From 04d82a6d0881ef1ab1e9f66f10805177ee2fb1e8 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Sat, 17 Apr 2021 10:10:08 +0900 Subject: [PATCH 1/3] binfmt_flat: allow not offsetting data start Commit 2217b9826246 ("binfmt_flat: revert "binfmt_flat: don't offset the data start"") restored offsetting the start of the data section by a number of words defined by MAX_SHARED_LIBS. As a result, since MAX_SHARED_LIBS is never 0, a gap between the text and data sections always exists. For architectures which cannot support a such gap between the text and data sections (e.g. riscv nommu), flat binary programs cannot be executed. To allow an architecture to request no data start offset to allow for contiguous text and data sections for binaries flagged with FLAT_FLAG_RAM, introduce the new config option CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET. Using this new option, the macro DATA_START_OFFSET_WORDS is conditionally defined in binfmt_flat.c to MAX_SHARED_LIBS for architectures tolerating or needing the data start offset (CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET disabled case) and to 0 when CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET is enabled. DATA_START_OFFSET_WORDS is used in load_flat_file() to calculate the data section length and start position. Signed-off-by: Damien Le Moal Signed-off-by: Greg Ungerer --- fs/Kconfig.binfmt | 3 +++ fs/binfmt_flat.c | 18 +++++++++++++----- 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt index c6f1c8c1934e..06fb7a93a1bd 100644 --- a/fs/Kconfig.binfmt +++ b/fs/Kconfig.binfmt @@ -112,6 +112,9 @@ config BINFMT_FLAT_ARGVP_ENVP_ON_STACK config BINFMT_FLAT_OLD_ALWAYS_RAM bool +config BINFMT_FLAT_NO_DATA_START_OFFSET + bool + config BINFMT_FLAT_OLD bool "Enable support for very old legacy flat binaries" depends on BINFMT_FLAT diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index b9c658e0548e..a1072c6a2341 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -74,6 +74,12 @@ #define MAX_SHARED_LIBS (1) #endif +#ifdef CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET +#define DATA_START_OFFSET_WORDS (0) +#else +#define DATA_START_OFFSET_WORDS (MAX_SHARED_LIBS) +#endif + struct lib_info { struct { unsigned long start_code; /* Start of text segment */ @@ -576,7 +582,8 @@ static int load_flat_file(struct linux_binprm *bprm, goto err; } - len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); + len = data_len + extra + + DATA_START_OFFSET_WORDS * sizeof(unsigned long); len = PAGE_ALIGN(len); realdatastart = vm_mmap(NULL, 0, len, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0); @@ -591,7 +598,7 @@ static int load_flat_file(struct linux_binprm *bprm, goto err; } datapos = ALIGN(realdatastart + - MAX_SHARED_LIBS * sizeof(unsigned long), + DATA_START_OFFSET_WORDS * sizeof(unsigned long), FLAT_DATA_ALIGN); pr_debug("Allocated data+bss+stack (%u bytes): %lx\n", @@ -622,7 +629,8 @@ static int load_flat_file(struct linux_binprm *bprm, memp_size = len; } else { - len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(u32); + len = text_len + data_len + extra + + DATA_START_OFFSET_WORDS * sizeof(u32); len = PAGE_ALIGN(len); textpos = vm_mmap(NULL, 0, len, PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0); @@ -638,7 +646,7 @@ static int load_flat_file(struct linux_binprm *bprm, realdatastart = textpos + ntohl(hdr->data_start); datapos = ALIGN(realdatastart + - MAX_SHARED_LIBS * sizeof(u32), + DATA_START_OFFSET_WORDS * sizeof(u32), FLAT_DATA_ALIGN); reloc = (__be32 __user *) @@ -714,7 +722,7 @@ static int load_flat_file(struct linux_binprm *bprm, ret = result; pr_err("Unable to read code+data+bss, errno %d\n", ret); vm_munmap(textpos, text_len + data_len + extra + - MAX_SHARED_LIBS * sizeof(u32)); + DATA_START_OFFSET_WORDS * sizeof(u32)); goto err; } } From 09accc3a05f7f1a6486f4a278d209ac122289c0b Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Sat, 17 Apr 2021 10:10:09 +0900 Subject: [PATCH 2/3] riscv: Disable data start offset in flat binaries uclibc/gcc combined with elf2flt riscv linker file fully resolve the PC relative __global_pointer$ value at compile time and do not generate a relocation entry to set a correct value of the gp register at runtime. As a result, if the flatbin loader offsets the start of the data section, the relative position change between the text and data sections compared to the compile time positions results in an incorrect gp value being used. This causes flatbin executables to crash. Avoid this problem by enabling CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET automatically when CONFIG_RISCV is enabled and CONFIG_MMU is disabled. Signed-off-by: Damien Le Moal Acked-by: Palmer Dabbelt Signed-off-by: Greg Ungerer --- arch/riscv/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 4515a10c5d22..add528eb9235 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -33,6 +33,7 @@ config RISCV select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select ARCH_WANT_FRAME_POINTERS select ARCH_WANT_HUGE_PMD_SHARE if 64BIT + select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU select CLONE_BACKWARDS select CLINT_TIMER if !MMU select COMMON_CLK From 6b3788e5fb8041211ac2fa7c818ca9010e976a74 Mon Sep 17 00:00:00 2001 From: Angelo Dureghello Date: Thu, 8 Apr 2021 23:37:40 +0200 Subject: [PATCH 3/3] m68k: coldfire: fix irq ranges Working on flexcan0, there was no way to have irq 128 working. Fix irq 128 and 196 setup. Signed-off-by: Angelo Dureghello Reviewed-by: Geert Uytterhoeven Signed-off-by: Greg Ungerer --- arch/m68k/coldfire/intc-simr.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/m68k/coldfire/intc-simr.c b/arch/m68k/coldfire/intc-simr.c index 15c4b7a6e38f..f7c2c41b3156 100644 --- a/arch/m68k/coldfire/intc-simr.c +++ b/arch/m68k/coldfire/intc-simr.c @@ -68,9 +68,9 @@ static void intc_irq_mask(struct irq_data *d) { unsigned int irq = d->irq - MCFINT_VECBASE; - if (MCFINTC2_SIMR && (irq > 128)) + if (MCFINTC2_SIMR && (irq > 127)) __raw_writeb(irq - 128, MCFINTC2_SIMR); - else if (MCFINTC1_SIMR && (irq > 64)) + else if (MCFINTC1_SIMR && (irq > 63)) __raw_writeb(irq - 64, MCFINTC1_SIMR); else __raw_writeb(irq, MCFINTC0_SIMR); @@ -80,9 +80,9 @@ static void intc_irq_unmask(struct irq_data *d) { unsigned int irq = d->irq - MCFINT_VECBASE; - if (MCFINTC2_CIMR && (irq > 128)) + if (MCFINTC2_CIMR && (irq > 127)) __raw_writeb(irq - 128, MCFINTC2_CIMR); - else if (MCFINTC1_CIMR && (irq > 64)) + else if (MCFINTC1_CIMR && (irq > 63)) __raw_writeb(irq - 64, MCFINTC1_CIMR); else __raw_writeb(irq, MCFINTC0_CIMR); @@ -115,9 +115,9 @@ static unsigned int intc_irq_startup(struct irq_data *d) } irq -= MCFINT_VECBASE; - if (MCFINTC2_ICR0 && (irq > 128)) + if (MCFINTC2_ICR0 && (irq > 127)) __raw_writeb(5, MCFINTC2_ICR0 + irq - 128); - else if (MCFINTC1_ICR0 && (irq > 64)) + else if (MCFINTC1_ICR0 && (irq > 63)) __raw_writeb(5, MCFINTC1_ICR0 + irq - 64); else __raw_writeb(5, MCFINTC0_ICR0 + irq);