blob: 3e092c0dfe61ce811a063f21b937bf4381286dbc (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
From: Marcel Holtmann <marcel@holtmann.org>
Date: Fri, 17 Aug 2007 19:47:58 +0000 (+0200)
Subject: Reset current->pdeath_signal on SUID binary execution
X-Git-Tag: v2.6.23-rc4~134
X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=d2d56c5f51028cb9f3d800882eb6f4cbd3f9099f
Reset current->pdeath_signal on SUID binary execution
This fixes a vulnerability in the "parent process death signal"
implementation discoverd by Wojciech Purczynski of COSEINC PTE Ltd.
and iSEC Security Research.
http://marc.info/?l=bugtraq&m=118711306802632&w=2
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
Backported to Debian's 2.6.18 by dann frazier <dannf@debian.org>
diff -urpN linux-source-2.6.18.orig/fs/exec.c linux-source-2.6.18/fs/exec.c
--- linux-source-2.6.18.orig/fs/exec.c 2007-09-05 14:11:16.000000000 -0600
+++ linux-source-2.6.18/fs/exec.c 2007-09-05 14:17:02.000000000 -0600
@@ -883,9 +883,12 @@ int flush_old_exec(struct linux_binprm *
*/
current->mm->task_size = TASK_SIZE;
- if (bprm->e_uid != current->euid || bprm->e_gid != current->egid ||
- file_permission(bprm->file, MAY_READ) ||
- (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)) {
+ if (bprm->e_uid != current->euid || bprm->e_gid != current->egid) {
+ suid_keys(current);
+ current->mm->dumpable = suid_dumpable;
+ current->pdeath_signal = 0;
+ } else if (file_permission(bprm->file, MAY_READ) ||
+ (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)) {
suid_keys(current);
current->mm->dumpable = suid_dumpable;
}
@@ -977,8 +980,10 @@ void compute_creds(struct linux_binprm *
{
int unsafe;
- if (bprm->e_uid != current->uid)
+ if (bprm->e_uid != current->uid) {
suid_keys(current);
+ current->pdeath_signal = 0;
+ }
exec_keys(current);
task_lock(current);
|
GitWeb
