diff options
| -rw-r--r-- | scripts/recordmcount.c | 162 | ||||
| -rw-r--r-- | scripts/recordmcount.h | 141 |
2 files changed, 184 insertions, 119 deletions
diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 1fe5fba99959..c6d395b8ff29 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -27,7 +27,6 @@ #include <getopt.h> #include <elf.h> #include <fcntl.h> -#include <setjmp.h> #include <stdio.h> #include <stdlib.h> #include <string.h> @@ -43,7 +42,6 @@ static int fd_map; /* File descriptor for file being modified. */ static int mmap_failed; /* Boolean flag. */ static char gpfx; /* prefix for global symbol name (sometimes '_') */ static struct stat sb; /* Remember .st_size, etc. */ -static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */ static const char *altmcount; /* alternate mcount symbol name */ static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */ static void *file_map; /* pointer of the mapped file */ @@ -53,13 +51,6 @@ static void *file_ptr; /* current file pointer location */ static void *file_append; /* added to the end of the file */ static size_t file_append_size; /* how much is added to end of file */ -/* setjmp() return values */ -enum { - SJ_SETJMP = 0, /* hardwired first return */ - SJ_FAIL, - SJ_SUCCEED -}; - /* Per-file resource cleanup when multiple files. */ static void cleanup(void) @@ -75,20 +66,6 @@ cleanup(void) file_updated = 0; } -static void __attribute__((noreturn)) -fail_file(void) -{ - cleanup(); - longjmp(jmpenv, SJ_FAIL); -} - -static void __attribute__((noreturn)) -succeed_file(void) -{ - cleanup(); - longjmp(jmpenv, SJ_SUCCEED); -} - /* ulseek, uwrite, ...: Check return value for errors. */ static off_t @@ -107,12 +84,12 @@ ulseek(off_t const offset, int const whence) } if (file_ptr < file_map) { fprintf(stderr, "lseek: seek before file\n"); - fail_file(); + return -1; } return file_ptr - file_map; } -static size_t +static ssize_t uwrite(void const *const buf, size_t const count) { size_t cnt = count; @@ -129,7 +106,8 @@ uwrite(void const *const buf, size_t const count) } if (!file_append) { perror("write"); - fail_file(); + cleanup(); + return -1; } if (file_ptr < file_end) { cnt = file_end - file_ptr; @@ -155,7 +133,8 @@ umalloc(size_t size) void *const addr = malloc(size); if (addr == 0) { fprintf(stderr, "malloc failed: %zu bytes\n", size); - fail_file(); + cleanup(); + return NULL; } return addr; } @@ -183,8 +162,10 @@ static int make_nop_x86(void *map, size_t const offset) return -1; /* convert to nop */ - ulseek(offset - 1, SEEK_SET); - uwrite(ideal_nop, 5); + if (ulseek(offset - 1, SEEK_SET) < 0) + return -1; + if (uwrite(ideal_nop, 5) < 0) + return -1; return 0; } @@ -232,10 +213,12 @@ static int make_nop_arm(void *map, size_t const offset) return -1; /* Convert to nop */ - ulseek(off, SEEK_SET); + if (ulseek(off, SEEK_SET) < 0) + return -1; do { - uwrite(ideal_nop, nop_size); + if (uwrite(ideal_nop, nop_size) < 0) + return -1; } while (--cnt > 0); return 0; @@ -252,8 +235,10 @@ static int make_nop_arm64(void *map, size_t const offset) return -1; /* Convert to nop */ - ulseek(offset, SEEK_SET); - uwrite(ideal_nop, 4); + if (ulseek(offset, SEEK_SET) < 0) + return -1; + if (uwrite(ideal_nop, 4) < 0) + return -1; return 0; } @@ -272,14 +257,23 @@ static int make_nop_arm64(void *map, size_t const offset) */ static void *mmap_file(char const *fname) { + file_map = NULL; + sb.st_size = 0; fd_map = open(fname, O_RDONLY); - if (fd_map < 0 || fstat(fd_map, &sb) < 0) { + if (fd_map < 0) { + perror(fname); + cleanup(); + return NULL; + } + if (fstat(fd_map, &sb) < 0) { perror(fname); - fail_file(); + cleanup(); + goto out; } if (!S_ISREG(sb.st_mode)) { fprintf(stderr, "not a regular file: %s\n", fname); - fail_file(); + cleanup(); + goto out; } file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd_map, 0); @@ -287,11 +281,18 @@ static void *mmap_file(char const *fname) if (file_map == MAP_FAILED) { mmap_failed = 1; file_map = umalloc(sb.st_size); + if (!file_map) { + perror(fname); + goto out; + } if (read(fd_map, file_map, sb.st_size) != sb.st_size) { perror(fname); - fail_file(); + free(file_map); + file_map = NULL; + goto out; } } +out: close(fd_map); file_end = file_map + sb.st_size; @@ -299,13 +300,13 @@ static void *mmap_file(char const *fname) return file_map; } -static void write_file(const char *fname) +static int write_file(const char *fname) { char tmp_file[strlen(fname) + 4]; size_t n; if (!file_updated) - return; + return 0; sprintf(tmp_file, "%s.rc", fname); @@ -317,25 +318,32 @@ static void write_file(const char *fname) fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode); if (fd_map < 0) { perror(fname); - fail_file(); + cleanup(); + return -1; } n = write(fd_map, file_map, sb.st_size); if (n != sb.st_size) { perror("write"); - fail_file(); + cleanup(); + close(fd_map); + return -1; } if (file_append_size) { n = write(fd_map, file_append, file_append_size); if (n != file_append_size) { perror("write"); - fail_file(); + cleanup(); + close(fd_map); + return -1; } } close(fd_map); if (rename(tmp_file, fname) < 0) { perror(fname); - fail_file(); + cleanup(); + return -1; } + return 0; } /* w8rev, w8nat, ...: Handle endianness. */ @@ -400,6 +408,8 @@ is_mcounted_section_name(char const *const txtname) strcmp(".cpuidle.text", txtname) == 0; } +static char const *already_has_rel_mcount = "success"; /* our work here is done! */ + /* 32 bit and 64 bit are very similar */ #include "recordmcount.h" #define RECORD_MCOUNT_64 @@ -438,11 +448,15 @@ static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type) }).r_info; } -static void +static int do_file(char const *const fname) { Elf32_Ehdr *const ehdr = mmap_file(fname); unsigned int reltype = 0; + int rc = -1; + + if (!ehdr) + goto out; w = w4nat; w2 = w2nat; @@ -452,8 +466,8 @@ do_file(char const *const fname) default: fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", ehdr->e_ident[EI_DATA], fname); - fail_file(); - break; + cleanup(); + goto out; case ELFDATA2LSB: if (*(unsigned char const *)&endian != 1) { /* main() is big endian, file.o is little endian. */ @@ -485,7 +499,8 @@ do_file(char const *const fname) || w2(ehdr->e_type) != ET_REL || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { fprintf(stderr, "unrecognized ET_REL file %s\n", fname); - fail_file(); + cleanup(); + goto out; } gpfx = 0; @@ -493,8 +508,8 @@ do_file(char const *const fname) default: fprintf(stderr, "unrecognized e_machine %u %s\n", w2(ehdr->e_machine), fname); - fail_file(); - break; + cleanup(); + goto out; case EM_386: reltype = R_386_32; rel_type_nop = R_386_NONE; @@ -534,20 +549,22 @@ do_file(char const *const fname) default: fprintf(stderr, "unrecognized ELF class %d %s\n", ehdr->e_ident[EI_CLASS], fname); - fail_file(); - break; + cleanup(); + goto out; case ELFCLASS32: if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr) || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { fprintf(stderr, "unrecognized ET_REL file: %s\n", fname); - fail_file(); + cleanup(); + goto out; } if (w2(ehdr->e_machine) == EM_MIPS) { reltype = R_MIPS_32; is_fake_mcount32 = MIPS32_is_fake_mcount; } - do32(ehdr, fname, reltype); + if (do32(ehdr, fname, reltype) < 0) + goto out; break; case ELFCLASS64: { Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; @@ -555,7 +572,8 @@ do_file(char const *const fname) || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { fprintf(stderr, "unrecognized ET_REL file: %s\n", fname); - fail_file(); + cleanup(); + goto out; } if (w2(ghdr->e_machine) == EM_S390) { reltype = R_390_64; @@ -567,13 +585,16 @@ do_file(char const *const fname) Elf64_r_info = MIPS64_r_info; is_fake_mcount64 = MIPS64_is_fake_mcount; } - do64(ghdr, fname, reltype); + if (do64(ghdr, fname, reltype) < 0) + goto out; break; } } /* end switch */ - write_file(fname); + rc = write_file(fname); +out: cleanup(); + return rc; } int @@ -604,7 +625,6 @@ main(int argc, char *argv[]) /* Process each file in turn, allowing deep failure. */ for (i = optind; i < argc; i++) { char *file = argv[i]; - int const sjval = setjmp(jmpenv); int len; /* @@ -617,28 +637,16 @@ main(int argc, char *argv[]) strcmp(file + (len - ftrace_size), ftrace) == 0) continue; - switch (sjval) { - default: - fprintf(stderr, "internal error: %s\n", file); - exit(1); - break; - case SJ_SETJMP: /* normal sequence */ - /* Avoid problems if early cleanup() */ - fd_map = -1; - mmap_failed = 1; - file_map = NULL; - file_ptr = NULL; - file_updated = 0; - do_file(file); - break; - case SJ_FAIL: /* error in do_file or below */ + /* Avoid problems if early cleanup() */ + fd_map = -1; + mmap_failed = 1; + file_map = NULL; + file_ptr = NULL; + file_updated = 0; + if (do_file(file)) { fprintf(stderr, "%s: failed\n", file); ++n_error; - break; - case SJ_SUCCEED: /* premature success */ - /* do nothing */ - break; - } /* end switch */ + } } return !!n_error; } diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index c1e1b04b4871..3796eb37fb12 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -174,7 +174,7 @@ static int MIPS_is_fake_mcount(Elf_Rel const *rp) } /* Append the new shstrtab, Elf_Shdr[], __mcount_loc and its relocations. */ -static void append_func(Elf_Ehdr *const ehdr, +static int append_func(Elf_Ehdr *const ehdr, Elf_Shdr *const shstr, uint_t const *const mloc0, uint_t const *const mlocp, @@ -202,15 +202,20 @@ static void append_func(Elf_Ehdr *const ehdr, new_e_shoff = t; /* body for new shstrtab */ - ulseek(sb.st_size, SEEK_SET); - uwrite(old_shstr_sh_offset + (void *)ehdr, old_shstr_sh_size); - uwrite(mc_name, 1 + strlen(mc_name)); + if (ulseek(sb.st_size, SEEK_SET) < 0) + return -1; + if (uwrite(old_shstr_sh_offset + (void *)ehdr, old_shstr_sh_size) < 0) + return -1; + if (uwrite(mc_name, 1 + strlen(mc_name)) < 0) + return -1; /* old(modified) Elf_Shdr table, word-byte aligned */ - ulseek(t, SEEK_SET); + if (ulseek(t, SEEK_SET) < 0) + return -1; t += sizeof(Elf_Shdr) * old_shnum; - uwrite(old_shoff + (void *)ehdr, - sizeof(Elf_Shdr) * old_shnum); + if (uwrite(old_shoff + (void *)ehdr, + sizeof(Elf_Shdr) * old_shnum) < 0) + return -1; /* new sections __mcount_loc and .rel__mcount_loc */ t += 2*sizeof(mcsec); @@ -225,7 +230,8 @@ static void append_func(Elf_Ehdr *const ehdr, mcsec.sh_info = 0; mcsec.sh_addralign = _w(_size); mcsec.sh_entsize = _w(_size); - uwrite(&mcsec, sizeof(mcsec)); + if (uwrite(&mcsec, sizeof(mcsec)) < 0) + return -1; mcsec.sh_name = w(old_shstr_sh_size); mcsec.sh_type = (sizeof(Elf_Rela) == rel_entsize) @@ -239,15 +245,22 @@ static void append_func(Elf_Ehdr *const ehdr, mcsec.sh_info = w(old_shnum); mcsec.sh_addralign = _w(_size); mcsec.sh_entsize = _w(rel_entsize); - uwrite(&mcsec, sizeof(mcsec)); - uwrite(mloc0, (void *)mlocp - (void *)mloc0); - uwrite(mrel0, (void *)mrelp - (void *)mrel0); + if (uwrite(&mcsec, sizeof(mcsec)) < 0) + return -1; + + if (uwrite(mloc0, (void *)mlocp - (void *)mloc0) < 0) + return -1; + if (uwrite(mrel0, (void *)mrelp - (void *)mrel0) < 0) + return -1; ehdr->e_shoff = _w(new_e_shoff); ehdr->e_shnum = w2(2 + w2(ehdr->e_shnum)); /* {.rel,}__mcount_loc */ - ulseek(0, SEEK_SET); - uwrite(ehdr, sizeof(*ehdr)); + if (ulseek(0, SEEK_SET) < 0) + return -1; + if (uwrite(ehdr, sizeof(*ehdr)) < 0) + return -1; + return 0; } static unsigned get_mcountsym(Elf_Sym const *const sym0, @@ -351,9 +364,9 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, * that are not going to be traced. The mcount calls here will be converted * into nops. */ -static void nop_mcount(Elf_Shdr const *const relhdr, - Elf_Ehdr const *const ehdr, - const char *const txtname) +static int nop_mcount(Elf_Shdr const *const relhdr, + Elf_Ehdr const *const ehdr, + const char *const txtname) { Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + (void *)ehdr); @@ -376,15 +389,18 @@ static void nop_mcount(Elf_Shdr const *const relhdr, mcountsym = get_mcountsym(sym0, relp, str0); if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) { - if (make_nop) + if (make_nop) { ret = make_nop((void *)ehdr, _w(shdr->sh_offset) + _w(relp->r_offset)); + if (ret < 0) + return -1; + } if (warn_on_notrace_sect && !once) { printf("Section %s has mcount callers being ignored\n", txtname); once = 1; /* just warn? */ if (!make_nop) - return; + return 0; } } @@ -396,14 +412,16 @@ static void nop_mcount(Elf_Shdr const *const relhdr, Elf_Rel rel; rel = *(Elf_Rel *)relp; Elf_r_info(&rel, Elf_r_sym(relp), rel_type_nop); - ulseek((void *)relp - (void *)ehdr, SEEK_SET); - uwrite(&rel, sizeof(rel)); + if (ulseek((void *)relp - (void *)ehdr, SEEK_SET) < 0) + return -1; + if (uwrite(&rel, sizeof(rel)) < 0) + return -1; } relp = (Elf_Rel const *)(rel_entsize + (void *)relp); } + return 0; } - /* * Find a symbol in the given section, to be used as the base for relocating * the table of offsets of calls to mcount. A local or global symbol suffices, @@ -414,9 +432,10 @@ static void nop_mcount(Elf_Shdr const *const relhdr, * Num: Value Size Type Bind Vis Ndx Name * 2: 00000000 0 SECTION LOCAL DEFAULT 1 */ -static unsigned find_secsym_ndx(unsigned const txtndx, +static int find_secsym_ndx(unsigned const txtndx, char const *const txtname, uint_t *const recvalp, + unsigned int *sym_index, Elf_Shdr const *const symhdr, Elf_Ehdr const *const ehdr) { @@ -438,15 +457,16 @@ static unsigned find_secsym_ndx(unsigned const txtndx, continue; *recvalp = _w(symp->st_value); - return symp - sym0; + *sym_index = symp - sym0; + return 0; } } fprintf(stderr, "Cannot find symbol for section %u: %s.\n", txtndx, txtname); - fail_file(); + cleanup(); + return -1; } - /* Evade ISO C restriction: no declaration after statement in has_rel_mcount. */ static char const * __has_rel_mcount(Elf_Shdr const *const relhdr, /* is SHT_REL or SHT_RELA */ @@ -461,7 +481,8 @@ __has_rel_mcount(Elf_Shdr const *const relhdr, /* is SHT_REL or SHT_RELA */ if (strcmp("__mcount_loc", txtname) == 0) { fprintf(stderr, "warning: __mcount_loc already exists: %s\n", fname); - succeed_file(); + cleanup(); + return already_has_rel_mcount; } if (w(txthdr->sh_type) != SHT_PROGBITS || !(_w(txthdr->sh_flags) & SHF_EXECINSTR)) @@ -491,6 +512,10 @@ static unsigned tot_relsize(Elf_Shdr const *const shdr0, for (; nhdr; --nhdr, ++shdrp) { txtname = has_rel_mcount(shdrp, shdr0, shstrtab, fname); + if (txtname == already_has_rel_mcount) { + totrelsz = 0; + break; + } if (txtname && is_mcounted_section_name(txtname)) totrelsz += _w(shdrp->sh_size); } @@ -499,7 +524,7 @@ static unsigned tot_relsize(Elf_Shdr const *const shdr0, /* Overall supervision for Elf32 ET_REL file. */ -static void +static int do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) { Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) @@ -513,26 +538,54 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) unsigned k; /* Upper bound on space: assume all relevant relocs are for mcount. */ - unsigned const totrelsz = tot_relsize(shdr0, nhdr, shstrtab, fname); - Elf_Rel *const mrel0 = umalloc(totrelsz); - Elf_Rel * mrelp = mrel0; + unsigned totrelsz; - /* 2*sizeof(address) <= sizeof(Elf_Rel) */ - uint_t *const mloc0 = umalloc(totrelsz>>1); - uint_t * mlocp = mloc0; + Elf_Rel * mrel0; + Elf_Rel * mrelp; + + uint_t * mloc0; + uint_t * mlocp; unsigned rel_entsize = 0; unsigned symsec_sh_link = 0; + int result = 0; + + totrelsz = tot_relsize(shdr0, nhdr, shstrtab, fname); + if (totrelsz == 0) + return 0; + mrel0 = umalloc(totrelsz); + mrelp = mrel0; + if (!mrel0) + return -1; + + /* 2*sizeof(address) <= sizeof(Elf_Rel) */ + mloc0 = umalloc(totrelsz>>1); + mlocp = mloc0; + if (!mloc0) { + free(mrel0); + return -1; + } + for (relhdr = shdr0, k = nhdr; k; --k, ++relhdr) { char const *const txtname = has_rel_mcount(relhdr, shdr0, shstrtab, fname); + if (txtname == already_has_rel_mcount) { + result = 0; + file_updated = 0; + goto out; /* Nothing to be done; don't append! */ + } if (txtname && is_mcounted_section_name(txtname)) { + unsigned int recsym; uint_t recval = 0; - unsigned const recsym = find_secsym_ndx( - w(relhdr->sh_info), txtname, &recval, - &shdr0[symsec_sh_link = w(relhdr->sh_link)], - ehdr); + + symsec_sh_link = w(relhdr->sh_link); + result = find_secsym_ndx(w(relhdr->sh_info), txtname, + &recval, &recsym, + &shdr0[symsec_sh_link], + ehdr); + if (result) + goto out; rel_entsize = _w(relhdr->sh_entsize); mlocp = sift_rel_mcount(mlocp, @@ -543,13 +596,17 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) * This section is ignored by ftrace, but still * has mcount calls. Convert them to nops now. */ - nop_mcount(relhdr, ehdr, txtname); + if (nop_mcount(relhdr, ehdr, txtname) < 0) { + result = -1; + goto out; + } } } - if (mloc0 != mlocp) { - append_func(ehdr, shstr, mloc0, mlocp, mrel0, mrelp, - rel_entsize, symsec_sh_link); - } + if (!result && mloc0 != mlocp) + result = append_func(ehdr, shstr, mloc0, mlocp, mrel0, mrelp, + rel_entsize, symsec_sh_link); +out: free(mrel0); free(mloc0); + return result; } |