* [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
@ 2015-03-21 23:08 ` Taesoo Kim
0 siblings, 0 replies; 10+ messages in thread
From: Taesoo Kim @ 2015-03-21 23:08 UTC (permalink / raw)
To: sfrench-eUNUBHrolfbYtjvyW6yDsg,
linux-cifs-u79uwXL29TY76Z2rM5mHXA,
samba-technical-w/Ol4Ecudpl8XjKLYN78aQ,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: taesoo-/4noJB3qBVQ3uPMLIKxrzw, changwoo-/4noJB3qBVQ3uPMLIKxrzw,
sanidhya-/4noJB3qBVQ3uPMLIKxrzw, blee-/4noJB3qBVQ3uPMLIKxrzw,
csong84-/4noJB3qBVQ3uPMLIKxrzw, Taesoo Kim
For example, when mount opt is redundently specified
(e.g., "user=A,user=B,user=C"), kernel kept allocating new key/val
with kstrdup() and overwrite previous ptr (to be freed).
Althouhg mkfs.cifs in userspace performs a bit of sanitization
(e.g., forcing one user option), current implementation is not
robust. Other options such as iocharset and domainanme are similary
vulnerable.
Signed-off-by: Taesoo Kim <tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
fs/cifs/connect.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index d3aa999..4cb8450 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1599,6 +1599,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
pr_warn("CIFS: username too long\n");
goto cifs_parse_mount_err;
}
+
+ kfree(vol->username);
vol->username = kstrdup(string, GFP_KERNEL);
if (!vol->username)
goto cifs_parse_mount_err;
@@ -1700,6 +1702,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
goto cifs_parse_mount_err;
}
+ kfree(vol->domainname);
vol->domainname = kstrdup(string, GFP_KERNEL);
if (!vol->domainname) {
pr_warn("CIFS: no memory for domainname\n");
@@ -1731,6 +1734,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
}
if (strncasecmp(string, "default", 7) != 0) {
+ kfree(vol->iocharset);
vol->iocharset = kstrdup(string,
GFP_KERNEL);
if (!vol->iocharset) {
--
2.3.3
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
@ 2015-03-21 23:08 ` Taesoo Kim
0 siblings, 0 replies; 10+ messages in thread
From: Taesoo Kim @ 2015-03-21 23:08 UTC (permalink / raw)
To: sfrench, linux-cifs, samba-technical, linux-kernel
Cc: taesoo, changwoo, sanidhya, blee, csong84, Taesoo Kim
For example, when mount opt is redundently specified
(e.g., "user=A,user=B,user=C"), kernel kept allocating new key/val
with kstrdup() and overwrite previous ptr (to be freed).
Althouhg mkfs.cifs in userspace performs a bit of sanitization
(e.g., forcing one user option), current implementation is not
robust. Other options such as iocharset and domainanme are similary
vulnerable.
Signed-off-by: Taesoo Kim <tsgatesv@gmail.com>
---
fs/cifs/connect.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index d3aa999..4cb8450 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1599,6 +1599,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
pr_warn("CIFS: username too long\n");
goto cifs_parse_mount_err;
}
+
+ kfree(vol->username);
vol->username = kstrdup(string, GFP_KERNEL);
if (!vol->username)
goto cifs_parse_mount_err;
@@ -1700,6 +1702,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
goto cifs_parse_mount_err;
}
+ kfree(vol->domainname);
vol->domainname = kstrdup(string, GFP_KERNEL);
if (!vol->domainname) {
pr_warn("CIFS: no memory for domainname\n");
@@ -1731,6 +1734,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
}
if (strncasecmp(string, "default", 7) != 0) {
+ kfree(vol->iocharset);
vol->iocharset = kstrdup(string,
GFP_KERNEL);
if (!vol->iocharset) {
--
2.3.3
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
2015-03-21 23:08 ` Taesoo Kim
@ 2015-03-22 2:10 ` Scott Lovenberg
-1 siblings, 0 replies; 10+ messages in thread
From: Scott Lovenberg @ 2015-03-22 2:10 UTC (permalink / raw)
To: Taesoo Kim
Cc: sfrench-eUNUBHrolfbYtjvyW6yDsg, linux-cifs,
samba-technical-w/Ol4Ecudpl8XjKLYN78aQ, LKML,
taesoo-/4noJB3qBVQ3uPMLIKxrzw, changwoo-/4noJB3qBVQ3uPMLIKxrzw,
sanidhya-/4noJB3qBVQ3uPMLIKxrzw, blee-/4noJB3qBVQ3uPMLIKxrzw,
csong84-/4noJB3qBVQ3uPMLIKxrzw
On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Althouhg mkfs.cifs in userspace performs a bit of sanitization
> (e.g., forcing one user option), current implementation is not
> robust. Other options such as iocharset and domainanme are similary
> vulnerable.
>
I assume you mean mount.cifs? :-) Anyways, good catch.
--
Peace and Blessings,
-Scott.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
@ 2015-03-22 2:10 ` Scott Lovenberg
0 siblings, 0 replies; 10+ messages in thread
From: Scott Lovenberg @ 2015-03-22 2:10 UTC (permalink / raw)
To: Taesoo Kim
Cc: sfrench, linux-cifs, samba-technical, LKML, taesoo, changwoo,
sanidhya, blee, csong84
On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv@gmail.com> wrote:
> Althouhg mkfs.cifs in userspace performs a bit of sanitization
> (e.g., forcing one user option), current implementation is not
> robust. Other options such as iocharset and domainanme are similary
> vulnerable.
>
I assume you mean mount.cifs? :-) Anyways, good catch.
--
Peace and Blessings,
-Scott.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
2015-03-22 2:10 ` Scott Lovenberg
@ 2015-03-22 3:23 ` Taesoo Kim
-1 siblings, 0 replies; 10+ messages in thread
From: Taesoo Kim @ 2015-03-22 3:23 UTC (permalink / raw)
To: Scott Lovenberg
Cc: Taesoo Kim, sfrench-eUNUBHrolfbYtjvyW6yDsg, linux-cifs,
samba-technical-w/Ol4Ecudpl8XjKLYN78aQ, LKML,
changwoo-/4noJB3qBVQ3uPMLIKxrzw, sanidhya-/4noJB3qBVQ3uPMLIKxrzw,
blee-/4noJB3qBVQ3uPMLIKxrzw, csong84-/4noJB3qBVQ3uPMLIKxrzw
On 03/21/15 at 09:10pm, Scott Lovenberg wrote:
> On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > Althouhg mkfs.cifs in userspace performs a bit of sanitization
> > (e.g., forcing one user option), current implementation is not
> > robust. Other options such as iocharset and domainanme are similary
> > vulnerable.
> >
>
> I assume you mean mount.cifs? :-) Anyways, good catch.
Right. FYI, I've tried mangling password field (e.g., pass=a,user=A
&c); Skimming through the code (just a few minutes), there are a few
potential places that don't sanitize its string, unlike passwd. But
don't have much time to play with for now :)
Thanks,
Taesoo
> --
> Peace and Blessings,
> -Scott.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
@ 2015-03-22 3:23 ` Taesoo Kim
0 siblings, 0 replies; 10+ messages in thread
From: Taesoo Kim @ 2015-03-22 3:23 UTC (permalink / raw)
To: Scott Lovenberg
Cc: Taesoo Kim, sfrench, linux-cifs, samba-technical, LKML, changwoo,
sanidhya, blee, csong84
On 03/21/15 at 09:10pm, Scott Lovenberg wrote:
> On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv@gmail.com> wrote:
>
> > Althouhg mkfs.cifs in userspace performs a bit of sanitization
> > (e.g., forcing one user option), current implementation is not
> > robust. Other options such as iocharset and domainanme are similary
> > vulnerable.
> >
>
> I assume you mean mount.cifs? :-) Anyways, good catch.
Right. FYI, I've tried mangling password field (e.g., pass=a,user=A
&c); Skimming through the code (just a few minutes), there are a few
potential places that don't sanitize its string, unlike passwd. But
don't have much time to play with for now :)
Thanks,
Taesoo
> --
> Peace and Blessings,
> -Scott.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
2015-03-22 3:23 ` Taesoo Kim
@ 2015-03-22 3:54 ` Scott Lovenberg
-1 siblings, 0 replies; 10+ messages in thread
From: Scott Lovenberg @ 2015-03-22 3:54 UTC (permalink / raw)
To: Taesoo Kim
Cc: Taesoo Kim, sfrench-eUNUBHrolfbYtjvyW6yDsg, linux-cifs,
samba-technical-w/Ol4Ecudpl8XjKLYN78aQ, LKML,
changwoo-/4noJB3qBVQ3uPMLIKxrzw, sanidhya-/4noJB3qBVQ3uPMLIKxrzw,
blee-/4noJB3qBVQ3uPMLIKxrzw, csong84-/4noJB3qBVQ3uPMLIKxrzw
On Sat, Mar 21, 2015 at 10:23 PM, Taesoo Kim <taesoo-/4noJB3qBVQ3uPMLIKxrzw@public.gmane.org> wrote:
> On 03/21/15 at 09:10pm, Scott Lovenberg wrote:
>> On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>
>> > Althouhg mkfs.cifs in userspace performs a bit of sanitization
>> > (e.g., forcing one user option), current implementation is not
>> > robust. Other options such as iocharset and domainanme are similary
>> > vulnerable.
>> >
>>
>> I assume you mean mount.cifs? :-) Anyways, good catch.
>
> Right. FYI, I've tried mangling password field (e.g., pass=a,user=A
> &c); Skimming through the code (just a few minutes), there are a few
> potential places that don't sanitize its string, unlike passwd. But
> don't have much time to play with for now :)
>
> Thanks,
> Taesoo
>
>> --
>> Peace and Blessings,
>> -Scott.
Without even looking at the code, I can tell you that's probably my
fault if you're talking about the code in mount.cifs. I was pretty
paranoid about the password field but not so paranoid about the other
parameters. I'll take a look late tonight or some time tomorrow and
try to patch over my shame. :)
--
Peace and Blessings,
-Scott.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
@ 2015-03-22 3:54 ` Scott Lovenberg
0 siblings, 0 replies; 10+ messages in thread
From: Scott Lovenberg @ 2015-03-22 3:54 UTC (permalink / raw)
To: Taesoo Kim
Cc: Taesoo Kim, sfrench, linux-cifs, samba-technical, LKML, changwoo,
sanidhya, blee, csong84
On Sat, Mar 21, 2015 at 10:23 PM, Taesoo Kim <taesoo@gatech.edu> wrote:
> On 03/21/15 at 09:10pm, Scott Lovenberg wrote:
>> On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv@gmail.com> wrote:
>>
>> > Althouhg mkfs.cifs in userspace performs a bit of sanitization
>> > (e.g., forcing one user option), current implementation is not
>> > robust. Other options such as iocharset and domainanme are similary
>> > vulnerable.
>> >
>>
>> I assume you mean mount.cifs? :-) Anyways, good catch.
>
> Right. FYI, I've tried mangling password field (e.g., pass=a,user=A
> &c); Skimming through the code (just a few minutes), there are a few
> potential places that don't sanitize its string, unlike passwd. But
> don't have much time to play with for now :)
>
> Thanks,
> Taesoo
>
>> --
>> Peace and Blessings,
>> -Scott.
Without even looking at the code, I can tell you that's probably my
fault if you're talking about the code in mount.cifs. I was pretty
paranoid about the password field but not so paranoid about the other
parameters. I'll take a look late tonight or some time tomorrow and
try to patch over my shame. :)
--
Peace and Blessings,
-Scott.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
2015-03-21 23:08 ` Taesoo Kim
@ 2015-03-24 4:43 ` Steve French
-1 siblings, 0 replies; 10+ messages in thread
From: Steve French @ 2015-03-24 4:43 UTC (permalink / raw)
To: Taesoo Kim
Cc: Steve French, linux-cifs-u79uwXL29TY76Z2rM5mHXA, samba-technical,
LKML, taesoo-/4noJB3qBVQ3uPMLIKxrzw,
changwoo-/4noJB3qBVQ3uPMLIKxrzw, sanidhya-/4noJB3qBVQ3uPMLIKxrzw,
blee-/4noJB3qBVQ3uPMLIKxrzw, csong84-/4noJB3qBVQ3uPMLIKxrzw,
Scott Lovenberg
Nice catch.
Merged into cifs-2.6.git for-next
On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> For example, when mount opt is redundently specified
> (e.g., "user=A,user=B,user=C"), kernel kept allocating new key/val
> with kstrdup() and overwrite previous ptr (to be freed).
>
> Althouhg mkfs.cifs in userspace performs a bit of sanitization
> (e.g., forcing one user option), current implementation is not
> robust. Other options such as iocharset and domainanme are similary
> vulnerable.
>
> Signed-off-by: Taesoo Kim <tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> ---
> fs/cifs/connect.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index d3aa999..4cb8450 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -1599,6 +1599,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> pr_warn("CIFS: username too long\n");
> goto cifs_parse_mount_err;
> }
> +
> + kfree(vol->username);
> vol->username = kstrdup(string, GFP_KERNEL);
> if (!vol->username)
> goto cifs_parse_mount_err;
> @@ -1700,6 +1702,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> goto cifs_parse_mount_err;
> }
>
> + kfree(vol->domainname);
> vol->domainname = kstrdup(string, GFP_KERNEL);
> if (!vol->domainname) {
> pr_warn("CIFS: no memory for domainname\n");
> @@ -1731,6 +1734,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> }
>
> if (strncasecmp(string, "default", 7) != 0) {
> + kfree(vol->iocharset);
> vol->iocharset = kstrdup(string,
> GFP_KERNEL);
> if (!vol->iocharset) {
> --
> 2.3.3
>
--
Thanks,
Steve
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts
@ 2015-03-24 4:43 ` Steve French
0 siblings, 0 replies; 10+ messages in thread
From: Steve French @ 2015-03-24 4:43 UTC (permalink / raw)
To: Taesoo Kim
Cc: Steve French, linux-cifs, samba-technical, LKML, taesoo,
changwoo, sanidhya, blee, csong84, Scott Lovenberg
Nice catch.
Merged into cifs-2.6.git for-next
On Sat, Mar 21, 2015 at 6:08 PM, Taesoo Kim <tsgatesv@gmail.com> wrote:
> For example, when mount opt is redundently specified
> (e.g., "user=A,user=B,user=C"), kernel kept allocating new key/val
> with kstrdup() and overwrite previous ptr (to be freed).
>
> Althouhg mkfs.cifs in userspace performs a bit of sanitization
> (e.g., forcing one user option), current implementation is not
> robust. Other options such as iocharset and domainanme are similary
> vulnerable.
>
> Signed-off-by: Taesoo Kim <tsgatesv@gmail.com>
> ---
> fs/cifs/connect.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index d3aa999..4cb8450 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -1599,6 +1599,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> pr_warn("CIFS: username too long\n");
> goto cifs_parse_mount_err;
> }
> +
> + kfree(vol->username);
> vol->username = kstrdup(string, GFP_KERNEL);
> if (!vol->username)
> goto cifs_parse_mount_err;
> @@ -1700,6 +1702,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> goto cifs_parse_mount_err;
> }
>
> + kfree(vol->domainname);
> vol->domainname = kstrdup(string, GFP_KERNEL);
> if (!vol->domainname) {
> pr_warn("CIFS: no memory for domainname\n");
> @@ -1731,6 +1734,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> }
>
> if (strncasecmp(string, "default", 7) != 0) {
> + kfree(vol->iocharset);
> vol->iocharset = kstrdup(string,
> GFP_KERNEL);
> if (!vol->iocharset) {
> --
> 2.3.3
>
--
Thanks,
Steve
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2015-03-24 4:44 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-03-21 23:08 [PATCH 1/1] cifs: potential memory leaks when parsing mnt opts Taesoo Kim
2015-03-21 23:08 ` Taesoo Kim
[not found] ` <1426979310-31201-1-git-send-email-tsgatesv-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2015-03-22 2:10 ` Scott Lovenberg
2015-03-22 2:10 ` Scott Lovenberg
[not found] ` <CAFB9KM3==40uUXxxOD_CD09zFPj3Fmr-Brt7x4SZj86NTf3_vg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-03-22 3:23 ` Taesoo Kim
2015-03-22 3:23 ` Taesoo Kim
[not found] ` <20150322032340.GD5170-Q1ymHw66ZoYdnm+yROfE0A@public.gmane.org>
2015-03-22 3:54 ` Scott Lovenberg
2015-03-22 3:54 ` Scott Lovenberg
2015-03-24 4:43 ` Steve French
2015-03-24 4:43 ` Steve French
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