Date: Sat, 21 Apr 2012 20:10:26 +0000 (UTC) From: Rafal Jaworowski <raj@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r234558 - in stable/9/sys: boot/fdt boot/uboot/common i386/conf kern Message-ID: <201204212010.q3LKAQgK003292@svn.freebsd.org>
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Author: raj Date: Sat Apr 21 20:10:26 2012 New Revision: 234558 URL: http://svn.freebsd.org/changeset/base/234558 Log: MFC r233230, r233323: Improve device tree blob (DTB) handling in loader(8). Enable using the statically embedded blob from the kernel, if present. The KLD loaded DTB takes precedence, but they are both recognized and handled in the same way. Improve FDT handling in loader(8) and make it more robust. o Fix buffer overflows when using a long property body in node paths. o Fix loop end condition when iterating through the symbol table. o Better error handling during node modification, better problem reporting. o Eliminate build time warnings. Submitted by: Lukasz Wojcik Obtained from: Semihalf Modified: stable/9/sys/boot/fdt/fdt_loader_cmd.c stable/9/sys/boot/uboot/common/metadata.c Directory Properties: stable/9/sys/ (props changed) stable/9/sys/amd64/include/xen/ (props changed) stable/9/sys/boot/ (props changed) stable/9/sys/boot/i386/efi/ (props changed) stable/9/sys/boot/ia64/efi/ (props changed) stable/9/sys/boot/ia64/ski/ (props changed) stable/9/sys/boot/powerpc/boot1.chrp/ (props changed) stable/9/sys/boot/powerpc/ofw/ (props changed) stable/9/sys/cddl/contrib/opensolaris/ (props changed) stable/9/sys/conf/ (props changed) stable/9/sys/contrib/dev/acpica/ (props changed) stable/9/sys/contrib/octeon-sdk/ (props changed) stable/9/sys/contrib/pf/ (props changed) stable/9/sys/contrib/x86emu/ (props changed) stable/9/sys/fs/ (props changed) stable/9/sys/fs/ntfs/ (props changed) stable/9/sys/i386/conf/XENHVM (props changed) stable/9/sys/kern/subr_witness.c (props changed) Modified: stable/9/sys/boot/fdt/fdt_loader_cmd.c ============================================================================== --- stable/9/sys/boot/fdt/fdt_loader_cmd.c Sat Apr 21 19:22:53 2012 (r234557) +++ stable/9/sys/boot/fdt/fdt_loader_cmd.c Sat Apr 21 20:10:26 2012 (r234558) @@ -33,6 +33,9 @@ __FBSDID("$FreeBSD$"); #include <stand.h> #include <fdt.h> #include <libfdt.h> +#include <sys/param.h> +#include <sys/linker.h> +#include <machine/elf.h> #include "bootstrap.h" #include "glue.h" @@ -54,7 +57,9 @@ __FBSDID("$FreeBSD$"); #define STR(number) #number #define STRINGIFY(number) STR(number) -#define MIN(num1, num2) (((num1) < (num2)) ? (num1):(num2)) +#define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l) + +#define FDT_STATIC_DTB_SYMBOL "fdt_static_dtb" static struct fdt_header *fdtp = NULL; @@ -92,6 +97,91 @@ static const struct cmdtab commands[] = static char cwd[FDT_CWD_LEN] = "/"; +static vm_offset_t +fdt_find_static_dtb(void) +{ + Elf_Sym sym; + vm_offset_t dyntab, esym; + uint64_t offs; + struct preloaded_file *kfp; + struct file_metadata *md; + Elf_Sym *symtab; + Elf_Dyn *dyn; + char *strtab, *strp; + int i, sym_count; + + symtab = NULL; + dyntab = esym = 0; + strtab = strp = NULL; + + offs = __elfN(relocation_offset); + + kfp = file_findfile(NULL, NULL); + if (kfp == NULL) + return (0); + + md = file_findmetadata(kfp, MODINFOMD_ESYM); + if (md == NULL) + return (0); + COPYOUT(md->md_data, &esym, sizeof(esym)); + + md = file_findmetadata(kfp, MODINFOMD_DYNAMIC); + if (md == NULL) + return (0); + COPYOUT(md->md_data, &dyntab, sizeof(dyntab)); + + dyntab += offs; + + /* Locate STRTAB and DYNTAB */ + for (dyn = (Elf_Dyn *)dyntab; dyn->d_tag != DT_NULL; dyn++) { + if (dyn->d_tag == DT_STRTAB) { + strtab = (char *)(uintptr_t)(dyn->d_un.d_ptr + offs); + continue; + } else if (dyn->d_tag == DT_SYMTAB) { + symtab = (Elf_Sym *)(uintptr_t) + (dyn->d_un.d_ptr + offs); + continue; + } + } + + if (symtab == NULL || strtab == NULL) { + /* + * No symtab? No strtab? That should not happen here, + * and should have been verified during __elfN(loadimage). + * This must be some kind of a bug. + */ + return (0); + } + + sym_count = (int)((Elf_Sym *)esym - symtab) / sizeof(Elf_Sym); + + /* + * The most efficent way to find a symbol would be to calculate a + * hash, find proper bucket and chain, and thus find a symbol. + * However, that would involve code duplication (e.g. for hash + * function). So we're using simpler and a bit slower way: we're + * iterating through symbols, searching for the one which name is + * 'equal' to 'fdt_static_dtb'. To speed up the process a little bit, + * we are eliminating symbols type of which is not STT_NOTYPE, or(and) + * those which binding attribute is not STB_GLOBAL. + */ + for (i = 0; i < sym_count; i++) { + COPYOUT(symtab + i, &sym, sizeof(sym)); + if (ELF_ST_BIND(sym.st_info) != STB_GLOBAL || + ELF_ST_TYPE(sym.st_info) != STT_NOTYPE) + continue; + + strp = strdupout((vm_offset_t)(strtab + sym.st_name)); + if (strcmp(strp, FDT_STATIC_DTB_SYMBOL) == 0) { + /* Found a match ! */ + free(strp); + return ((vm_offset_t)(sym.st_value + offs)); + } + free(strp); + } + return (0); +} + static int fdt_setup_fdtp() { @@ -103,10 +193,14 @@ fdt_setup_fdtp() */ bfp = file_findfile(NULL, "dtb"); if (bfp == NULL) { - command_errmsg = "no device tree blob loaded"; - return (CMD_ERROR); + if ((fdtp = (struct fdt_header *)fdt_find_static_dtb()) == 0) { + command_errmsg = "no device tree blob found!"; + return (CMD_ERROR); + } + } else { + /* Dynamic blob has precedence over static. */ + fdtp = (struct fdt_header *)bfp->f_addr; } - fdtp = (struct fdt_header *)bfp->f_addr; /* * Validate the blob. @@ -448,7 +542,10 @@ fixup_stdout(const char *env) } } -int +/* + * Locate the blob, fix it up and return its location. + */ +void * fdt_fixup(void) { const char *env; @@ -461,13 +558,10 @@ fdt_fixup(void) ethstr = NULL; len = 0; - if (!fdtp) { - err = fdt_setup_fdtp(); - if (err) { - sprintf(command_errbuf, "Could not perform blob " - "fixups. Error code: %d\n", err); - return (err); - } + err = fdt_setup_fdtp(); + if (err) { + sprintf(command_errbuf, "No valid device tree blob found!"); + return (NULL); } /* Create /chosen node (if not exists) */ @@ -477,7 +571,7 @@ fdt_fixup(void) /* Value assigned to fixup-applied does not matter. */ if (fdt_getprop(fdtp, chosen, "fixup-applied", NULL)) - return (CMD_OK); + goto success; /* Acquire sys_info */ si = ub_get_sys_info(); @@ -521,7 +615,8 @@ fdt_fixup(void) fdt_setprop(fdtp, chosen, "fixup-applied", NULL, 0); - return (CMD_OK); +success: + return (fdtp); } int @@ -539,7 +634,8 @@ command_fdt_internal(int argc, char *arg /* * Check if uboot env vars were parsed already. If not, do it now. */ - fdt_fixup(); + if (fdt_fixup() == NULL) + return (CMD_ERROR); /* * Validate fdt <command>. @@ -560,10 +656,6 @@ command_fdt_internal(int argc, char *arg return (CMD_ERROR); } - if (!fdtp) - if (fdt_setup_fdtp()) - return (CMD_ERROR); - /* * Call command handler. */ @@ -753,32 +845,41 @@ fdt_isprint(const void *data, int len, i static int fdt_data_str(const void *data, int len, int count, char **buf) { - char tmp[80], *b; + char *b, *tmp; const char *d; - int i, l; + int buf_len, i, l; /* * Calculate the length for the string and allocate memory. * - * Note len already includes at least one terminator. + * Note that 'len' already includes at least one terminator. */ - l = len; + buf_len = len; if (count > 1) { /* * Each token had already a terminator buried in 'len', but we * only need one eventually, don't count space for these. */ - l -= count - 1; + buf_len -= count - 1; /* Each consecutive token requires a ", " separator. */ - l += count * 2; + buf_len += count * 2; } - /* Space for surrounding double quotes. */ - l += count * 2; - b = (char *)malloc(l); + /* Add some space for surrounding double quotes. */ + buf_len += count * 2; + + /* Note that string being put in 'tmp' may be as big as 'buf_len'. */ + b = (char *)malloc(buf_len); + tmp = (char *)malloc(buf_len); if (b == NULL) - return (1); + goto error; + + if (tmp == NULL) { + free(b); + goto error; + } + b[0] = '\0'; /* @@ -798,13 +899,17 @@ fdt_data_str(const void *data, int len, } while (i < len); *buf = b; + free(tmp); + return (0); +error: + return (1); } static int fdt_data_cell(const void *data, int len, char **buf) { - char tmp[80], *b; + char *b, *tmp; const uint32_t *c; int count, i, l; @@ -827,8 +932,14 @@ fdt_data_cell(const void *data, int len, l += 3; b = (char *)malloc(l); + tmp = (char *)malloc(l); if (b == NULL) - return (1); + goto error; + + if (tmp == NULL) { + free(b); + goto error; + } b[0] = '\0'; strcat(b, "<"); @@ -842,13 +953,17 @@ fdt_data_cell(const void *data, int len, strcat(b, ">"); *buf = b; + free(tmp); + return (0); +error: + return (1); } static int fdt_data_bytes(const void *data, int len, char **buf) { - char tmp[80], *b; + char *b, *tmp; const char *d; int i, l; @@ -867,8 +982,14 @@ fdt_data_bytes(const void *data, int len l += 3; b = (char *)malloc(l); + tmp = (char *)malloc(l); if (b == NULL) - return (1); + goto error; + + if (tmp == NULL) { + free(b); + goto error; + } b[0] = '\0'; strcat(b, "["); @@ -880,7 +1001,11 @@ fdt_data_bytes(const void *data, int len strcat(b, "]"); *buf = b; + free(tmp); + return (0); +error: + return (1); } static int @@ -1019,6 +1144,14 @@ fdt_modprop(int nodeoff, char *propname, break; } + if (rv != 0) { + if (rv == -FDT_ERR_NOSPACE) + sprintf(command_errbuf, + "Device tree blob is too small!\n"); + else + sprintf(command_errbuf, + "Could not add/modify property!\n"); + } return (rv); } @@ -1261,9 +1394,12 @@ fdt_cmd_mknode(int argc, char *argv[]) rv = fdt_add_subnode(fdtp, o, nodename); if (rv < 0) { - sprintf(command_errbuf, "could not delete node %s\n", - (rv == -FDT_ERR_NOTFOUND) ? - "(node does not exist)" : ""); + if (rv == -FDT_ERR_NOSPACE) + sprintf(command_errbuf, + "Device tree blob is too small!\n"); + else + sprintf(command_errbuf, + "Could not add node!\n"); return (CMD_ERROR); } return (CMD_OK); @@ -1272,7 +1408,7 @@ fdt_cmd_mknode(int argc, char *argv[]) static int fdt_cmd_pwd(int argc, char *argv[]) { - char line[80]; + char line[FDT_CWD_LEN]; pager_open(); sprintf(line, "%s\n", cwd); Modified: stable/9/sys/boot/uboot/common/metadata.c ============================================================================== --- stable/9/sys/boot/uboot/common/metadata.c Sat Apr 21 19:22:53 2012 (r234557) +++ stable/9/sys/boot/uboot/common/metadata.c Sat Apr 21 20:10:26 2012 (r234558) @@ -333,13 +333,12 @@ md_load(char *args, vm_offset_t *modulep #if defined(LOADER_FDT_SUPPORT) /* Handle device tree blob */ - fdt_fixup(); - if ((bfp = file_findfile(NULL, "dtb")) == NULL && - (howto & RB_VERBOSE)) - printf("**WARNING** Booting with no DTB loaded!\n"); - - dtbp = bfp == NULL ? 0 : bfp->f_addr; - file_addmetadata(kfp, MODINFOMD_DTBP, sizeof dtbp, &dtbp); + dtbp = fdt_fixup(); + if (dtbp != (vm_offset_t)NULL) + file_addmetadata(kfp, MODINFOMD_DTBP, sizeof dtbp, &dtbp); + else + pager_output("WARNING! Trying to fire up the kernel, but no " + "device tree blob found!\n"); #endif file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
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