diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2008-04-22 13:11:59 +0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2008-04-25 17:23:53 +0400 |
| commit | fd8328be874f4190a811c58cd4778ec2c74d2c05 (patch) | |
| tree | b44ae8e99ce96a1a4739b04d4d1a23c40ab8b163 /fs/binfmt_elf.c | |
| parent | 6b335d9c80d7f3c2a3f6545f664ae9007a0f3821 (diff) | |
| download | linux-fd8328be874f4190a811c58cd4778ec2c74d2c05.tar.xz | |
[PATCH] sanitize handling of shared descriptor tables in failing execve()
* unshare_files() can fail; doing it after irreversible actions is wrong
and de_thread() is certainly irreversible.
* since we do it unconditionally anyway, we might as well do it in do_execve()
and save ourselves the PITA in binfmt handlers, etc.
* while we are at it, binfmt_som actually leaked files_struct on failure.
As a side benefit, unshare_files(), put_files_struct() and reset_files_struct()
become unexported.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/binfmt_elf.c')
| -rw-r--r-- | fs/binfmt_elf.c | 23 |
1 files changed, 1 insertions, 22 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 5e1a4fb5cacb..9924581df6f6 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -543,7 +543,6 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) unsigned long interp_load_addr = 0; unsigned long start_code, end_code, start_data, end_data; unsigned long reloc_func_desc = 0; - struct files_struct *files; int executable_stack = EXSTACK_DEFAULT; unsigned long def_flags = 0; struct { @@ -593,20 +592,9 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) goto out_free_ph; } - files = current->files; /* Refcounted so ok */ - retval = unshare_files(); - if (retval < 0) - goto out_free_ph; - if (files == current->files) { - put_files_struct(files); - files = NULL; - } - - /* exec will make our files private anyway, but for the a.out - loader stuff we need to do it earlier */ retval = get_unused_fd(); if (retval < 0) - goto out_free_fh; + goto out_free_ph; get_file(bprm->file); fd_install(elf_exec_fileno = retval, bprm->file); @@ -728,12 +716,6 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) if (retval) goto out_free_dentry; - /* Discard our unneeded old files struct */ - if (files) { - put_files_struct(files); - files = NULL; - } - /* OK, This is the point of no return */ current->flags &= ~PF_FORKNOEXEC; current->mm->def_flags = def_flags; @@ -1016,9 +998,6 @@ out_free_interp: kfree(elf_interpreter); out_free_file: sys_close(elf_exec_fileno); -out_free_fh: - if (files) - reset_files_struct(current, files); out_free_ph: kfree(elf_phdata); goto out; |