From 48280042f2c6e3ac2cfb1d8b752ab4a7e0baea24 Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Wed, 10 Aug 2022 23:19:09 +0100 Subject: x86/fpu/xstate: Fix XSTATE_WARN_ON() to emit relevant diagnostics "XSAVE consistency problem" has been reported under Xen, but that's the extent of my divination skills. Modify XSTATE_WARN_ON() to force the caller to provide relevant diagnostic information, and modify each caller suitably. For check_xstate_against_struct(), this removes a double WARN() where one will do perfectly fine. CC stable as this has been wonky debugging for 7 years and it is good to have there too. Signed-off-by: Andrew Cooper Signed-off-by: Borislav Petkov Cc: Link: https://lore.kernel.org/r/20220810221909.12768-1-andrew.cooper3@citrix.com --- arch/x86/kernel/fpu/xstate.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 59e543b95a3c..c2dde46a538e 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -440,8 +440,8 @@ static void __init __xstate_dump_leaves(void) } } -#define XSTATE_WARN_ON(x) do { \ - if (WARN_ONCE(x, "XSAVE consistency problem, dumping leaves")) { \ +#define XSTATE_WARN_ON(x, fmt, ...) do { \ + if (WARN_ONCE(x, "XSAVE consistency problem: " fmt, ##__VA_ARGS__)) { \ __xstate_dump_leaves(); \ } \ } while (0) @@ -554,8 +554,7 @@ static bool __init check_xstate_against_struct(int nr) (nr >= XFEATURE_MAX) || (nr == XFEATURE_PT_UNIMPLEMENTED_SO_FAR) || ((nr >= XFEATURE_RSRVD_COMP_11) && (nr <= XFEATURE_RSRVD_COMP_16))) { - WARN_ONCE(1, "no structure for xstate: %d\n", nr); - XSTATE_WARN_ON(1); + XSTATE_WARN_ON(1, "No structure for xstate: %d\n", nr); return false; } return true; @@ -598,12 +597,13 @@ static bool __init paranoid_xstate_size_valid(unsigned int kernel_size) * XSAVES. */ if (!xsaves && xfeature_is_supervisor(i)) { - XSTATE_WARN_ON(1); + XSTATE_WARN_ON(1, "Got supervisor feature %d, but XSAVES not advertised\n", i); return false; } } size = xstate_calculate_size(fpu_kernel_cfg.max_features, compacted); - XSTATE_WARN_ON(size != kernel_size); + XSTATE_WARN_ON(size != kernel_size, + "size %u != kernel_size %u\n", size, kernel_size); return size == kernel_size; } -- cgit v1.2.3 From 6a877d2450ace4f27c012519e5a1ae818f931983 Mon Sep 17 00:00:00 2001 From: Kyle Huey Date: Tue, 15 Nov 2022 15:09:27 -0800 Subject: x86/fpu: Take task_struct* in copy_sigframe_from_user_to_xstate() This will allow copy_sigframe_from_user_to_xstate() to grab the address of thread_struct's pkru value in a later patch. Signed-off-by: Kyle Huey Signed-off-by: Dave Hansen Link: https://lore.kernel.org/all/20221115230932.7126-2-khuey%40kylehuey.com --- arch/x86/kernel/fpu/signal.c | 2 +- arch/x86/kernel/fpu/xstate.c | 4 ++-- arch/x86/kernel/fpu/xstate.h | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index 91d4b6de58ab..558076dbde5b 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -396,7 +396,7 @@ static bool __fpu_restore_sig(void __user *buf, void __user *buf_fx, fpregs = &fpu->fpstate->regs; if (use_xsave() && !fx_only) { - if (copy_sigframe_from_user_to_xstate(fpu->fpstate, buf_fx)) + if (copy_sigframe_from_user_to_xstate(tsk, buf_fx)) return false; } else { if (__copy_from_user(&fpregs->fxsave, buf_fx, diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index c2dde46a538e..c88c60bac3ae 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1278,10 +1278,10 @@ int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf) * XSAVE[S] format and copy to the target thread. This is called from the * sigreturn() and rt_sigreturn() system calls. */ -int copy_sigframe_from_user_to_xstate(struct fpstate *fpstate, +int copy_sigframe_from_user_to_xstate(struct task_struct *tsk, const void __user *ubuf) { - return copy_uabi_to_xstate(fpstate, NULL, ubuf); + return copy_uabi_to_xstate(tsk->thread.fpu.fpstate, NULL, ubuf); } static bool validate_independent_components(u64 mask) diff --git a/arch/x86/kernel/fpu/xstate.h b/arch/x86/kernel/fpu/xstate.h index 5ad47031383b..f08ee2722e74 100644 --- a/arch/x86/kernel/fpu/xstate.h +++ b/arch/x86/kernel/fpu/xstate.h @@ -47,7 +47,7 @@ extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate, extern void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk, enum xstate_copy_mode mode); extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf); -extern int copy_sigframe_from_user_to_xstate(struct fpstate *fpstate, const void __user *ubuf); +extern int copy_sigframe_from_user_to_xstate(struct task_struct *tsk, const void __user *ubuf); extern void fpu__init_cpu_xstate(void); -- cgit v1.2.3 From 1c813ce0305571e1b2e4cc4acca451da9e6ad18f Mon Sep 17 00:00:00 2001 From: Kyle Huey Date: Tue, 15 Nov 2022 15:09:28 -0800 Subject: x86/fpu: Add a pkru argument to copy_uabi_from_kernel_to_xstate(). Both KVM (through KVM_SET_XSTATE) and ptrace (through PTRACE_SETREGSET with NT_X86_XSTATE) ultimately call copy_uabi_from_kernel_to_xstate(), but the canonical locations for the current PKRU value for KVM guests and processes in a ptrace stop are different (in the kvm_vcpu_arch and the thread_state structs respectively). In preparation for eventually handling PKRU in copy_uabi_to_xstate, pass in a pointer to the PKRU location. Signed-off-by: Kyle Huey Signed-off-by: Dave Hansen Link: https://lore.kernel.org/all/20221115230932.7126-3-khuey%40kylehuey.com --- arch/x86/kernel/fpu/core.c | 2 +- arch/x86/kernel/fpu/regset.c | 2 +- arch/x86/kernel/fpu/xstate.c | 2 +- arch/x86/kernel/fpu/xstate.h | 2 +- 4 files changed, 4 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 3b28c5b25e12..550157686323 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -406,7 +406,7 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, if (ustate->xsave.header.xfeatures & ~xcr0) return -EINVAL; - ret = copy_uabi_from_kernel_to_xstate(kstate, ustate); + ret = copy_uabi_from_kernel_to_xstate(kstate, ustate, vpkru); if (ret) return ret; diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c index 75ffaef8c299..6d056b68f4ed 100644 --- a/arch/x86/kernel/fpu/regset.c +++ b/arch/x86/kernel/fpu/regset.c @@ -167,7 +167,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset, } fpu_force_restore(fpu); - ret = copy_uabi_from_kernel_to_xstate(fpu->fpstate, kbuf ?: tmpbuf); + ret = copy_uabi_from_kernel_to_xstate(fpu->fpstate, kbuf ?: tmpbuf, &target->thread.pkru); out: vfree(tmpbuf); diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index c88c60bac3ae..d6f414af00cb 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1268,7 +1268,7 @@ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, * Convert from a ptrace standard-format kernel buffer to kernel XSAVE[S] * format and copy to the target thread. Used by ptrace and KVM. */ -int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf) +int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru) { return copy_uabi_to_xstate(fpstate, kbuf, NULL); } diff --git a/arch/x86/kernel/fpu/xstate.h b/arch/x86/kernel/fpu/xstate.h index f08ee2722e74..a4ecb04d8d64 100644 --- a/arch/x86/kernel/fpu/xstate.h +++ b/arch/x86/kernel/fpu/xstate.h @@ -46,7 +46,7 @@ extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate, u32 pkru_val, enum xstate_copy_mode copy_mode); extern void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk, enum xstate_copy_mode mode); -extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf); +extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru); extern int copy_sigframe_from_user_to_xstate(struct task_struct *tsk, const void __user *ubuf); -- cgit v1.2.3 From 2c87767c35ee9744f666ccec869d5fe742c3de0a Mon Sep 17 00:00:00 2001 From: Kyle Huey Date: Tue, 15 Nov 2022 15:09:29 -0800 Subject: x86/fpu: Add a pkru argument to copy_uabi_to_xstate() In preparation for moving PKRU handling code out of fpu_copy_uabi_to_guest_fpstate() and into copy_uabi_to_xstate(), add an argument that copy_uabi_from_kernel_to_xstate() can use to pass the canonical location of the PKRU value. For copy_sigframe_from_user_to_xstate() the kernel will actually restore the PKRU value from the fpstate, but pass in the thread_struct's pkru location anyways for consistency. Signed-off-by: Kyle Huey Signed-off-by: Dave Hansen Link: https://lore.kernel.org/all/20221115230932.7126-4-khuey%40kylehuey.com --- arch/x86/kernel/fpu/xstate.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index d6f414af00cb..d657c8b1fb08 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1200,8 +1200,18 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size, } +/** + * copy_uabi_to_xstate - Copy a UABI format buffer to the kernel xstate + * @fpstate: The fpstate buffer to copy to + * @kbuf: The UABI format buffer, if it comes from the kernel + * @ubuf: The UABI format buffer, if it comes from userspace + * @pkru: unused + * + * Converts from the UABI format into the kernel internal hardware + * dependent format. + */ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, - const void __user *ubuf) + const void __user *ubuf, u32 *pkru) { struct xregs_state *xsave = &fpstate->regs.xsave; unsigned int offset, size; @@ -1270,7 +1280,7 @@ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, */ int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru) { - return copy_uabi_to_xstate(fpstate, kbuf, NULL); + return copy_uabi_to_xstate(fpstate, kbuf, NULL, pkru); } /* @@ -1281,7 +1291,7 @@ int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u int copy_sigframe_from_user_to_xstate(struct task_struct *tsk, const void __user *ubuf) { - return copy_uabi_to_xstate(tsk->thread.fpu.fpstate, NULL, ubuf); + return copy_uabi_to_xstate(tsk->thread.fpu.fpstate, NULL, ubuf, &tsk->thread.pkru); } static bool validate_independent_components(u64 mask) -- cgit v1.2.3 From 4a804c4f8356393d6b5eff7600f07615d7869c13 Mon Sep 17 00:00:00 2001 From: Kyle Huey Date: Tue, 15 Nov 2022 15:09:30 -0800 Subject: x86/fpu: Allow PKRU to be (once again) written by ptrace. Move KVM's PKRU handling code in fpu_copy_uabi_to_guest_fpstate() to copy_uabi_to_xstate() so that it is shared with other APIs that write the XSTATE such as PTRACE_SETREGSET with NT_X86_XSTATE. This restores the pre-5.14 behavior of ptrace. The regression can be seen by running gdb and executing `p $pkru`, `set $pkru = 42`, and `p $pkru`. On affected kernels (5.14+) the write to the PKRU register (which gdb performs through ptrace) is ignored. [ dhansen: removed stable@ tag for now. The ABI was broken for long enough that this is not urgent material. Let's let it stew in tip for a few weeks before it's submitted to stable because there are so many ABIs potentially affected. ] Fixes: e84ba47e313d ("x86/fpu: Hook up PKRU into ptrace()") Signed-off-by: Kyle Huey Signed-off-by: Dave Hansen Link: https://lore.kernel.org/all/20221115230932.7126-5-khuey%40kylehuey.com --- arch/x86/kernel/fpu/core.c | 13 +------------ arch/x86/kernel/fpu/xstate.c | 21 ++++++++++++++++++++- 2 files changed, 21 insertions(+), 13 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 550157686323..46b935bc87c8 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -391,8 +391,6 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, { struct fpstate *kstate = gfpu->fpstate; const union fpregs_state *ustate = buf; - struct pkru_state *xpkru; - int ret; if (!cpu_feature_enabled(X86_FEATURE_XSAVE)) { if (ustate->xsave.header.xfeatures & ~XFEATURE_MASK_FPSSE) @@ -406,16 +404,7 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, if (ustate->xsave.header.xfeatures & ~xcr0) return -EINVAL; - ret = copy_uabi_from_kernel_to_xstate(kstate, ustate, vpkru); - if (ret) - return ret; - - /* Retrieve PKRU if not in init state */ - if (kstate->regs.xsave.header.xfeatures & XFEATURE_MASK_PKRU) { - xpkru = get_xsave_addr(&kstate->regs.xsave, XFEATURE_PKRU); - *vpkru = xpkru->pkru; - } - return 0; + return copy_uabi_from_kernel_to_xstate(kstate, ustate, vpkru); } EXPORT_SYMBOL_GPL(fpu_copy_uabi_to_guest_fpstate); #endif /* CONFIG_KVM */ diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index d657c8b1fb08..a8cf604d8a25 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1205,10 +1205,22 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size, * @fpstate: The fpstate buffer to copy to * @kbuf: The UABI format buffer, if it comes from the kernel * @ubuf: The UABI format buffer, if it comes from userspace - * @pkru: unused + * @pkru: The location to write the PKRU value to * * Converts from the UABI format into the kernel internal hardware * dependent format. + * + * This function ultimately has three different callers with distinct PKRU + * behavior. + * 1. When called from sigreturn the PKRU register will be restored from + * @fpstate via an XRSTOR. Correctly copying the UABI format buffer to + * @fpstate is sufficient to cover this case, but the caller will also + * pass a pointer to the thread_struct's pkru field in @pkru and updating + * it is harmless. + * 2. When called from ptrace the PKRU register will be restored from the + * thread_struct's pkru field. A pointer to that is passed in @pkru. + * 3. When called from KVM the PKRU register will be restored from the vcpu's + * pkru field. A pointer to that is passed in @pkru. */ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, const void __user *ubuf, u32 *pkru) @@ -1260,6 +1272,13 @@ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, } } + if (hdr.xfeatures & XFEATURE_MASK_PKRU) { + struct pkru_state *xpkru; + + xpkru = __raw_xsave_addr(xsave, XFEATURE_PKRU); + *pkru = xpkru->pkru; + } + /* * The state that came in from userspace was user-state only. * Mask all the user states out of 'xfeatures': -- cgit v1.2.3 From d7e5aceace514a2b1b3ca3dc44f93f1704766ca7 Mon Sep 17 00:00:00 2001 From: Kyle Huey Date: Tue, 15 Nov 2022 15:09:31 -0800 Subject: x86/fpu: Emulate XRSTOR's behavior if the xfeatures PKRU bit is not set The hardware XRSTOR instruction resets the PKRU register to its hardware init value (namely 0) if the PKRU bit is not set in the xfeatures mask. Emulating that here restores the pre-5.14 behavior for PTRACE_SET_REGSET with NT_X86_XSTATE, and makes sigreturn (which still uses XRSTOR) and ptrace behave identically. KVM has never used XRSTOR and never had this behavior, so KVM opts-out of this emulation by passing a NULL pkru pointer to copy_uabi_to_xstate(). Fixes: e84ba47e313d ("x86/fpu: Hook up PKRU into ptrace()") Signed-off-by: Kyle Huey Signed-off-by: Dave Hansen Link: https://lore.kernel.org/all/20221115230932.7126-6-khuey%40kylehuey.com --- arch/x86/kernel/fpu/core.c | 8 ++++++++ arch/x86/kernel/fpu/xstate.c | 15 ++++++++++++++- 2 files changed, 22 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 46b935bc87c8..8d0f6019c21d 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -404,6 +404,14 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, if (ustate->xsave.header.xfeatures & ~xcr0) return -EINVAL; + /* + * Nullify @vpkru to preserve its current value if PKRU's bit isn't set + * in the header. KVM's odd ABI is to leave PKRU untouched in this + * case (all other components are eventually re-initialized). + */ + if (!(ustate->xsave.header.xfeatures & XFEATURE_MASK_PKRU)) + vpkru = NULL; + return copy_uabi_from_kernel_to_xstate(kstate, ustate, vpkru); } EXPORT_SYMBOL_GPL(fpu_copy_uabi_to_guest_fpstate); diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index a8cf604d8a25..714166cc25f2 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1219,8 +1219,14 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size, * it is harmless. * 2. When called from ptrace the PKRU register will be restored from the * thread_struct's pkru field. A pointer to that is passed in @pkru. + * The kernel will restore it manually, so the XRSTOR behavior that resets + * the PKRU register to the hardware init value (0) if the corresponding + * xfeatures bit is not set is emulated here. * 3. When called from KVM the PKRU register will be restored from the vcpu's - * pkru field. A pointer to that is passed in @pkru. + * pkru field. A pointer to that is passed in @pkru. KVM hasn't used + * XRSTOR and hasn't had the PKRU resetting behavior described above. To + * preserve that KVM behavior, it passes NULL for @pkru if the xfeatures + * bit is not set. */ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, const void __user *ubuf, u32 *pkru) @@ -1277,6 +1283,13 @@ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, xpkru = __raw_xsave_addr(xsave, XFEATURE_PKRU); *pkru = xpkru->pkru; + } else { + /* + * KVM may pass NULL here to indicate that it does not need + * PKRU updated. + */ + if (pkru) + *pkru = 0; } /* -- cgit v1.2.3 From 55228db2697c09abddcb9487c3d9fa5854a932cd Mon Sep 17 00:00:00 2001 From: YingChi Long Date: Fri, 18 Nov 2022 08:55:35 +0800 Subject: x86/fpu: Use _Alignof to avoid undefined behavior in TYPE_ALIGN WG14 N2350 specifies that it is an undefined behavior to have type definitions within offsetof", see https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2350.htm This specification is also part of C23. Therefore, replace the TYPE_ALIGN macro with the _Alignof builtin to avoid undefined behavior. (_Alignof itself is C11 and the kernel is built with -gnu11). ISO C11 _Alignof is subtly different from the GNU C extension __alignof__. Latter is the preferred alignment and _Alignof the minimal alignment. For long long on x86 these are 8 and 4 respectively. The macro TYPE_ALIGN's behavior matches _Alignof rather than __alignof__. [ bp: Massage commit message. ] Signed-off-by: YingChi Long Signed-off-by: Borislav Petkov Reviewed-by: Nick Desaulniers Link: https://lore.kernel.org/r/20220925153151.2467884-1-me@inclyc.cn --- arch/x86/kernel/fpu/init.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 8946f89761cc..851eb13edc01 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -133,9 +133,6 @@ static void __init fpu__init_system_generic(void) fpu__init_system_mxcsr(); } -/* Get alignment of the TYPE. */ -#define TYPE_ALIGN(TYPE) offsetof(struct { char x; TYPE test; }, test) - /* * Enforce that 'MEMBER' is the last field of 'TYPE'. * @@ -143,8 +140,8 @@ static void __init fpu__init_system_generic(void) * because that's how C aligns structs. */ #define CHECK_MEMBER_AT_END_OF(TYPE, MEMBER) \ - BUILD_BUG_ON(sizeof(TYPE) != ALIGN(offsetofend(TYPE, MEMBER), \ - TYPE_ALIGN(TYPE))) + BUILD_BUG_ON(sizeof(TYPE) != \ + ALIGN(offsetofend(TYPE, MEMBER), _Alignof(TYPE))) /* * We append the 'struct fpu' to the task_struct: -- cgit v1.2.3