From 0693ffebcfe5ac7b31f63ad54587007f7d96fb7b Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Mon, 6 Apr 2020 20:11:29 -0700 Subject: [PATCH] fs/binfmt_elf.c: allocate less for static executable PT_INTERP ELF header can be spared if executable is static. Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Link: http://lkml.kernel.org/r/20200219185012.GB4871@avx2 Signed-off-by: Linus Torvalds --- fs/binfmt_elf.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 3cb888cb2b2b..a3a9429ef1d2 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -699,17 +699,11 @@ static int load_elf_binary(struct linux_binprm *bprm) unsigned long reloc_func_desc __maybe_unused = 0; int executable_stack = EXSTACK_DEFAULT; struct elfhdr *elf_ex = (struct elfhdr *)bprm->buf; - struct elfhdr *interp_elf_ex; + struct elfhdr *interp_elf_ex = NULL; struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE; struct mm_struct *mm; struct pt_regs *regs; - interp_elf_ex = kmalloc(sizeof(*interp_elf_ex), GFP_KERNEL); - if (!interp_elf_ex) { - retval = -ENOMEM; - goto out_ret; - } - retval = -ENOEXEC; /* First of all, some simple consistency checks */ if (memcmp(elf_ex->e_ident, ELFMAG, SELFMAG) != 0) @@ -769,6 +763,12 @@ static int load_elf_binary(struct linux_binprm *bprm) */ would_dump(bprm, interpreter); + interp_elf_ex = kmalloc(sizeof(*interp_elf_ex), GFP_KERNEL); + if (!interp_elf_ex) { + retval = -ENOMEM; + goto out_free_ph; + } + /* Get the exec headers */ retval = elf_read(interpreter, interp_elf_ex, sizeof(*interp_elf_ex), 0); @@ -1074,6 +1074,8 @@ static int load_elf_binary(struct linux_binprm *bprm) allow_write_access(interpreter); fput(interpreter); + + kfree(interp_elf_ex); } else { elf_entry = e_entry; if (BAD_ADDR(elf_entry)) { @@ -1152,12 +1154,11 @@ static int load_elf_binary(struct linux_binprm *bprm) start_thread(regs, elf_entry, bprm->p); retval = 0; out: - kfree(interp_elf_ex); -out_ret: return retval; /* error cleanup */ out_free_dentry: + kfree(interp_elf_ex); kfree(interp_elf_phdata); allow_write_access(interpreter); if (interpreter) -- GitLab