From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Konovalov Subject: Re: [PATCH v11 10/14] tracing, arm64: untag user pointers in seq_print_user_ip Date: Mon, 18 Mar 2019 14:11:48 +0100 Message-ID: References: <355e7c0dadaa2bb79d22e0b7aac7e4efc1114d49.1552679409.git.andreyknvl@google.com> <20190315161414.4b31fb03@gandalf.local.home> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20190315161414.4b31fb03@gandalf.local.home> Sender: linux-kernel-owner@vger.kernel.org To: Steven Rostedt Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , Eric Dumazet , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo List-Id: linux-arch.vger.kernel.org On Fri, Mar 15, 2019 at 9:14 PM Steven Rostedt wrote: > > On Fri, 15 Mar 2019 20:51:34 +0100 > Andrey Konovalov wrote: > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > seq_print_user_ip() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > kernel/trace/trace_output.c | 5 +++-- > > p | 45 +++++++++++++++++++++++++++++++++++++ > > 2 files changed, 48 insertions(+), 2 deletions(-) > > create mode 100644 p > > > > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c > > index 54373d93e251..6376bee93c84 100644 > > --- a/kernel/trace/trace_output.c > > +++ b/kernel/trace/trace_output.c > > @@ -370,6 +370,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, > > { > > struct file *file = NULL; > > unsigned long vmstart = 0; > > + unsigned long untagged_ip = untagged_addr(ip); > > int ret = 1; > > > > if (s->full) > > @@ -379,7 +380,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, > > const struct vm_area_struct *vma; > > > > down_read(&mm->mmap_sem); > > - vma = find_vma(mm, ip); > > + vma = find_vma(mm, untagged_ip); > > if (vma) { > > file = vma->vm_file; > > vmstart = vma->vm_start; > > @@ -388,7 +389,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, > > ret = trace_seq_path(s, &file->f_path); > > if (ret) > > trace_seq_printf(s, "[+0x%lx]", > > - ip - vmstart); > > + untagged_ip - vmstart); > > } > > up_read(&mm->mmap_sem); > > } > > diff --git a/p b/p > > new file mode 100644 > > index 000000000000..9d6fa5386e55 > > --- /dev/null > > +++ b/p > > @@ -0,0 +1,45 @@ > > +commit 1fa6fadf644859e8a6a8ecce258444b49be8c7ee > > +Author: Andrey Konovalov > > +Date: Mon Mar 4 17:20:32 2019 +0100 > > + > > + kasan: fix coccinelle warnings in kasan_p*_table > > + > > + kasan_p4d_table, kasan_pmd_table and kasan_pud_table are declared as > > + returning bool, but return 0 instead of false, which produces a coccinelle > > + warning. Fix it. > > + > > + Fixes: 0207df4fa1a8 ("kernel/memremap, kasan: make ZONE_DEVICE with work with KASAN") > > + Reported-by: kbuild test robot > > + Signed-off-by: Andrey Konovalov > > Did you mean to append this commit to this patch? No, did it by mistake. Will remove in v12, thanks for noticing! > > -- Steve > > > + > > +diff --git a/mm/kasan/init.c b/mm/kasan/init.c > > +index 45a1b5e38e1e..fcaa1ca03175 100644 > > +--- a/mm/kasan/init.c > > ++++ b/mm/kasan/init.c > > +@@ -42,7 +42,7 @@ static inline bool kasan_p4d_table(pgd_t pgd) > > + #else > > + static inline bool kasan_p4d_table(pgd_t pgd) > > + { > > +- return 0; > > ++ return false; > > + } > > + #endif > > + #if CONFIG_PGTABLE_LEVELS > 3 > > +@@ -54,7 +54,7 @@ static inline bool kasan_pud_table(p4d_t p4d) > > + #else > > + static inline bool kasan_pud_table(p4d_t p4d) > > + { > > +- return 0; > > ++ return false; > > + } > > + #endif > > + #if CONFIG_PGTABLE_LEVELS > 2 > > +@@ -66,7 +66,7 @@ static inline bool kasan_pmd_table(pud_t pud) > > + #else > > + static inline bool kasan_pmd_table(pud_t pud) > > + { > > +- return 0; > > ++ return false; > > + } > > + #endif > > + pte_t kasan_early_shadow_pte[PTRS_PER_PTE] __page_aligned_bss; > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-f194.google.com ([209.85.215.194]:35070 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726704AbfCRNMB (ORCPT ); Mon, 18 Mar 2019 09:12:01 -0400 Received: by mail-pg1-f194.google.com with SMTP id g8so697184pgf.2 for ; Mon, 18 Mar 2019 06:12:01 -0700 (PDT) MIME-Version: 1.0 References: <355e7c0dadaa2bb79d22e0b7aac7e4efc1114d49.1552679409.git.andreyknvl@google.com> <20190315161414.4b31fb03@gandalf.local.home> In-Reply-To: <20190315161414.4b31fb03@gandalf.local.home> From: Andrey Konovalov Date: Mon, 18 Mar 2019 14:11:48 +0100 Message-ID: Subject: Re: [PATCH v11 10/14] tracing, arm64: untag user pointers in seq_print_user_ip Content-Type: text/plain; charset="UTF-8" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Steven Rostedt Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , Eric Dumazet , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , Linux Memory Management List , linux-arch , netdev , bpf@vger.kernel.org, "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Message-ID: <20190318131148.PEGxU5rorhLTsNpByp3CPswQeE4Nv_QktwOxOutHmIE@z> On Fri, Mar 15, 2019 at 9:14 PM Steven Rostedt wrote: > > On Fri, 15 Mar 2019 20:51:34 +0100 > Andrey Konovalov wrote: > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > seq_print_user_ip() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > kernel/trace/trace_output.c | 5 +++-- > > p | 45 +++++++++++++++++++++++++++++++++++++ > > 2 files changed, 48 insertions(+), 2 deletions(-) > > create mode 100644 p > > > > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c > > index 54373d93e251..6376bee93c84 100644 > > --- a/kernel/trace/trace_output.c > > +++ b/kernel/trace/trace_output.c > > @@ -370,6 +370,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, > > { > > struct file *file = NULL; > > unsigned long vmstart = 0; > > + unsigned long untagged_ip = untagged_addr(ip); > > int ret = 1; > > > > if (s->full) > > @@ -379,7 +380,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, > > const struct vm_area_struct *vma; > > > > down_read(&mm->mmap_sem); > > - vma = find_vma(mm, ip); > > + vma = find_vma(mm, untagged_ip); > > if (vma) { > > file = vma->vm_file; > > vmstart = vma->vm_start; > > @@ -388,7 +389,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, > > ret = trace_seq_path(s, &file->f_path); > > if (ret) > > trace_seq_printf(s, "[+0x%lx]", > > - ip - vmstart); > > + untagged_ip - vmstart); > > } > > up_read(&mm->mmap_sem); > > } > > diff --git a/p b/p > > new file mode 100644 > > index 000000000000..9d6fa5386e55 > > --- /dev/null > > +++ b/p > > @@ -0,0 +1,45 @@ > > +commit 1fa6fadf644859e8a6a8ecce258444b49be8c7ee > > +Author: Andrey Konovalov > > +Date: Mon Mar 4 17:20:32 2019 +0100 > > + > > + kasan: fix coccinelle warnings in kasan_p*_table > > + > > + kasan_p4d_table, kasan_pmd_table and kasan_pud_table are declared as > > + returning bool, but return 0 instead of false, which produces a coccinelle > > + warning. Fix it. > > + > > + Fixes: 0207df4fa1a8 ("kernel/memremap, kasan: make ZONE_DEVICE with work with KASAN") > > + Reported-by: kbuild test robot > > + Signed-off-by: Andrey Konovalov > > Did you mean to append this commit to this patch? No, did it by mistake. Will remove in v12, thanks for noticing! > > -- Steve > > > + > > +diff --git a/mm/kasan/init.c b/mm/kasan/init.c > > +index 45a1b5e38e1e..fcaa1ca03175 100644 > > +--- a/mm/kasan/init.c > > ++++ b/mm/kasan/init.c > > +@@ -42,7 +42,7 @@ static inline bool kasan_p4d_table(pgd_t pgd) > > + #else > > + static inline bool kasan_p4d_table(pgd_t pgd) > > + { > > +- return 0; > > ++ return false; > > + } > > + #endif > > + #if CONFIG_PGTABLE_LEVELS > 3 > > +@@ -54,7 +54,7 @@ static inline bool kasan_pud_table(p4d_t p4d) > > + #else > > + static inline bool kasan_pud_table(p4d_t p4d) > > + { > > +- return 0; > > ++ return false; > > + } > > + #endif > > + #if CONFIG_PGTABLE_LEVELS > 2 > > +@@ -66,7 +66,7 @@ static inline bool kasan_pmd_table(pud_t pud) > > + #else > > + static inline bool kasan_pmd_table(pud_t pud) > > + { > > +- return 0; > > ++ return false; > > + } > > + #endif > > + pte_t kasan_early_shadow_pte[PTRS_PER_PTE] __page_aligned_bss; >