commit defb80a20bf1e4d778596ce2447e19d44f31ae5a Author: Sven Schnelle Date: Thu Dec 16 12:43:52 2021 +0100 s390: add variable command line size Newer s390 kernels support a command line size longer than 896 bytes. Such kernels contain a new member in the parameter area, which might be utilized by tools like kexec. Older kernels have the location initialized to zero, so we check whether there's a non-zero number present and use that. If there isn't, we fallback to the legacy command line size of 896 bytes. Signed-off-by: Sven Schnelle Reviewed-by: Alexander Egorenkov Signed-off-by: Simon Horman diff --git a/kexec/arch/s390/crashdump-s390.c b/kexec/arch/s390/crashdump-s390.c index 10f4d607bbcc1aea362de3de687b0e7b2401d879..3bd9efe6dafebab2f364c656ae703c71c4494c35 100644 --- a/kexec/arch/s390/crashdump-s390.c +++ b/kexec/arch/s390/crashdump-s390.c @@ -52,7 +52,8 @@ static int create_elf_header(struct kexec_info *info, unsigned long crash_base, elfcorehdr_size = bufsz; snprintf(str, sizeof(str), " elfcorehdr=%ld@%ldK\n", elfcorehdr_size, elfcorehdr / 1024); - command_line_add(str); + if (command_line_add(info, str)) + return -1; #endif return 0; } diff --git a/kexec/arch/s390/kexec-image.c b/kexec/arch/s390/kexec-image.c index 3c24fdfe3c7ccafddee9fb4a68c0d8874cf6a61e..a52399eafd2abd4a24142f0512251598ea812ca5 100644 --- a/kexec/arch/s390/kexec-image.c +++ b/kexec/arch/s390/kexec-image.c @@ -25,7 +25,6 @@ #include static uint64_t crash_base, crash_end; -static char command_line[COMMAND_LINESIZE]; static void add_segment_check(struct kexec_info *info, const void *buf, size_t bufsz, unsigned long base, size_t memsz) @@ -36,13 +35,18 @@ static void add_segment_check(struct kexec_info *info, const void *buf, add_segment(info, buf, bufsz, crash_base + base, memsz); } -int command_line_add(const char *str) +int command_line_add(struct kexec_info *info, const char *str) { - if (strlen(command_line) + strlen(str) + 1 > COMMAND_LINESIZE) { - fprintf(stderr, "Command line too long.\n"); + char *tmp = NULL; + + tmp = concat_cmdline(info->command_line, str); + if (!tmp) { + fprintf(stderr, "out of memory\n"); return -1; } - strcat(command_line, str); + + free(info->command_line); + info->command_line = tmp; return 0; } @@ -64,7 +68,7 @@ int image_s390_load_file(int argc, char **argv, struct kexec_info *info) while ((opt = getopt_long(argc, argv, short_options, options, 0)) != -1) { switch(opt) { case OPT_APPEND: - if (command_line_add(optarg)) + if (command_line_add(info, optarg)) return -1; break; case OPT_RAMDISK: @@ -78,13 +82,16 @@ int image_s390_load_file(int argc, char **argv, struct kexec_info *info) if (info->initrd_fd == -1) { fprintf(stderr, "Could not open initrd file %s:%s\n", ramdisk, strerror(errno)); + free(info->command_line); + info->command_line = NULL; return -1; } } - info->command_line = command_line; - info->command_line_len = strlen (command_line) + 1; - + if (info->command_line) + info->command_line_len = strlen(info->command_line) + 1; + else + info->command_line_len = 0; return 0; } @@ -97,7 +104,7 @@ image_s390_load(int argc, char **argv, const char *kernel_buf, const char *ramdisk; off_t ramdisk_len; unsigned int ramdisk_origin; - int opt; + int opt, ret = -1; if (info->file_mode) return image_s390_load_file(argc, argv, info); @@ -120,7 +126,7 @@ image_s390_load(int argc, char **argv, const char *kernel_buf, while ((opt = getopt_long(argc,argv,short_options,options,0)) != -1) { switch(opt) { case OPT_APPEND: - if (command_line_add(optarg)) + if (command_line_add(info, optarg)) return -1; break; case OPT_RAMDISK: @@ -132,7 +138,7 @@ image_s390_load(int argc, char **argv, const char *kernel_buf, if (info->kexec_flags & KEXEC_ON_CRASH) { if (parse_iomem_single("Crash kernel\n", &crash_base, &crash_end)) - return -1; + goto out; } /* Add kernel segment */ @@ -151,7 +157,7 @@ image_s390_load(int argc, char **argv, const char *kernel_buf, rd_buffer = slurp_file_mmap(ramdisk, &ramdisk_len); if (rd_buffer == NULL) { fprintf(stderr, "Could not read ramdisk.\n"); - return -1; + goto out; } ramdisk_origin = MAX(RAMDISK_ORIGIN_ADDR, kernel_size); ramdisk_origin = _ALIGN_UP(ramdisk_origin, 0x100000); @@ -160,7 +166,7 @@ image_s390_load(int argc, char **argv, const char *kernel_buf, } if (info->kexec_flags & KEXEC_ON_CRASH) { if (load_crashdump_segments(info, crash_base, crash_end)) - return -1; + goto out; } else { info->entry = (void *) IMAGE_READ_OFFSET; } @@ -183,15 +189,28 @@ image_s390_load(int argc, char **argv, const char *kernel_buf, *tmp = crash_end - crash_base + 1; } } - /* - * We will write a probably given command line. - * First, erase the old area, then setup the new parameters: - */ - if (strlen(command_line) != 0) { - memset(krnl_buffer + COMMAND_LINE_OFFS, 0, COMMAND_LINESIZE); - memcpy(krnl_buffer + COMMAND_LINE_OFFS, command_line, strlen(command_line)); + + if (info->command_line) { + unsigned long maxsize; + char *dest = krnl_buffer + COMMAND_LINE_OFFS; + + maxsize = *(unsigned long *)(krnl_buffer + MAX_COMMAND_LINESIZE_OFFS); + if (!maxsize) + maxsize = LEGACY_COMMAND_LINESIZE; + + if (strlen(info->command_line) > maxsize-1) { + fprintf(stderr, "command line too long, maximum allowed size %ld\n", + maxsize-1); + goto out; + } + strncpy(dest, info->command_line, maxsize-1); + dest[maxsize-1] = '\0'; } - return 0; + ret = 0; +out: + free(info->command_line); + info->command_line = NULL; + return ret; } int diff --git a/kexec/arch/s390/kexec-s390.h b/kexec/arch/s390/kexec-s390.h index ef53b111e16719d15e5364c18435e272f98b9086..6a99518c1c9e411ed853489daf0de6463972ab6f 100644 --- a/kexec/arch/s390/kexec-s390.h +++ b/kexec/arch/s390/kexec-s390.h @@ -10,16 +10,17 @@ #ifndef KEXEC_S390_H #define KEXEC_S390_H -#define IMAGE_READ_OFFSET 0x10000 +#define IMAGE_READ_OFFSET 0x10000 -#define RAMDISK_ORIGIN_ADDR 0x800000 -#define INITRD_START_OFFS 0x408 -#define INITRD_SIZE_OFFS 0x410 -#define OLDMEM_BASE_OFFS 0x418 -#define OLDMEM_SIZE_OFFS 0x420 -#define COMMAND_LINE_OFFS 0x480 -#define COMMAND_LINESIZE 896 -#define MAX_MEMORY_RANGES 1024 +#define RAMDISK_ORIGIN_ADDR 0x800000 +#define INITRD_START_OFFS 0x408 +#define INITRD_SIZE_OFFS 0x410 +#define OLDMEM_BASE_OFFS 0x418 +#define OLDMEM_SIZE_OFFS 0x420 +#define MAX_COMMAND_LINESIZE_OFFS 0x430 +#define COMMAND_LINE_OFFS 0x480 +#define LEGACY_COMMAND_LINESIZE 896 +#define MAX_MEMORY_RANGES 1024 #define MAX(x, y) ((x) > (y) ? (x) : (y)) #define MIN(x, y) ((x) < (y) ? (x) : (y)) @@ -32,6 +33,6 @@ extern int load_crashdump_segments(struct kexec_info *info, unsigned long crash_end); extern int get_memory_ranges_s390(struct memory_range range[], int *ranges, int with_crashk); -extern int command_line_add(const char *str); +extern int command_line_add(struct kexec_info *info, const char *str); #endif /* KEXEC_S390_H */