Please don't post respins as replies, because our tooling will miss them there, and even humans may. Start a new thread instead. Next time :)
Elena Afanasova <eafanas...@gmail.com> writes: > Subject: [PATCH v2] elfload: use g_new/g_malloc and g_autofree > > Signed-off-by: Elena Afanasova <eafanas...@gmail.com> > --- > bsd-user/elfload.c | 79 ++++++++-------------------------------------- > 1 file changed, 14 insertions(+), 65 deletions(-) > > diff --git a/bsd-user/elfload.c b/bsd-user/elfload.c > index 32378af7b2..bc4be4c874 100644 > --- a/bsd-user/elfload.c > +++ b/bsd-user/elfload.c > @@ -838,7 +838,7 @@ static abi_ulong load_elf_interp(struct elfhdr * > interp_elf_ex, > int interpreter_fd, > abi_ulong *interp_load_addr) > { > - struct elf_phdr *elf_phdata = NULL; > + g_autofree struct elf_phdr *elf_phdata = NULL; > struct elf_phdr *eppnt; > abi_ulong load_addr = 0; > int load_addr_set = 0; > @@ -867,18 +867,13 @@ static abi_ulong load_elf_interp(struct elfhdr * > interp_elf_ex, > if (sizeof(struct elf_phdr) * interp_elf_ex->e_phnum > > TARGET_PAGE_SIZE) > return ~(abi_ulong)0UL; > > - elf_phdata = (struct elf_phdr *) > - malloc(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum); > - > - if (!elf_phdata) > - return ~((abi_ulong)0UL); > + elf_phdata = g_new(struct elf_phdr, interp_elf_ex->e_phnum); > > /* > * If the size of this structure has changed, then punt, since > * we will be doing the wrong thing. > */ > if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) { > - free(elf_phdata); > return ~((abi_ulong)0UL); > } > > @@ -891,7 +886,6 @@ static abi_ulong load_elf_interp(struct elfhdr * > interp_elf_ex, > if (retval < 0) { > perror("load_elf_interp"); > exit(-1); > - free (elf_phdata); > return retval; > } > #ifdef BSWAP_NEEDED > @@ -940,7 +934,6 @@ static abi_ulong load_elf_interp(struct elfhdr * > interp_elf_ex, > if (error == -1) { > /* Real error */ > close(interpreter_fd); > - free(elf_phdata); > return ~((abi_ulong)0UL); > } > > @@ -983,7 +976,6 @@ static abi_ulong load_elf_interp(struct elfhdr * > interp_elf_ex, > PROT_READ|PROT_WRITE|PROT_EXEC, > MAP_FIXED|MAP_PRIVATE|MAP_ANON, -1, 0); > } > - free(elf_phdata); > > *interp_load_addr = load_addr; > return ((abi_ulong) interp_elf_ex->e_entry) + load_addr; > @@ -1036,9 +1028,10 @@ static void load_symbols(struct elfhdr *hdr, int fd) > { > unsigned int i, nsyms; > struct elf_shdr sechdr, symtab, strtab; > - char *strings; > - struct syminfo *s; > - struct elf_sym *syms, *new_syms; > + g_autofree char *strings = NULL; > + g_autofree struct syminfo *s = NULL; > + g_autofree struct elf_sym *syms = NULL; > + struct elf_sym *new_syms; Note for later: @strings, @syminfo and @syms are freed on return. > > lseek(fd, hdr->e_shoff, SEEK_SET); > for (i = 0; i < hdr->e_shnum; i++) { > @@ -1064,24 +1057,12 @@ static void load_symbols(struct elfhdr *hdr, int fd) > > found: > /* Now know where the strtab and symtab are. Snarf them. */ > - s = malloc(sizeof(*s)); > - syms = malloc(symtab.sh_size); > - if (!syms) { > - free(s); > - return; > - } > - s->disas_strtab = strings = malloc(strtab.sh_size); > - if (!s->disas_strtab) { > - free(s); > - free(syms); > - return; > - } > + s = g_new(struct syminfo, 1); The smaller change would be s = g_malloc(sizeof(*s)); Matter of taste. > + syms = g_malloc(symtab.sh_size); > + s->disas_strtab = strings = g_new(char, strtab.sh_size); I'd prefer the simpler s->disas_strtab = strings = g_malloc(strtab.sh_size); Yes, it returns void * whereas g_new() returns char *, but the char * is vanishingly unlikely to catch actual bugs. > > lseek(fd, symtab.sh_offset, SEEK_SET); > if (read(fd, syms, symtab.sh_size) != symtab.sh_size) { > - free(s); > - free(syms); > - free(strings); > return; > } > > @@ -1113,22 +1094,13 @@ static void load_symbols(struct elfhdr *hdr, int fd) > that we threw away. Whether or not this has any effect on the > memory allocation depends on the malloc implementation and how > many symbols we managed to discard. */ > - new_syms = realloc(syms, nsyms * sizeof(*syms)); > - if (new_syms == NULL) { > - free(s); > - free(syms); > - free(strings); > - return; > - } > + new_syms = g_realloc(syms, nsyms * sizeof(*syms)); > syms = new_syms; > > qsort(syms, nsyms, sizeof(*syms), symcmp); > > lseek(fd, strtab.sh_offset, SEEK_SET); > if (read(fd, strings, strtab.sh_size) != strtab.sh_size) { > - free(s); > - free(syms); > - free(strings); > return; > } > s->disas_num_syms = nsyms; #if ELF_CLASS == ELFCLASS32 s->disas_symtab.elf32 = syms; s->lookup_symbol = (lookup_symbol_t)lookup_symbolxx; #else s->disas_symtab.elf64 = syms; s->lookup_symbol = (lookup_symbol_t)lookup_symbolxx; #endif s->next = syminfos; syminfos = s; @strings, @syminfo and @syms are freed here. s->disas_strtab, s->disas_symtab.elf{32,64}, s->next become dangling pointers. I'd expect this to blow up. Have you tested? } > @@ -1156,10 +1128,10 @@ int load_elf_binary(struct linux_binprm * bprm, > struct target_pt_regs * regs, > unsigned char ibcs2_interpreter; > int i; > struct elf_phdr * elf_ppnt; > - struct elf_phdr *elf_phdata; > + g_autofree struct elf_phdr *elf_phdata = NULL; > abi_ulong elf_bss, k, elf_brk; > int retval; > - char * elf_interpreter; > + g_autofree char *elf_interpreter = NULL; > abi_ulong elf_entry, interp_load_addr = 0; > abi_ulong start_code, end_code, start_data, end_data; > abi_ulong reloc_func_desc = 0; > @@ -1190,10 +1162,7 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > } > > /* Now read in all of the header information */ > - elf_phdata = (struct elf_phdr > *)malloc(elf_ex.e_phentsize*elf_ex.e_phnum); > - if (elf_phdata == NULL) { > - return -ENOMEM; > - } > + elf_phdata = g_new(struct elf_phdr, elf_ex.e_phnum); This assumes elf_ex.e_phentsize == sizeof(struct elf_phdr). Why is that true? > > retval = lseek(bprm->fd, elf_ex.e_phoff, SEEK_SET); > if(retval > 0) { > @@ -1204,7 +1173,6 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > if (retval < 0) { > perror("load_elf_binary"); > exit(-1); > - free (elf_phdata); > return -errno; > } > > @@ -1220,7 +1188,6 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > elf_brk = 0; > > > - elf_interpreter = NULL; > start_code = ~((abi_ulong)0UL); > end_code = 0; > start_data = 0; > @@ -1231,8 +1198,6 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > if (elf_ppnt->p_type == PT_INTERP) { > if ( elf_interpreter != NULL ) > { > - free (elf_phdata); > - free(elf_interpreter); > close(bprm->fd); > return -EINVAL; > } > @@ -1242,13 +1207,7 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > * is an a.out format binary > */ > > - elf_interpreter = (char *)malloc(elf_ppnt->p_filesz); > - > - if (elf_interpreter == NULL) { > - free (elf_phdata); > - close(bprm->fd); > - return -ENOMEM; > - } > + elf_interpreter = g_new(char, elf_ppnt->p_filesz); Again, I'd prefer the simpler elf_interpreter = g_malloc(elf_ppnt->p_filesz); > > retval = lseek(bprm->fd, elf_ppnt->p_offset, SEEK_SET); > if(retval >= 0) { > @@ -1298,8 +1257,6 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > if (retval < 0) { > perror("load_elf_binary3"); > exit(-1); > - free (elf_phdata); > - free(elf_interpreter); > close(bprm->fd); > return retval; > } > @@ -1323,8 +1280,6 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > } > > if (!interpreter_type) { > - free(elf_interpreter); > - free(elf_phdata); > close(bprm->fd); > return -ELIBBAD; > } > @@ -1346,8 +1301,6 @@ int load_elf_binary(struct linux_binprm * bprm, struct > target_pt_regs * regs, > } > } > if (!bprm->p) { > - free(elf_interpreter); > - free (elf_phdata); > close(bprm->fd); > return -E2BIG; > } > @@ -1486,18 +1439,14 @@ int load_elf_binary(struct linux_binprm * bprm, > struct target_pt_regs * regs, > reloc_func_desc = interp_load_addr; > > close(interpreter_fd); > - free(elf_interpreter); > > if (elf_entry == ~((abi_ulong)0UL)) { > printf("Unable to load interpreter\n"); > - free(elf_phdata); > exit(-1); > return 0; > } > } > > - free(elf_phdata); > - > if (qemu_log_enabled()) > load_symbols(&elf_ex, bprm->fd);