Re: proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
Andrew Morton wrote:
> On Thu, 06 Dec 2007 09:21:53 +0100 Giacomo Catenazzi <[EMAIL PROTECTED]>
> wrote:
>
>> Andrew Morton wrote:
>>> On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List
>>> wrote:
>>>
Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39
Author: Eric W. Biederman <[EMAIL PROTECTED]>
AuthorDate: Sun Dec 2 00:33:17 2007 +1100
Committer: Herbert Xu <[EMAIL PROTECTED]>
CommitDate: Sun Dec 2 00:33:17 2007 +1100
[NETNS]: Fix /proc/net breakage
Well I clearly goofed when I added the initial network namespace
support
for /proc/net. Currently things work but there are odd details
visible to
user space, even when we have a single network namespace.
Since we do not cache proc_dir_entry dentries at the moment we can just
modify ->lookup to return a different directory inode depending on the
network namespace of the process looking at /proc/net, replacing the
current technique of using a magic and fragile follow_link method.
To accomplish that this patch:
- introduces a shadow_proc method to allow different dentries to
be returned from proc_lookup.
- Removes the old /proc/net follow_link magic
- Fixes a weakness in our not caching of proc generic dentries.
As shadow_proc uses a task struct to decided which dentry to return we
can
go back later and fix the proc generic caching without modifying any
code
that uses the shadow_proc method.
>>> This patch caused the binfmt_misc regression reported in
>>> http://bugzilla.kernel.org/show_bug.cgi?id=9504
>> This patch also doesn't allow to mount /proc/bus/usb
>>
>
> Does Denis's patch fix it?
Yes, this patch solve the problem.
Tested-by: Giacomo Catenazzi <[EMAIL PROTECTED]>
ciao
cate
>
> Thanks.
>
>
> From: "Denis V. Lunev" <[EMAIL PROTECTED]>
>
> /proc/sys/fs/binfmt_misc dentry disappeared during d_revalidate.
> d_revalidate only dentries from shadowed one and below.
> http://bugzilla.kernel.org/show_bug.cgi?id=9504
>
> Cc: Eric W. Biederman <[EMAIL PROTECTED]>
> Cc: Marcus Better <[EMAIL PROTECTED]>
> Signed-off-by: Denis V. Lunev <[EMAIL PROTECTED]>
> Cc: Marcus Better <[EMAIL PROTECTED]>
> Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
> ---
>
> fs/proc/generic.c | 14 --
> 1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff -puN fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
> fs/proc/generic.c
> --- a/fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
> +++ a/fs/proc/generic.c
> @@ -380,12 +380,17 @@ static int proc_revalidate_dentry(struct
> return 0;
> }
>
> -static struct dentry_operations proc_dentry_operations =
> +static struct dentry_operations proc_dentry_shadow_operations =
> {
> .d_delete = proc_delete_dentry,
> .d_revalidate = proc_revalidate_dentry,
> };
>
> +static struct dentry_operations proc_dentry_operations =
> +{
> + .d_delete = proc_delete_dentry,
> +};
> +
> /*
> * Don't create negative dentries here, return -ENOENT by hand
> * instead.
> @@ -394,6 +399,7 @@ struct dentry *proc_lookup(struct inode
> {
> struct inode *inode = NULL;
> struct proc_dir_entry * de;
> + int use_shadow = 0;
> int error = -ENOENT;
>
> lock_kernel();
> @@ -406,8 +412,10 @@ struct dentry *proc_lookup(struct inode
> if (!memcmp(dentry->d_name.name, de->name,
> de->namelen)) {
> unsigned int ino;
>
> - if (de->shadow_proc)
> + if (de->shadow_proc) {
> de = de->shadow_proc(current, de);
> + use_shadow = 1;
> + }
> ino = de->low_ino;
> de_get(de);
> spin_unlock(_subdir_lock);
> @@ -423,6 +431,8 @@ struct dentry *proc_lookup(struct inode
>
> if (inode) {
> dentry->d_op = _dentry_operations;
> + dentry->d_op = use_shadow ?
> + _dentry_shadow_operations : dentry->d_parent->d_op;
> d_add(dentry, inode);
> return NULL;
> }
> _
>
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Re: proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
Giacomo Catenazzi <[EMAIL PROTECTED]> writes: > Andrew Morton wrote: >> On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List > wrote: >> >>> Gitweb: > http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 >>> Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 >>> Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39 >>> Author: Eric W. Biederman <[EMAIL PROTECTED]> >>> AuthorDate: Sun Dec 2 00:33:17 2007 +1100 >>> Committer: Herbert Xu <[EMAIL PROTECTED]> >>> CommitDate: Sun Dec 2 00:33:17 2007 +1100 >>> >>> [NETNS]: Fix /proc/net breakage >>> >>> Well I clearly goofed when I added the initial network namespace support >>> for /proc/net. Currently things work but there are odd details visible to >>> user space, even when we have a single network namespace. >>> >>> Since we do not cache proc_dir_entry dentries at the moment we can just >>> modify ->lookup to return a different directory inode depending on the >>> network namespace of the process looking at /proc/net, replacing the >>> current technique of using a magic and fragile follow_link method. >>> >>> To accomplish that this patch: >>> - introduces a shadow_proc method to allow different dentries to >>> be returned from proc_lookup. >>> - Removes the old /proc/net follow_link magic >>> - Fixes a weakness in our not caching of proc generic dentries. >>> >>> As shadow_proc uses a task struct to decided which dentry to return we can >>> go back later and fix the proc generic caching without modifying any code >>> that uses the shadow_proc method. >> >> This patch caused the binfmt_misc regression reported in >> http://bugzilla.kernel.org/show_bug.cgi?id=9504 > > This patch also doesn't allow to mount /proc/bus/usb Agreed. Strictly speaking the mounts work but we just can't find them. It is equally bad either way. Eric -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
On Thu, 06 Dec 2007 09:21:53 +0100 Giacomo Catenazzi <[EMAIL PROTECTED]> wrote:
> Andrew Morton wrote:
> > On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List
> > wrote:
> >
> >> Gitweb:
> >> http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
> >> Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
> >> Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39
> >> Author: Eric W. Biederman <[EMAIL PROTECTED]>
> >> AuthorDate: Sun Dec 2 00:33:17 2007 +1100
> >> Committer: Herbert Xu <[EMAIL PROTECTED]>
> >> CommitDate: Sun Dec 2 00:33:17 2007 +1100
> >>
> >> [NETNS]: Fix /proc/net breakage
> >>
> >> Well I clearly goofed when I added the initial network namespace
> >> support
> >> for /proc/net. Currently things work but there are odd details
> >> visible to
> >> user space, even when we have a single network namespace.
> >>
> >> Since we do not cache proc_dir_entry dentries at the moment we can just
> >> modify ->lookup to return a different directory inode depending on the
> >> network namespace of the process looking at /proc/net, replacing the
> >> current technique of using a magic and fragile follow_link method.
> >>
> >> To accomplish that this patch:
> >> - introduces a shadow_proc method to allow different dentries to
> >> be returned from proc_lookup.
> >> - Removes the old /proc/net follow_link magic
> >> - Fixes a weakness in our not caching of proc generic dentries.
> >>
> >> As shadow_proc uses a task struct to decided which dentry to return we
> >> can
> >> go back later and fix the proc generic caching without modifying any
> >> code
> >> that uses the shadow_proc method.
> >
> > This patch caused the binfmt_misc regression reported in
> > http://bugzilla.kernel.org/show_bug.cgi?id=9504
>
> This patch also doesn't allow to mount /proc/bus/usb
>
Does Denis's patch fix it?
Thanks.
From: "Denis V. Lunev" <[EMAIL PROTECTED]>
/proc/sys/fs/binfmt_misc dentry disappeared during d_revalidate.
d_revalidate only dentries from shadowed one and below.
http://bugzilla.kernel.org/show_bug.cgi?id=9504
Cc: Eric W. Biederman <[EMAIL PROTECTED]>
Cc: Marcus Better <[EMAIL PROTECTED]>
Signed-off-by: Denis V. Lunev <[EMAIL PROTECTED]>
Cc: Marcus Better <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---
fs/proc/generic.c | 14 --
1 file changed, 12 insertions(+), 2 deletions(-)
diff -puN fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
fs/proc/generic.c
--- a/fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
+++ a/fs/proc/generic.c
@@ -380,12 +380,17 @@ static int proc_revalidate_dentry(struct
return 0;
}
-static struct dentry_operations proc_dentry_operations =
+static struct dentry_operations proc_dentry_shadow_operations =
{
.d_delete = proc_delete_dentry,
.d_revalidate = proc_revalidate_dentry,
};
+static struct dentry_operations proc_dentry_operations =
+{
+ .d_delete = proc_delete_dentry,
+};
+
/*
* Don't create negative dentries here, return -ENOENT by hand
* instead.
@@ -394,6 +399,7 @@ struct dentry *proc_lookup(struct inode
{
struct inode *inode = NULL;
struct proc_dir_entry * de;
+ int use_shadow = 0;
int error = -ENOENT;
lock_kernel();
@@ -406,8 +412,10 @@ struct dentry *proc_lookup(struct inode
if (!memcmp(dentry->d_name.name, de->name,
de->namelen)) {
unsigned int ino;
- if (de->shadow_proc)
+ if (de->shadow_proc) {
de = de->shadow_proc(current, de);
+ use_shadow = 1;
+ }
ino = de->low_ino;
de_get(de);
spin_unlock(_subdir_lock);
@@ -423,6 +431,8 @@ struct dentry *proc_lookup(struct inode
if (inode) {
dentry->d_op = _dentry_operations;
+ dentry->d_op = use_shadow ?
+ _dentry_shadow_operations : dentry->d_parent->d_op;
d_add(dentry, inode);
return NULL;
}
_
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proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
Andrew Morton wrote: > On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List > wrote: > >> Gitweb: >> http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 >> Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 >> Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39 >> Author: Eric W. Biederman <[EMAIL PROTECTED]> >> AuthorDate: Sun Dec 2 00:33:17 2007 +1100 >> Committer: Herbert Xu <[EMAIL PROTECTED]> >> CommitDate: Sun Dec 2 00:33:17 2007 +1100 >> >> [NETNS]: Fix /proc/net breakage >> >> Well I clearly goofed when I added the initial network namespace support >> for /proc/net. Currently things work but there are odd details visible >> to >> user space, even when we have a single network namespace. >> >> Since we do not cache proc_dir_entry dentries at the moment we can just >> modify ->lookup to return a different directory inode depending on the >> network namespace of the process looking at /proc/net, replacing the >> current technique of using a magic and fragile follow_link method. >> >> To accomplish that this patch: >> - introduces a shadow_proc method to allow different dentries to >> be returned from proc_lookup. >> - Removes the old /proc/net follow_link magic >> - Fixes a weakness in our not caching of proc generic dentries. >> >> As shadow_proc uses a task struct to decided which dentry to return we >> can >> go back later and fix the proc generic caching without modifying any code >> that uses the shadow_proc method. > > This patch caused the binfmt_misc regression reported in > http://bugzilla.kernel.org/show_bug.cgi?id=9504 This patch also doesn't allow to mount /proc/bus/usb ciao cate -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
Andrew Morton wrote: On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List linux-kernel@vger.kernel.org wrote: Gitweb: http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39 Author: Eric W. Biederman [EMAIL PROTECTED] AuthorDate: Sun Dec 2 00:33:17 2007 +1100 Committer: Herbert Xu [EMAIL PROTECTED] CommitDate: Sun Dec 2 00:33:17 2007 +1100 [NETNS]: Fix /proc/net breakage Well I clearly goofed when I added the initial network namespace support for /proc/net. Currently things work but there are odd details visible to user space, even when we have a single network namespace. Since we do not cache proc_dir_entry dentries at the moment we can just modify -lookup to return a different directory inode depending on the network namespace of the process looking at /proc/net, replacing the current technique of using a magic and fragile follow_link method. To accomplish that this patch: - introduces a shadow_proc method to allow different dentries to be returned from proc_lookup. - Removes the old /proc/net follow_link magic - Fixes a weakness in our not caching of proc generic dentries. As shadow_proc uses a task struct to decided which dentry to return we can go back later and fix the proc generic caching without modifying any code that uses the shadow_proc method. This patch caused the binfmt_misc regression reported in http://bugzilla.kernel.org/show_bug.cgi?id=9504 This patch also doesn't allow to mount /proc/bus/usb ciao cate -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
On Thu, 06 Dec 2007 09:21:53 +0100 Giacomo Catenazzi [EMAIL PROTECTED] wrote:
Andrew Morton wrote:
On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List
linux-kernel@vger.kernel.org wrote:
Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39
Author: Eric W. Biederman [EMAIL PROTECTED]
AuthorDate: Sun Dec 2 00:33:17 2007 +1100
Committer: Herbert Xu [EMAIL PROTECTED]
CommitDate: Sun Dec 2 00:33:17 2007 +1100
[NETNS]: Fix /proc/net breakage
Well I clearly goofed when I added the initial network namespace
support
for /proc/net. Currently things work but there are odd details
visible to
user space, even when we have a single network namespace.
Since we do not cache proc_dir_entry dentries at the moment we can just
modify -lookup to return a different directory inode depending on the
network namespace of the process looking at /proc/net, replacing the
current technique of using a magic and fragile follow_link method.
To accomplish that this patch:
- introduces a shadow_proc method to allow different dentries to
be returned from proc_lookup.
- Removes the old /proc/net follow_link magic
- Fixes a weakness in our not caching of proc generic dentries.
As shadow_proc uses a task struct to decided which dentry to return we
can
go back later and fix the proc generic caching without modifying any
code
that uses the shadow_proc method.
This patch caused the binfmt_misc regression reported in
http://bugzilla.kernel.org/show_bug.cgi?id=9504
This patch also doesn't allow to mount /proc/bus/usb
Does Denis's patch fix it?
Thanks.
From: Denis V. Lunev [EMAIL PROTECTED]
/proc/sys/fs/binfmt_misc dentry disappeared during d_revalidate.
d_revalidate only dentries from shadowed one and below.
http://bugzilla.kernel.org/show_bug.cgi?id=9504
Cc: Eric W. Biederman [EMAIL PROTECTED]
Cc: Marcus Better [EMAIL PROTECTED]
Signed-off-by: Denis V. Lunev [EMAIL PROTECTED]
Cc: Marcus Better [EMAIL PROTECTED]
Signed-off-by: Andrew Morton [EMAIL PROTECTED]
---
fs/proc/generic.c | 14 --
1 file changed, 12 insertions(+), 2 deletions(-)
diff -puN fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
fs/proc/generic.c
--- a/fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
+++ a/fs/proc/generic.c
@@ -380,12 +380,17 @@ static int proc_revalidate_dentry(struct
return 0;
}
-static struct dentry_operations proc_dentry_operations =
+static struct dentry_operations proc_dentry_shadow_operations =
{
.d_delete = proc_delete_dentry,
.d_revalidate = proc_revalidate_dentry,
};
+static struct dentry_operations proc_dentry_operations =
+{
+ .d_delete = proc_delete_dentry,
+};
+
/*
* Don't create negative dentries here, return -ENOENT by hand
* instead.
@@ -394,6 +399,7 @@ struct dentry *proc_lookup(struct inode
{
struct inode *inode = NULL;
struct proc_dir_entry * de;
+ int use_shadow = 0;
int error = -ENOENT;
lock_kernel();
@@ -406,8 +412,10 @@ struct dentry *proc_lookup(struct inode
if (!memcmp(dentry-d_name.name, de-name,
de-namelen)) {
unsigned int ino;
- if (de-shadow_proc)
+ if (de-shadow_proc) {
de = de-shadow_proc(current, de);
+ use_shadow = 1;
+ }
ino = de-low_ino;
de_get(de);
spin_unlock(proc_subdir_lock);
@@ -423,6 +431,8 @@ struct dentry *proc_lookup(struct inode
if (inode) {
dentry-d_op = proc_dentry_operations;
+ dentry-d_op = use_shadow ?
+ proc_dentry_shadow_operations : dentry-d_parent-d_op;
d_add(dentry, inode);
return NULL;
}
_
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Please read the FAQ at http://www.tux.org/lkml/
Re: proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
Giacomo Catenazzi [EMAIL PROTECTED] writes: Andrew Morton wrote: On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List linux-kernel@vger.kernel.org wrote: Gitweb: http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416 Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39 Author: Eric W. Biederman [EMAIL PROTECTED] AuthorDate: Sun Dec 2 00:33:17 2007 +1100 Committer: Herbert Xu [EMAIL PROTECTED] CommitDate: Sun Dec 2 00:33:17 2007 +1100 [NETNS]: Fix /proc/net breakage Well I clearly goofed when I added the initial network namespace support for /proc/net. Currently things work but there are odd details visible to user space, even when we have a single network namespace. Since we do not cache proc_dir_entry dentries at the moment we can just modify -lookup to return a different directory inode depending on the network namespace of the process looking at /proc/net, replacing the current technique of using a magic and fragile follow_link method. To accomplish that this patch: - introduces a shadow_proc method to allow different dentries to be returned from proc_lookup. - Removes the old /proc/net follow_link magic - Fixes a weakness in our not caching of proc generic dentries. As shadow_proc uses a task struct to decided which dentry to return we can go back later and fix the proc generic caching without modifying any code that uses the shadow_proc method. This patch caused the binfmt_misc regression reported in http://bugzilla.kernel.org/show_bug.cgi?id=9504 This patch also doesn't allow to mount /proc/bus/usb Agreed. Strictly speaking the mounts work but we just can't find them. It is equally bad either way. Eric -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: proc/bus.usb regression in : [NETNS]: Fix /proc/net breakage
Andrew Morton wrote:
On Thu, 06 Dec 2007 09:21:53 +0100 Giacomo Catenazzi [EMAIL PROTECTED]
wrote:
Andrew Morton wrote:
On Mon, 3 Dec 2007 19:00:25 GMT Linux Kernel Mailing List
linux-kernel@vger.kernel.org wrote:
Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Commit: 2b1e300a9dfc3196ccddf6f1d74b91b7af55e416
Parent: e03ba84adb62fbc6049325a5bc00ef6932fa5e39
Author: Eric W. Biederman [EMAIL PROTECTED]
AuthorDate: Sun Dec 2 00:33:17 2007 +1100
Committer: Herbert Xu [EMAIL PROTECTED]
CommitDate: Sun Dec 2 00:33:17 2007 +1100
[NETNS]: Fix /proc/net breakage
Well I clearly goofed when I added the initial network namespace
support
for /proc/net. Currently things work but there are odd details
visible to
user space, even when we have a single network namespace.
Since we do not cache proc_dir_entry dentries at the moment we can just
modify -lookup to return a different directory inode depending on the
network namespace of the process looking at /proc/net, replacing the
current technique of using a magic and fragile follow_link method.
To accomplish that this patch:
- introduces a shadow_proc method to allow different dentries to
be returned from proc_lookup.
- Removes the old /proc/net follow_link magic
- Fixes a weakness in our not caching of proc generic dentries.
As shadow_proc uses a task struct to decided which dentry to return we
can
go back later and fix the proc generic caching without modifying any
code
that uses the shadow_proc method.
This patch caused the binfmt_misc regression reported in
http://bugzilla.kernel.org/show_bug.cgi?id=9504
This patch also doesn't allow to mount /proc/bus/usb
Does Denis's patch fix it?
Yes, this patch solve the problem.
Tested-by: Giacomo Catenazzi [EMAIL PROTECTED]
ciao
cate
Thanks.
From: Denis V. Lunev [EMAIL PROTECTED]
/proc/sys/fs/binfmt_misc dentry disappeared during d_revalidate.
d_revalidate only dentries from shadowed one and below.
http://bugzilla.kernel.org/show_bug.cgi?id=9504
Cc: Eric W. Biederman [EMAIL PROTECTED]
Cc: Marcus Better [EMAIL PROTECTED]
Signed-off-by: Denis V. Lunev [EMAIL PROTECTED]
Cc: Marcus Better [EMAIL PROTECTED]
Signed-off-by: Andrew Morton [EMAIL PROTECTED]
---
fs/proc/generic.c | 14 --
1 file changed, 12 insertions(+), 2 deletions(-)
diff -puN fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
fs/proc/generic.c
--- a/fs/proc/generic.c~lost-content-of-proc-sys-fs-binfmt_misc
+++ a/fs/proc/generic.c
@@ -380,12 +380,17 @@ static int proc_revalidate_dentry(struct
return 0;
}
-static struct dentry_operations proc_dentry_operations =
+static struct dentry_operations proc_dentry_shadow_operations =
{
.d_delete = proc_delete_dentry,
.d_revalidate = proc_revalidate_dentry,
};
+static struct dentry_operations proc_dentry_operations =
+{
+ .d_delete = proc_delete_dentry,
+};
+
/*
* Don't create negative dentries here, return -ENOENT by hand
* instead.
@@ -394,6 +399,7 @@ struct dentry *proc_lookup(struct inode
{
struct inode *inode = NULL;
struct proc_dir_entry * de;
+ int use_shadow = 0;
int error = -ENOENT;
lock_kernel();
@@ -406,8 +412,10 @@ struct dentry *proc_lookup(struct inode
if (!memcmp(dentry-d_name.name, de-name,
de-namelen)) {
unsigned int ino;
- if (de-shadow_proc)
+ if (de-shadow_proc) {
de = de-shadow_proc(current, de);
+ use_shadow = 1;
+ }
ino = de-low_ino;
de_get(de);
spin_unlock(proc_subdir_lock);
@@ -423,6 +431,8 @@ struct dentry *proc_lookup(struct inode
if (inode) {
dentry-d_op = proc_dentry_operations;
+ dentry-d_op = use_shadow ?
+ proc_dentry_shadow_operations : dentry-d_parent-d_op;
d_add(dentry, inode);
return NULL;
}
_
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