On Tue, Mar 08, 2022 at 01:35:03PM -0600, Eric W. Biederman wrote:
>
> Kees,
>
> Please pull the coredump-vma-snapshot-fix branch from the git tree:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git coredump-vma-snapshot-fix
>
> HEAD: 390031c942116d4733310f0684beb8db19885fe6 coredump: Use the vma snapshot in fill_files_note
>
> Matthew Wilcox has reported that a missing mmap_lock in file_files_note,
> which could cause trouble.
>
> Refactor the code and clean it up so that the vma snapshot makes
> it to fill_files_note, and then use the vma snapshot in fill_files_note.
>
> Eric W. Biederman (5):
> coredump: Move definition of struct coredump_params into coredump.h
> coredump: Snapshot the vmas in do_coredump
> coredump: Remove the WARN_ON in dump_vma_snapshot
> coredump/elf: Pass coredump_params into fill_note_info
> coredump: Use the vma snapshot in fill_files_note
>
> fs/binfmt_elf.c | 66 ++++++++++++++++++++++--------------------------
> fs/binfmt_elf_fdpic.c | 18 +++++--------
> fs/binfmt_flat.c | 1 +
> fs/coredump.c | 59 ++++++++++++++++++++++++++++---------------
> include/linux/binfmts.h | 13 +---------
> include/linux/coredump.h | 20 ++++++++++++---
> 6 files changed, 93 insertions(+), 84 deletions(-)
>
> ---
>
> Kees I realized I needed to rebase this on Jann Horn's commit
> 84158b7f6a06 ("coredump: Also dump first pages of non-executable ELF
> libraries"). Unfortunately before I got that done I got distracted and
> these changes have been sitting in limbo for most of the development
> cycle. Since you are running a tree that is including changes like this
> including Jann's can you please pull these changes into your tree.
Sure! Can you make a signed tag for this pull?
If it helps, my workflow look like this, though I assume there might be
better ways. (tl;dr: "git tag -s TAG BRANCH")
PULL_BRANCH=name-of-branch
BASE=sha-of-base
FOR=someone
TOPIC=topic-name
TAG="for-$FOR/$TOPIC"
SIGNED=~/.pull-request-signed-"$TAG"
echo "$TOPIC update" > "$SIGNED"
git request-pull "$BASE" git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git "$PULL_BRANCH" | awk '{print "# " $0}' >> "$SIGNED"
vi "$SIGNED"
git tag -sF "$SIGNED" "$TAG" "$PULL_BRANCH"
git push origin "$PULL_BRANCH"
git push origin +"$TAG"
--
Kees Cook
Kees Cook <[email protected]> writes:
> On Tue, Mar 08, 2022 at 01:35:03PM -0600, Eric W. Biederman wrote:
>>
>> Kees,
>>
>> Please pull the coredump-vma-snapshot-fix branch from the git tree:
>>
>> git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git coredump-vma-snapshot-fix
>>
>> HEAD: 390031c942116d4733310f0684beb8db19885fe6 coredump: Use the vma snapshot in fill_files_note
>>
>> Matthew Wilcox has reported that a missing mmap_lock in file_files_note,
>> which could cause trouble.
>>
>> Refactor the code and clean it up so that the vma snapshot makes
>> it to fill_files_note, and then use the vma snapshot in fill_files_note.
>>
>> Eric W. Biederman (5):
>> coredump: Move definition of struct coredump_params into coredump.h
>> coredump: Snapshot the vmas in do_coredump
>> coredump: Remove the WARN_ON in dump_vma_snapshot
>> coredump/elf: Pass coredump_params into fill_note_info
>> coredump: Use the vma snapshot in fill_files_note
>>
>> fs/binfmt_elf.c | 66 ++++++++++++++++++++++--------------------------
>> fs/binfmt_elf_fdpic.c | 18 +++++--------
>> fs/binfmt_flat.c | 1 +
>> fs/coredump.c | 59 ++++++++++++++++++++++++++++---------------
>> include/linux/binfmts.h | 13 +---------
>> include/linux/coredump.h | 20 ++++++++++++---
>> 6 files changed, 93 insertions(+), 84 deletions(-)
>>
>> ---
>>
>> Kees I realized I needed to rebase this on Jann Horn's commit
>> 84158b7f6a06 ("coredump: Also dump first pages of non-executable ELF
>> libraries"). Unfortunately before I got that done I got distracted and
>> these changes have been sitting in limbo for most of the development
>> cycle. Since you are running a tree that is including changes like this
>> including Jann's can you please pull these changes into your tree.
>
> Sure! Can you make a signed tag for this pull?
Not yet.
Hopefully I will get the time to set that up soon, but I am not at all
setup to do signed tags at this point.
> If it helps, my workflow look like this, though I assume there might be
> better ways. (tl;dr: "git tag -s TAG BRANCH")
>
>
> PULL_BRANCH=name-of-branch
> BASE=sha-of-base
> FOR=someone
> TOPIC=topic-name
>
> TAG="for-$FOR/$TOPIC"
> SIGNED=~/.pull-request-signed-"$TAG"
> echo "$TOPIC update" > "$SIGNED"
> git request-pull "$BASE" git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git "$PULL_BRANCH" | awk '{print "# " $0}' >> "$SIGNED"
> vi "$SIGNED"
>
> git tag -sF "$SIGNED" "$TAG" "$PULL_BRANCH"
> git push origin "$PULL_BRANCH"
> git push origin +"$TAG"
Thanks. That looks like a good place to start.
Eric
On Wed, Mar 09, 2022 at 10:29:10AM -0600, Eric W. Biederman wrote:
> Kees Cook <[email protected]> writes:
>
> > On Tue, Mar 08, 2022 at 01:35:03PM -0600, Eric W. Biederman wrote:
> >>
> >> Kees,
> >>
> >> Please pull the coredump-vma-snapshot-fix branch from the git tree:
> >>
> >> git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git coredump-vma-snapshot-fix
> >>
> >> HEAD: 390031c942116d4733310f0684beb8db19885fe6 coredump: Use the vma snapshot in fill_files_note
> >>
> >> Matthew Wilcox has reported that a missing mmap_lock in file_files_note,
> >> which could cause trouble.
> >>
> >> Refactor the code and clean it up so that the vma snapshot makes
> >> it to fill_files_note, and then use the vma snapshot in fill_files_note.
> >>
> >> Eric W. Biederman (5):
> >> coredump: Move definition of struct coredump_params into coredump.h
> >> coredump: Snapshot the vmas in do_coredump
> >> coredump: Remove the WARN_ON in dump_vma_snapshot
> >> coredump/elf: Pass coredump_params into fill_note_info
> >> coredump: Use the vma snapshot in fill_files_note
> >>
> >> fs/binfmt_elf.c | 66 ++++++++++++++++++++++--------------------------
> >> fs/binfmt_elf_fdpic.c | 18 +++++--------
> >> fs/binfmt_flat.c | 1 +
> >> fs/coredump.c | 59 ++++++++++++++++++++++++++++---------------
> >> include/linux/binfmts.h | 13 +---------
> >> include/linux/coredump.h | 20 ++++++++++++---
> >> 6 files changed, 93 insertions(+), 84 deletions(-)
> >>
> >> ---
> >>
> >> Kees I realized I needed to rebase this on Jann Horn's commit
> >> 84158b7f6a06 ("coredump: Also dump first pages of non-executable ELF
> >> libraries"). Unfortunately before I got that done I got distracted and
> >> these changes have been sitting in limbo for most of the development
> >> cycle. Since you are running a tree that is including changes like this
> >> including Jann's can you please pull these changes into your tree.
> >
> > Sure! Can you make a signed tag for this pull?
>
> Not yet.
>
> Hopefully I will get the time to set that up soon, but I am not at all
> setup to do signed tags at this point.
Okay, cool. Since I'd already review these before, I've pulled and it
should be in -next now.
> [...]
> Thanks. That looks like a good place to start.
I will try to clean up that work-flow and stuff it into my kernel-tools
repo.
--
Kees Cook
Kees Cook <[email protected]> writes:
> On Wed, Mar 09, 2022 at 10:29:10AM -0600, Eric W. Biederman wrote:
>> Kees Cook <[email protected]> writes:
>>
>> > On Tue, Mar 08, 2022 at 01:35:03PM -0600, Eric W. Biederman wrote:
>> >>
>> >> Kees,
>> >>
>> >> Please pull the coredump-vma-snapshot-fix branch from the git tree:
>> >>
>> >> git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git coredump-vma-snapshot-fix
>> >>
>> >> HEAD: 390031c942116d4733310f0684beb8db19885fe6 coredump: Use the vma snapshot in fill_files_note
>> >>
>> >> Matthew Wilcox has reported that a missing mmap_lock in file_files_note,
>> >> which could cause trouble.
>> >>
>> >> Refactor the code and clean it up so that the vma snapshot makes
>> >> it to fill_files_note, and then use the vma snapshot in fill_files_note.
>> >>
>> >> Eric W. Biederman (5):
>> >> coredump: Move definition of struct coredump_params into coredump.h
>> >> coredump: Snapshot the vmas in do_coredump
>> >> coredump: Remove the WARN_ON in dump_vma_snapshot
>> >> coredump/elf: Pass coredump_params into fill_note_info
>> >> coredump: Use the vma snapshot in fill_files_note
>> >>
>> >> fs/binfmt_elf.c | 66 ++++++++++++++++++++++--------------------------
>> >> fs/binfmt_elf_fdpic.c | 18 +++++--------
>> >> fs/binfmt_flat.c | 1 +
>> >> fs/coredump.c | 59 ++++++++++++++++++++++++++++---------------
>> >> include/linux/binfmts.h | 13 +---------
>> >> include/linux/coredump.h | 20 ++++++++++++---
>> >> 6 files changed, 93 insertions(+), 84 deletions(-)
>> >>
>> >> ---
>> >>
>> >> Kees I realized I needed to rebase this on Jann Horn's commit
>> >> 84158b7f6a06 ("coredump: Also dump first pages of non-executable ELF
>> >> libraries"). Unfortunately before I got that done I got distracted and
>> >> these changes have been sitting in limbo for most of the development
>> >> cycle. Since you are running a tree that is including changes like this
>> >> including Jann's can you please pull these changes into your tree.
>> >
>> > Sure! Can you make a signed tag for this pull?
>>
>> Not yet.
>>
>> Hopefully I will get the time to set that up soon, but I am not at all
>> setup to do signed tags at this point.
>
> Okay, cool. Since I'd already review these before, I've pulled and it
> should be in -next now.
>
>> [...]
>> Thanks. That looks like a good place to start.
>
> I will try to clean up that work-flow and stuff it into my kernel-tools
> repo.
It turns out I missed a crazy corner case of binfmt_flat, when coredumps
are disabled. This fixes a compile error that was reported.
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git coredump-vma-snapshot-fix-for-v5.18
HEAD: f833116ad2c3eabf9c739946170e07825cca67ed coredump: Don't compile flat_core_dump when coredumps are disabled
Can you include this as well.
Thank you,
Eric
This is the entire patch.
From: "Eric W. Biederman" <[email protected]>
Date: Wed, 9 Mar 2022 10:37:07 -0600
Subject: [PATCH] coredump: Don't compile flat_core_dump when coredumps are disabled
Recently the kernel test robot reported:
> In file included from include/linux/kernel.h:29,
> from fs/binfmt_flat.c:21:
> fs/binfmt_flat.c: In function 'flat_core_dump':
> >> fs/binfmt_flat.c:121:50: error: invalid use of undefined type 'struct coredump_params'
> 121 | current->comm, current->pid, cprm->siginfo->si_signo);
> | ^~
> include/linux/printk.h:418:33: note: in definition of macro 'printk_index_wrap'
> 418 | _p_func(_fmt, ##__VA_ARGS__); \
> | ^~~~~~~~~~~
> include/linux/printk.h:499:9: note: in expansion of macro 'printk'
> 499 | printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
> | ^~~~~~
> fs/binfmt_flat.c:120:9: note: in expansion of macro 'pr_warn'
> 120 | pr_warn("Process %s:%d received signr %d and should have core dumped\n",
> | ^~~~~~~
> At top level:
> fs/binfmt_flat.c:118:12: warning: 'flat_core_dump' defined but not used [-Wunused-function]
> 118 | static int flat_core_dump(struct coredump_params *cprm)
> | ^~~~~~~~~~~~~~
The little dinky do nothing function flat_core_dump has always been
compiled unconditionally. With my change to move coredump_params into
coredump.h coredump_params reasonably becomes unavailable when
coredump support is not compiled in. Fix this old issue by simply not
compiling flat_core_dump when coredump support is not supported.
Fixes: a99a3e2efaf1 ("coredump: Move definition of struct coredump_params into coredump.h")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: "Eric W. Biederman" <[email protected]>
---
fs/binfmt_flat.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 208cdce16de1..626898150011 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -98,7 +98,9 @@ static int load_flat_shared_library(int id, struct lib_info *p);
#endif
static int load_flat_binary(struct linux_binprm *);
+#ifdef CONFIG_COREDUMP
static int flat_core_dump(struct coredump_params *cprm);
+#endif
static struct linux_binfmt flat_format = {
.module = THIS_MODULE,
@@ -115,12 +117,14 @@ static struct linux_binfmt flat_format = {
* Currently only a stub-function.
*/
+#ifdef CONFIG_COREDUMP
static int flat_core_dump(struct coredump_params *cprm)
{
pr_warn("Process %s:%d received signr %d and should have core dumped\n",
current->comm, current->pid, cprm->siginfo->si_signo);
return 1;
}
+#endif
/****************************************************************************/
/*
--
2.29.2
On Wed, Mar 09, 2022 at 02:27:07PM -0600, Eric W. Biederman wrote:
> It turns out I missed a crazy corner case of binfmt_flat, when coredumps
> are disabled. This fixes a compile error that was reported.
>
> git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git coredump-vma-snapshot-fix-for-v5.18
> HEAD: f833116ad2c3eabf9c739946170e07825cca67ed coredump: Don't compile flat_core_dump when coredumps are disabled
>
> Can you include this as well.
Thanks! Pulled and pushed out.
--
Kees Cook