diff options
| author | Kirill A. Shutemov <kirill@shutemov.name> | 2008-10-15 22:02:39 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-16 11:21:38 -0700 |
| commit | bf2a9a39639b8b51377905397a5005f444e9a892 (patch) | |
| tree | 1919ad1abea804ce4cb1e7e8b1ac44b5b9a8f110 /include | |
| parent | 53112488bebe25c0f5f8a002470046c0fe9a6c61 (diff) | |
Allow recursion in binfmt_script and binfmt_misc
binfmt_script and binfmt_misc disallow recursion to avoid stack overflow
using sh_bang and misc_bang. It causes problem in some cases:
$ echo '#!/bin/ls' > /tmp/t0
$ echo '#!/tmp/t0' > /tmp/t1
$ echo '#!/tmp/t1' > /tmp/t2
$ chmod +x /tmp/t*
$ /tmp/t2
zsh: exec format error: /tmp/t2
Similar problem with binfmt_misc.
This patch introduces field 'recursion_depth' into struct linux_binprm to
track recursion level in binfmt_misc and binfmt_script. If recursion
level more then BINPRM_MAX_RECURSION it generates -ENOEXEC.
[akpm@linux-foundation.org: make linux_binprm.recursion_depth a uint]
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/binfmts.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h index 54980a3c760..7394b5b349f 100644 --- a/include/linux/binfmts.h +++ b/include/linux/binfmts.h @@ -39,6 +39,7 @@ struct linux_binprm{ #ifdef __alpha__ unsigned int taso:1; #endif + unsigned int recursion_depth; struct file * file; int e_uid, e_gid; kernel_cap_t cap_post_exec_permitted; @@ -61,6 +62,7 @@ struct linux_binprm{ #define BINPRM_FLAGS_EXECFD_BIT 1 #define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT) +#define BINPRM_MAX_RECURSION 4 /* * This structure defines the functions that are used to load the binary formats that |