc +++ b/gdbserver/linux-aarch64-low.cc @@ -826,9 +826,9 @@ aarch64_target::low_arch_setup () 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 (current_thread, 8) & AARCH64_HWCAP_PACA; /* A-profile MTE is 64-bit only. */ - features.mte = linux_get_hwcap2 (8) & HWCAP2_MTE; + features.mte = linux_get_hwcap2 (current_thread, 8) & HWCAP2_MTE; features.tls = true; current_process ()->tdesc = aarch64_linux_read_description (features); @@ -3299,7 +3299,7 @@ aarch64_target::supports_memory_tagging () #endif } - return (linux_get_hwcap2 (8) & HWCAP2_MTE) != 0; + return (linux_get_hwcap2 (current_thread, 8) & HWCAP2_MTE) != 0; } bool diff --git a/gdbserver/linux-arm-low.cc b/gdbserver/linux-arm-low.cc index ab6209a3abc8..d40ce412fe1c 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 (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 2f71360d3bde..9034a1d8fabe 100644 --- a/gdbserver/linux-low.cc +++ b/gdbserver/linux-low.cc @@ -5486,12 +5486,12 @@ 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 (const thread_info *thread, CORE_ADDR offset, + unsigned char *myaddr, unsigned int len) { char filename[PATH_MAX]; int fd, n; - int pid = lwpid_of (current_thread); + int pid = lwpid_of (thread); xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid); @@ -6912,14 +6912,16 @@ 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 (const thread_info *thread, 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 (thread, offset, data, 2 * wordsize) + == 2 * wordsize) { if (wordsize == 4) { @@ -6949,20 +6951,20 @@ 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 (const thread_info *thread, int wordsize) { CORE_ADDR hwcap = 0; - linux_get_auxv (wordsize, AT_HWCAP, &hwcap); + linux_get_auxv (thread, wordsize, AT_HWCAP, &hwcap); return hwcap; } /* See linux-low.h. */ CORE_ADDR -linux_get_hwcap2 (int wordsize) +linux_get_hwcap2 (const thread_info *thread, int wordsize) { CORE_ADDR hwcap2 = 0; - linux_get_auxv (wordsize, AT_HWCAP2, &hwcap2); + linux_get_auxv (thread, wordsize, AT_HWCAP2, &hwcap2); return hwcap2; } diff --git a/gdbserver/linux-low.h b/gdbserver/linux-low.h index 79be31b8f729..bd1ec31dc5a4 100644 --- a/gdbserver/linux-low.h +++ b/gdbserver/linux-low.h @@ -178,8 +178,8 @@ class linux_process_target : public process_stratum_target bool supports_read_auxv () override; - int read_auxv (CORE_ADDR offset, unsigned char *myaddr, - unsigned int len) override; + int read_auxv (const thread_info *thread, CORE_ADDR offset, + unsigned char *myaddr, unsigned int len) override; int insert_point (enum raw_bkpt_type type, CORE_ADDR addr, int size, raw_breakpoint *bp) override; @@ -944,17 +944,17 @@ 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, +int linux_get_auxv (const thread_info *thread, 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 (const thread_info *thread, 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 (const thread_info *thread, int wordsize); #endif /* GDBSERVER_LINUX_LOW_H */ diff --git a/gdbserver/linux-ppc-low.cc b/gdbserver/linux-ppc-low.cc index 08824887003b..08608b2dcc38 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 (current_thread, features.wordsize); + ppc_hwcap2 = linux_get_hwcap2 (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 (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..0d01dffa64a4 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 (current_thread, 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..71ac61e9dfbd 100644 --- a/gdbserver/netbsd-low.cc +++ b/gdbserver/netbsd-low.cc @@ -581,10 +581,10 @@ 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 (const thread_info *thread, CORE_ADDR offset, unsigned char *myaddr, unsigned int len) { - pid_t pid = pid_of (current_thread); + pid_t pid = pid_of (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..506329251eaf 100644 --- a/gdbserver/netbsd-low.h +++ b/gdbserver/netbsd-low.h @@ -77,8 +77,8 @@ class netbsd_process_target : public process_stratum_target bool supports_read_auxv () override; - int read_auxv (CORE_ADDR offset, unsigned char *myaddr, - unsigned int len) override; + int read_auxv (const thread_info *thread, 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 c619206d5d2d..2d5cf6e8d8de 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 (current_thread, offset, readbuf, len); } /* Handle qXfer:exec-file:read. */ diff --git a/gdbserver/target.cc b/gdbserver/target.cc index adcfe6e7bcc7..7ee18bde8635 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 (const thread_info *thread, 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 6c536a307786..cd6b2193a228 100644 --- a/gdbserver/target.h +++ b/gdbserver/target.h @@ -175,8 +175,8 @@ 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, - unsigned int len); + virtual int read_auxv (const thread_info *thread, CORE_ADDR offset, + unsigned char *myaddr, unsigned int len); /* Returns true if GDB Z breakpoint type TYPE is supported, false otherwise. The type is coded as follows: