diff --git a/linux54-tkg/PKGBUILD b/linux54-tkg/PKGBUILD index 882d525..7c24d2b 100644 --- a/linux54-tkg/PKGBUILD +++ b/linux54-tkg/PKGBUILD @@ -89,7 +89,7 @@ pkgname=("${pkgbase}" "${pkgbase}-headers") _basekernel=5.4 _sub=40 pkgver="${_basekernel}"."${_sub}" -pkgrel=55 +pkgrel=56 pkgdesc='Linux-tkg' arch=('x86_64') # no i686 in here url="http://www.kernel.org/" @@ -131,7 +131,7 @@ sha256sums=('bf338980b1670bca287f9994b7441c2361907635879169c64ae78364efc5f491' '66a03c246037451a77b4d448565b1d7e9368270c7d02872fbd0b5d024ed0a997' '31dc68e84aecfb7d069efb1305049122c65694676be8b955634abcf0675922a2' 'd02bf5ca08fd610394b9d3a0c3b176d74af206f897dee826e5cbaec97bb4a4aa' - '55db7c30c6d5e7d88cf38a4c757e447faf11a7440afbc081c3da12757073cca7' + '10b3cb5c160abe6609ddb472c4012f1e473154ab8edaa680418d9615548a303c' '7058e57fd68367b029adc77f2a82928f1433daaf02c8c279cb2d13556c8804d7' 'c605f638d74c61861ebdc36ebd4cb8b6475eae2f6273e1ccb2bbb3e10a2ec3fe' 'bc69d6e5ee8172b0242c8fa72d13cfe2b8d2b6601468836908a7dfe8b78a3bbb' diff --git a/linux54-tkg/linux54-tkg-patches/0003-glitched-base.patch b/linux54-tkg/linux54-tkg-patches/0003-glitched-base.patch index 36cfd14..3a971ea 100644 --- a/linux54-tkg/linux54-tkg-patches/0003-glitched-base.patch +++ b/linux54-tkg/linux54-tkg-patches/0003-glitched-base.patch @@ -5197,3 +5197,129 @@ index a2adf95b3f9c..e804d9f7583a 100644 int force_page_cache_readahead(struct address_space *mapping, struct file *filp, pgoff_t offset, unsigned long nr_to_read); + +rom f670269a42bfdd2c83a1118cc3d1b475547eac22 Mon Sep 17 00:00:00 2001 +From: Borislav Petkov +Date: Wed, 22 Apr 2020 18:11:30 +0200 +Subject: x86: Fix early boot crash on gcc-10, next try + +... or the odyssey of trying to disable the stack protector for the +function which generates the stack canary value. + +The whole story started with Sergei reporting a boot crash with a kernel +built with gcc-10: + + Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary + CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 + Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 + Call Trace: + dump_stack + panic + ? start_secondary + __stack_chk_fail + start_secondary + secondary_startup_64 + -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary + +This happens because gcc-10 tail-call optimizes the last function call +in start_secondary() - cpu_startup_entry() - and thus emits a stack +canary check which fails because the canary value changes after the +boot_init_stack_canary() call. + +To fix that, the initial attempt was to mark the one function which +generates the stack canary with: + + __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) + +however, using the optimize attribute doesn't work cumulatively +as the attribute does not add to but rather replaces previously +supplied optimization options - roughly all -fxxx options. + +The key one among them being -fno-omit-frame-pointer and thus leading to +not present frame pointer - frame pointer which the kernel needs. + +The next attempt to prevent compilers from tail-call optimizing +the last function call cpu_startup_entry(), shy of carving out +start_secondary() into a separate compilation unit and building it with + -fno-stack-protector, is this one. + +The current solution is short and sweet, and reportedly, is supported by +both compilers so let's see how far we'll get this time. + +Reported-by: Sergei Trofimovich +Signed-off-by: Borislav Petkov +Reviewed-by: Nick Desaulniers +Reviewed-by: Kees Cook +Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org +--- + arch/x86/include/asm/stackprotector.h | 7 ++++++- + arch/x86/kernel/smpboot.c | 8 ++++++++ + arch/x86/xen/smp_pv.c | 1 + + include/linux/compiler.h | 6 ++++++ + 4 files changed, 21 insertions(+), 1 deletion(-) + +diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h +index 91e29b6a86a5..9804a7957f4e 100644 +--- a/arch/x86/include/asm/stackprotector.h ++++ b/arch/x86/include/asm/stackprotector.h +@@ -55,8 +55,13 @@ + /* + * Initialize the stackprotector canary value. + * +- * NOTE: this must only be called from functions that never return, ++ * NOTE: this must only be called from functions that never return + * and it must always be inlined. ++ * ++ * In addition, it should be called from a compilation unit for which ++ * stack protector is disabled. Alternatively, the caller should not end ++ * with a function call which gets tail-call optimized as that would ++ * lead to checking a modified canary value. + */ + static __always_inline void boot_init_stack_canary(void) + { +diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c +index fe3ab9632f3b..4f275ac7830b 100644 +--- a/arch/x86/kernel/smpboot.c ++++ b/arch/x86/kernel/smpboot.c +@@ -266,6 +266,14 @@ static void notrace start_secondary(void *unused) + + wmb(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ ++ /* ++ * Prevent tail call to cpu_startup_entry() because the stack protector ++ * guard has been changed a couple of function calls up, in ++ * boot_init_stack_canary() and must not be checked before tail calling ++ * another function. ++ */ ++ prevent_tail_call_optimization(); + } + + /** +diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c +index 8fb8a50a28b4..f2adb63b2d7c 100644 +--- a/arch/x86/xen/smp_pv.c ++++ b/arch/x86/xen/smp_pv.c +@@ -93,6 +93,7 @@ asmlinkage __visible void cpu_bringup_and_idle(void) + cpu_bringup(); + boot_init_stack_canary(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ prevent_tail_call_optimization(); + } + + void xen_smp_intr_free_pv(unsigned int cpu) +diff --git a/include/linux/compiler.h b/include/linux/compiler.h +index 034b0a644efc..732754d96039 100644 +--- a/include/linux/compiler.h ++++ b/include/linux/compiler.h +@@ -356,4 +356,10 @@ static inline void *offset_to_ptr(const int *off) + /* &a[0] degrades to a pointer: a different type from an array */ + #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) + ++/* ++ * This is needed in functions which generate the stack canary, see ++ * arch/x86/kernel/smpboot.c::start_secondary() for an example. ++ */ ++#define prevent_tail_call_optimization() asm("") ++ + #endif /* __LINUX_COMPILER_H */ diff --git a/linux56-tkg/PKGBUILD b/linux56-tkg/PKGBUILD index d29b8cf..a73a8fe 100644 --- a/linux56-tkg/PKGBUILD +++ b/linux56-tkg/PKGBUILD @@ -89,7 +89,7 @@ pkgname=("${pkgbase}" "${pkgbase}-headers") _basekernel=5.6 _sub=12 pkgver="${_basekernel}"."${_sub}" -pkgrel=26 +pkgrel=27 pkgdesc='Linux-tkg' arch=('x86_64') # no i686 in here url="http://www.kernel.org/" @@ -133,7 +133,7 @@ sha256sums=('e342b04a2aa63808ea0ef1baab28fc520bd031ef8cf93d9ee4a31d4058fcb622' '66a03c246037451a77b4d448565b1d7e9368270c7d02872fbd0b5d024ed0a997' '31dc68e84aecfb7d069efb1305049122c65694676be8b955634abcf0675922a2' 'd02bf5ca08fd610394b9d3a0c3b176d74af206f897dee826e5cbaec97bb4a4aa' - 'a00a68f3689e187011d468e7112e95f7a525cc9e9369a106f02894ff37375ded' + '5987b3bd713d10fcd3c624785a1d0a8116325afab3e3752da6d4b1075b1a38d4' '7058e57fd68367b029adc77f2a82928f1433daaf02c8c279cb2d13556c8804d7' 'c605f638d74c61861ebdc36ebd4cb8b6475eae2f6273e1ccb2bbb3e10a2ec3fe' 'bc69d6e5ee8172b0242c8fa72d13cfe2b8d2b6601468836908a7dfe8b78a3bbb' diff --git a/linux56-tkg/linux56-tkg-patches/0003-glitched-base.patch b/linux56-tkg/linux56-tkg-patches/0003-glitched-base.patch index 0d1adf1..d86023d 100644 --- a/linux56-tkg/linux56-tkg-patches/0003-glitched-base.patch +++ b/linux56-tkg/linux56-tkg-patches/0003-glitched-base.patch @@ -1745,3 +1745,129 @@ diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c /* Update ghc->generation before performing any error checks. */ ghc->generation = slots->generation; + +rom f670269a42bfdd2c83a1118cc3d1b475547eac22 Mon Sep 17 00:00:00 2001 +From: Borislav Petkov +Date: Wed, 22 Apr 2020 18:11:30 +0200 +Subject: x86: Fix early boot crash on gcc-10, next try + +... or the odyssey of trying to disable the stack protector for the +function which generates the stack canary value. + +The whole story started with Sergei reporting a boot crash with a kernel +built with gcc-10: + + Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary + CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 + Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 + Call Trace: + dump_stack + panic + ? start_secondary + __stack_chk_fail + start_secondary + secondary_startup_64 + -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary + +This happens because gcc-10 tail-call optimizes the last function call +in start_secondary() - cpu_startup_entry() - and thus emits a stack +canary check which fails because the canary value changes after the +boot_init_stack_canary() call. + +To fix that, the initial attempt was to mark the one function which +generates the stack canary with: + + __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) + +however, using the optimize attribute doesn't work cumulatively +as the attribute does not add to but rather replaces previously +supplied optimization options - roughly all -fxxx options. + +The key one among them being -fno-omit-frame-pointer and thus leading to +not present frame pointer - frame pointer which the kernel needs. + +The next attempt to prevent compilers from tail-call optimizing +the last function call cpu_startup_entry(), shy of carving out +start_secondary() into a separate compilation unit and building it with + -fno-stack-protector, is this one. + +The current solution is short and sweet, and reportedly, is supported by +both compilers so let's see how far we'll get this time. + +Reported-by: Sergei Trofimovich +Signed-off-by: Borislav Petkov +Reviewed-by: Nick Desaulniers +Reviewed-by: Kees Cook +Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org +--- + arch/x86/include/asm/stackprotector.h | 7 ++++++- + arch/x86/kernel/smpboot.c | 8 ++++++++ + arch/x86/xen/smp_pv.c | 1 + + include/linux/compiler.h | 6 ++++++ + 4 files changed, 21 insertions(+), 1 deletion(-) + +diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h +index 91e29b6a86a5..9804a7957f4e 100644 +--- a/arch/x86/include/asm/stackprotector.h ++++ b/arch/x86/include/asm/stackprotector.h +@@ -55,8 +55,13 @@ + /* + * Initialize the stackprotector canary value. + * +- * NOTE: this must only be called from functions that never return, ++ * NOTE: this must only be called from functions that never return + * and it must always be inlined. ++ * ++ * In addition, it should be called from a compilation unit for which ++ * stack protector is disabled. Alternatively, the caller should not end ++ * with a function call which gets tail-call optimized as that would ++ * lead to checking a modified canary value. + */ + static __always_inline void boot_init_stack_canary(void) + { +diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c +index fe3ab9632f3b..4f275ac7830b 100644 +--- a/arch/x86/kernel/smpboot.c ++++ b/arch/x86/kernel/smpboot.c +@@ -266,6 +266,14 @@ static void notrace start_secondary(void *unused) + + wmb(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ ++ /* ++ * Prevent tail call to cpu_startup_entry() because the stack protector ++ * guard has been changed a couple of function calls up, in ++ * boot_init_stack_canary() and must not be checked before tail calling ++ * another function. ++ */ ++ prevent_tail_call_optimization(); + } + + /** +diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c +index 8fb8a50a28b4..f2adb63b2d7c 100644 +--- a/arch/x86/xen/smp_pv.c ++++ b/arch/x86/xen/smp_pv.c +@@ -93,6 +93,7 @@ asmlinkage __visible void cpu_bringup_and_idle(void) + cpu_bringup(); + boot_init_stack_canary(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ prevent_tail_call_optimization(); + } + + void xen_smp_intr_free_pv(unsigned int cpu) +diff --git a/include/linux/compiler.h b/include/linux/compiler.h +index 034b0a644efc..732754d96039 100644 +--- a/include/linux/compiler.h ++++ b/include/linux/compiler.h +@@ -356,4 +356,10 @@ static inline void *offset_to_ptr(const int *off) + /* &a[0] degrades to a pointer: a different type from an array */ + #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) + ++/* ++ * This is needed in functions which generate the stack canary, see ++ * arch/x86/kernel/smpboot.c::start_secondary() for an example. ++ */ ++#define prevent_tail_call_optimization() asm("") ++ + #endif /* __LINUX_COMPILER_H */ diff --git a/linux57-rc-tkg/PKGBUILD b/linux57-rc-tkg/PKGBUILD index a3d3c09..4e0a9d7 100644 --- a/linux57-rc-tkg/PKGBUILD +++ b/linux57-rc-tkg/PKGBUILD @@ -126,7 +126,7 @@ sha256sums=('0bed1c1d79abff19045870e93bdf8930e848502d25464ff01fd3b8d01de88a41' '66a03c246037451a77b4d448565b1d7e9368270c7d02872fbd0b5d024ed0a997' '31dc68e84aecfb7d069efb1305049122c65694676be8b955634abcf0675922a2' 'd02bf5ca08fd610394b9d3a0c3b176d74af206f897dee826e5cbaec97bb4a4aa' - '8352d688733b23472d10aa2fec3f604606fdeb957bc35f4851831a9b624556b8' + 'b641a948e9f98a2cdb4ae7f541a1376ebd390ff3404affe611d6a10e2a98e0ab' '7058e57fd68367b029adc77f2a82928f1433daaf02c8c279cb2d13556c8804d7' '62496f9ca788996181ef145f96ad26291282fcc3fb95cdc04080dcf84365be33' '7fd8e776209dac98627453fda754bdf9aff4a09f27cb0b3766d7983612eb3c74' diff --git a/linux57-rc-tkg/linux57-tkg-patches/0003-glitched-base.patch b/linux57-rc-tkg/linux57-tkg-patches/0003-glitched-base.patch index 318e776..234df6d 100644 --- a/linux57-rc-tkg/linux57-tkg-patches/0003-glitched-base.patch +++ b/linux57-rc-tkg/linux57-tkg-patches/0003-glitched-base.patch @@ -1444,3 +1444,129 @@ index d2fa3e9ccd97c..bd10cb02fc0ff 100644 if (!strcmp(str, "force")) force_load = 1; if (!strcmp(str, "hwp_only")) + +From f670269a42bfdd2c83a1118cc3d1b475547eac22 Mon Sep 17 00:00:00 2001 +From: Borislav Petkov +Date: Wed, 22 Apr 2020 18:11:30 +0200 +Subject: x86: Fix early boot crash on gcc-10, next try + +... or the odyssey of trying to disable the stack protector for the +function which generates the stack canary value. + +The whole story started with Sergei reporting a boot crash with a kernel +built with gcc-10: + + Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary + CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 + Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 + Call Trace: + dump_stack + panic + ? start_secondary + __stack_chk_fail + start_secondary + secondary_startup_64 + -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary + +This happens because gcc-10 tail-call optimizes the last function call +in start_secondary() - cpu_startup_entry() - and thus emits a stack +canary check which fails because the canary value changes after the +boot_init_stack_canary() call. + +To fix that, the initial attempt was to mark the one function which +generates the stack canary with: + + __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) + +however, using the optimize attribute doesn't work cumulatively +as the attribute does not add to but rather replaces previously +supplied optimization options - roughly all -fxxx options. + +The key one among them being -fno-omit-frame-pointer and thus leading to +not present frame pointer - frame pointer which the kernel needs. + +The next attempt to prevent compilers from tail-call optimizing +the last function call cpu_startup_entry(), shy of carving out +start_secondary() into a separate compilation unit and building it with + -fno-stack-protector, is this one. + +The current solution is short and sweet, and reportedly, is supported by +both compilers so let's see how far we'll get this time. + +Reported-by: Sergei Trofimovich +Signed-off-by: Borislav Petkov +Reviewed-by: Nick Desaulniers +Reviewed-by: Kees Cook +Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org +--- + arch/x86/include/asm/stackprotector.h | 7 ++++++- + arch/x86/kernel/smpboot.c | 8 ++++++++ + arch/x86/xen/smp_pv.c | 1 + + include/linux/compiler.h | 6 ++++++ + 4 files changed, 21 insertions(+), 1 deletion(-) + +diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h +index 91e29b6a86a5..9804a7957f4e 100644 +--- a/arch/x86/include/asm/stackprotector.h ++++ b/arch/x86/include/asm/stackprotector.h +@@ -55,8 +55,13 @@ + /* + * Initialize the stackprotector canary value. + * +- * NOTE: this must only be called from functions that never return, ++ * NOTE: this must only be called from functions that never return + * and it must always be inlined. ++ * ++ * In addition, it should be called from a compilation unit for which ++ * stack protector is disabled. Alternatively, the caller should not end ++ * with a function call which gets tail-call optimized as that would ++ * lead to checking a modified canary value. + */ + static __always_inline void boot_init_stack_canary(void) + { +diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c +index fe3ab9632f3b..4f275ac7830b 100644 +--- a/arch/x86/kernel/smpboot.c ++++ b/arch/x86/kernel/smpboot.c +@@ -266,6 +266,14 @@ static void notrace start_secondary(void *unused) + + wmb(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ ++ /* ++ * Prevent tail call to cpu_startup_entry() because the stack protector ++ * guard has been changed a couple of function calls up, in ++ * boot_init_stack_canary() and must not be checked before tail calling ++ * another function. ++ */ ++ prevent_tail_call_optimization(); + } + + /** +diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c +index 8fb8a50a28b4..f2adb63b2d7c 100644 +--- a/arch/x86/xen/smp_pv.c ++++ b/arch/x86/xen/smp_pv.c +@@ -93,6 +93,7 @@ asmlinkage __visible void cpu_bringup_and_idle(void) + cpu_bringup(); + boot_init_stack_canary(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ prevent_tail_call_optimization(); + } + + void xen_smp_intr_free_pv(unsigned int cpu) +diff --git a/include/linux/compiler.h b/include/linux/compiler.h +index 034b0a644efc..732754d96039 100644 +--- a/include/linux/compiler.h ++++ b/include/linux/compiler.h +@@ -356,4 +356,10 @@ static inline void *offset_to_ptr(const int *off) + /* &a[0] degrades to a pointer: a different type from an array */ + #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) + ++/* ++ * This is needed in functions which generate the stack canary, see ++ * arch/x86/kernel/smpboot.c::start_secondary() for an example. ++ */ ++#define prevent_tail_call_optimization() asm("") ++ + #endif /* __LINUX_COMPILER_H */