From: "Eric W. Biederman" <ebiederm@xmission.com> To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, Linus Torvalds <torvalds@linux-foundation.org>, Oleg Nesterov <oleg@redhat.com>, Al Viro <viro@ZenIV.linux.org.uk>, Kees Cook <keescook@chromium.org>, "Eric W. Biederman" <ebiederm@xmission.com>, Michael Ellerman <mpe@ellerman.id.au>, Benjamin Herrenschmidt <benh@kernel.crashing.org>, Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org Subject: [PATCH 07/20] signal/powerpc: On swapcontext failure force SIGSEGV Date: Wed, 20 Oct 2021 12:43:53 -0500 [thread overview] Message-ID: <20211020174406.17889-7-ebiederm@xmission.com> (raw) In-Reply-To: <87y26nmwkb.fsf@disp2133> If the register state may be partial and corrupted instead of calling do_exit, call force_sigsegv(SIGSEGV). Which properly kills the process with SIGSEGV and does not let any more userspace code execute, instead of just killing one thread of the process and potentially confusing everything. Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: linuxppc-dev@lists.ozlabs.org History-tree: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Fixes: 756f1ae8a44e ("PPC32: Rework signal code and add a swapcontext system call.") Fixes: 04879b04bf50 ("[PATCH] ppc64: VMX (Altivec) support & signal32 rework, from Ben Herrenschmidt") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> --- arch/powerpc/kernel/signal_32.c | 6 ++++-- arch/powerpc/kernel/signal_64.c | 9 ++++++--- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 0608581967f0..666f3da41232 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -1062,8 +1062,10 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx, * or if another thread unmaps the region containing the context. * We kill the task with a SIGSEGV in this situation. */ - if (do_setcontext(new_ctx, regs, 0)) - do_exit(SIGSEGV); + if (do_setcontext(new_ctx, regs, 0)) { + force_sigsegv(SIGSEGV); + return -EFAULT; + } set_thread_flag(TIF_RESTOREALL); return 0; diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 1831bba0582e..d8de622c9e4a 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -703,15 +703,18 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx, * We kill the task with a SIGSEGV in this situation. */ - if (__get_user_sigset(&set, &new_ctx->uc_sigmask)) - do_exit(SIGSEGV); + if (__get_user_sigset(&set, &new_ctx->uc_sigmask)) { + force_sigsegv(SIGSEGV); + return -EFAULT; + } set_current_blocked(&set); if (!user_read_access_begin(new_ctx, ctx_size)) return -EFAULT; if (__unsafe_restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext)) { user_read_access_end(); - do_exit(SIGSEGV); + force_sigsegv(SIGSEGV); + return -EFAULT; } user_read_access_end(); -- 2.20.1
WARNING: multiple messages have this Message-ID (diff)
From: "Eric W. Biederman" <ebiederm@xmission.com> To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, Kees Cook <keescook@chromium.org>, linuxppc-dev@lists.ozlabs.org, Oleg Nesterov <oleg@redhat.com>, Paul Mackerras <paulus@samba.org>, "Eric W. Biederman" <ebiederm@xmission.com>, Linus Torvalds <torvalds@linux-foundation.org>, Al Viro <viro@ZenIV.linux.org.uk> Subject: [PATCH 07/20] signal/powerpc: On swapcontext failure force SIGSEGV Date: Wed, 20 Oct 2021 12:43:53 -0500 [thread overview] Message-ID: <20211020174406.17889-7-ebiederm@xmission.com> (raw) In-Reply-To: <87y26nmwkb.fsf@disp2133> If the register state may be partial and corrupted instead of calling do_exit, call force_sigsegv(SIGSEGV). Which properly kills the process with SIGSEGV and does not let any more userspace code execute, instead of just killing one thread of the process and potentially confusing everything. Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: linuxppc-dev@lists.ozlabs.org History-tree: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Fixes: 756f1ae8a44e ("PPC32: Rework signal code and add a swapcontext system call.") Fixes: 04879b04bf50 ("[PATCH] ppc64: VMX (Altivec) support & signal32 rework, from Ben Herrenschmidt") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> --- arch/powerpc/kernel/signal_32.c | 6 ++++-- arch/powerpc/kernel/signal_64.c | 9 ++++++--- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 0608581967f0..666f3da41232 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -1062,8 +1062,10 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx, * or if another thread unmaps the region containing the context. * We kill the task with a SIGSEGV in this situation. */ - if (do_setcontext(new_ctx, regs, 0)) - do_exit(SIGSEGV); + if (do_setcontext(new_ctx, regs, 0)) { + force_sigsegv(SIGSEGV); + return -EFAULT; + } set_thread_flag(TIF_RESTOREALL); return 0; diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 1831bba0582e..d8de622c9e4a 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -703,15 +703,18 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx, * We kill the task with a SIGSEGV in this situation. */ - if (__get_user_sigset(&set, &new_ctx->uc_sigmask)) - do_exit(SIGSEGV); + if (__get_user_sigset(&set, &new_ctx->uc_sigmask)) { + force_sigsegv(SIGSEGV); + return -EFAULT; + } set_current_blocked(&set); if (!user_read_access_begin(new_ctx, ctx_size)) return -EFAULT; if (__unsafe_restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext)) { user_read_access_end(); - do_exit(SIGSEGV); + force_sigsegv(SIGSEGV); + return -EFAULT; } user_read_access_end(); -- 2.20.1
next prev parent reply other threads:[~2021-10-20 17:45 UTC|newest] Thread overview: 110+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-10-20 17:32 [PATCH 00/20] exit cleanups Eric W. Biederman 2021-10-20 17:32 ` [OpenRISC] " Eric W. Biederman 2021-10-20 17:32 ` Eric W. Biederman 2021-10-20 17:43 ` [PATCH 01/20] exit/doublefault: Remove apparently bogus comment about rewind_stack_do_exit Eric W. Biederman 2021-10-21 16:02 ` Kees Cook 2021-10-20 17:43 ` [PATCH 02/20] exit: Remove calls of do_exit after noreturn versions of die Eric W. Biederman 2021-10-20 17:43 ` [OpenRISC] " Eric W. Biederman 2021-10-21 16:02 ` Kees Cook 2021-10-21 16:02 ` [OpenRISC] " Kees Cook 2021-10-21 16:25 ` Eric W. Biederman 2021-10-21 16:25 ` [OpenRISC] " Eric W. Biederman 2021-10-20 17:43 ` [PATCH 03/20] reboot: Remove the unreachable panic after do_exit in reboot(2) Eric W. Biederman 2021-10-21 16:05 ` Kees Cook 2021-10-20 17:43 ` [PATCH 04/20] signal/sparc32: Remove unreachable do_exit in do_sparc_fault Eric W. Biederman 2021-10-21 16:05 ` Kees Cook 2021-10-20 17:43 ` [PATCH 05/20] signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT Eric W. Biederman 2021-10-21 16:06 ` Kees Cook 2021-10-24 4:24 ` Maciej W. Rozycki 2021-10-25 20:55 ` Eric W. Biederman 2021-10-24 15:27 ` Thomas Bogendoerfer 2021-10-20 17:43 ` [PATCH 06/20] signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL) Eric W. Biederman 2021-10-20 19:57 ` Linus Torvalds 2021-10-27 14:24 ` Rich Felker 2021-10-21 16:08 ` Kees Cook 2021-10-20 17:43 ` Eric W. Biederman [this message] 2021-10-20 17:43 ` [PATCH 07/20] signal/powerpc: On swapcontext failure force SIGSEGV Eric W. Biederman 2021-10-21 16:09 ` Kees Cook 2021-10-21 16:09 ` Kees Cook 2021-10-20 17:43 ` [PATCH 08/20] signal/sparc: In setup_tsb_params convert open coded BUG into BUG Eric W. Biederman 2021-10-21 16:12 ` Kees Cook 2021-10-20 17:43 ` [PATCH 09/20] signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON Eric W. Biederman 2021-10-21 16:15 ` Kees Cook 2021-11-12 15:40 ` Eric W. Biederman 2021-11-12 17:51 ` Brian Gerst 2021-11-12 19:57 ` Eric W. Biederman 2021-11-12 20:40 ` Linus Torvalds 2021-11-12 21:03 ` Eric W. Biederman 2021-11-12 21:23 ` Linus Torvalds 2021-11-12 21:24 ` Linus Torvalds 2021-11-12 21:37 ` [GIT PULL ] signal/vm86_32: Remove pointless test in BUG_ON Eric W. Biederman 2021-11-13 19:15 ` pr-tracker-bot 2021-11-12 21:43 ` [PATCH 09/20] signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON Eric W. Biederman 2021-10-20 17:43 ` [PATCH 10/20] signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved Eric W. Biederman 2021-10-21 16:16 ` Kees Cook 2021-10-21 17:02 ` Eric W. Biederman 2021-10-21 20:33 ` Kees Cook 2021-10-21 23:08 ` Andy Lutomirski 2021-10-24 16:06 ` Eric W. Biederman [not found] ` <875ytkygfj.fsf_-_@disp2133> 2021-10-25 21:12 ` [PATCH v2 10/32] " Linus Torvalds 2021-10-25 21:28 ` Eric W. Biederman 2021-10-25 22:25 ` Andy Lutomirski 2021-10-25 23:45 ` Linus Torvalds 2021-10-26 0:21 ` Andy Lutomirski 2021-10-20 17:43 ` [PATCH 11/20] signal/s390: Use force_sigsegv in default_trap_handler Eric W. Biederman 2021-10-21 16:17 ` Kees Cook 2021-10-26 9:38 ` Christian Borntraeger 2021-10-28 15:56 ` Eric W. Biederman 2021-10-29 19:32 ` Eric W. Biederman 2021-10-20 17:43 ` [PATCH 12/20] exit/kthread: Have kernel threads return instead of calling do_exit Eric W. Biederman 2021-10-21 11:12 ` Christoph Hellwig 2021-10-21 15:11 ` Eric W. Biederman 2021-10-21 16:21 ` Kees Cook 2021-10-20 17:43 ` [PATCH 13/20] signal: Implement force_fatal_sig Eric W. Biederman 2021-10-20 20:05 ` Linus Torvalds 2021-10-20 21:25 ` Eric W. Biederman 2021-10-25 22:41 ` Andy Lutomirski 2021-10-25 23:15 ` Linus Torvalds 2021-10-26 4:45 ` Eric W. Biederman 2021-10-26 4:57 ` Eric W. Biederman 2021-10-26 16:15 ` Linus Torvalds 2021-10-28 16:33 ` Eric W. Biederman 2021-10-21 16:24 ` Kees Cook 2021-10-21 16:33 ` Eric W. Biederman 2021-10-21 16:39 ` Kees Cook 2021-10-20 17:44 ` [PATCH 14/20] exit/syscall_user_dispatch: Send ordinary signals on failure Eric W. Biederman 2021-10-21 16:25 ` Kees Cook 2021-10-21 16:37 ` Eric W. Biederman 2021-10-21 16:40 ` Kees Cook 2021-10-21 17:05 ` Eric W. Biederman 2021-10-25 22:32 ` Andy Lutomirski 2021-10-21 16:35 ` Gabriel Krisman Bertazi 2021-10-20 17:44 ` [PATCH 15/20] signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails Eric W. Biederman 2021-10-21 16:34 ` Kees Cook 2021-10-21 16:56 ` Eric W. Biederman 2021-10-20 17:44 ` [PATCH 16/20] signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig Eric W. Biederman 2021-10-21 16:34 ` Kees Cook 2021-10-20 17:44 ` [PATCH 17/20] signal/x86: In emulate_vsyscall force a signal instead of calling do_exit Eric W. Biederman 2021-10-21 16:36 ` Kees Cook 2021-10-20 17:44 ` [PATCH 18/20] exit/rtl8723bs: Replace the macro thread_exit with a simple return 0 Eric W. Biederman 2021-10-21 7:06 ` Greg KH 2021-10-21 15:06 ` Eric W. Biederman 2021-10-21 16:37 ` Kees Cook 2021-10-20 17:44 ` [PATCH 19/20] exit/rtl8712: " Eric W. Biederman 2021-10-21 7:07 ` Greg KH 2021-10-21 16:37 ` Kees Cook 2021-10-20 17:44 ` [PATCH 20/20] exit/r8188eu: " Eric W. Biederman 2021-10-21 7:07 ` Greg KH 2021-10-21 16:37 ` Kees Cook 2021-10-20 21:51 ` [PATCH 21/20] signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV) Eric W. Biederman 2021-10-20 21:51 ` [OpenRISC] " Eric W. Biederman 2021-10-20 21:51 ` Eric W. Biederman 2021-10-21 8:09 ` Geert Uytterhoeven 2021-10-21 8:09 ` [OpenRISC] " Geert Uytterhoeven 2021-10-21 8:09 ` Geert Uytterhoeven 2021-10-21 13:33 ` Eric W. Biederman 2021-10-21 13:33 ` [OpenRISC] " Eric W. Biederman 2021-10-21 13:33 ` Eric W. Biederman 2021-10-21 8:32 ` Philippe Mathieu-Daudé 2021-10-21 8:32 ` [OpenRISC] " Philippe =?unknown-8bit?q?Mathieu-Daud=C3=A9?= 2021-10-21 8:32 ` Philippe Mathieu-Daudé
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