The patch titled Subject: prctl: move PR_GET_AUXV out of PR_MCE_KILL has been added to the -mm mm-hotfixes-unstable branch. Its filename is prctl-move-pr_get_auxv-out-of-pr_mce_kill.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days

------------------------------------------------------ From: Miguel Ojeda ojeda@kernel.org Subject: prctl: move PR_GET_AUXV out of PR_MCE_KILL Date: Sun, 9 Jul 2023 01:33:44 +0200

Somehow PR_GET_AUXV got added into PR_MCE_KILL's switch when the patch was applied [1].

Thus move it out of the switch, to the place the patch added it.

In the recently released v6.4 kernel some user could, in principle, be already using this feature by mapping the right page and passing the PR_GET_AUXV constant as a pointer:

prctl(PR_MCE_KILL, PR_GET_AUXV, ...)

So this does change the behavior for users. We could keep the bug since the other subcases in PR_MCE_KILL (PR_MCE_KILL_CLEAR and PR_MCE_KILL_SET) do not overlap.

However, v6.4 may be recent enough (2 weeks old) that moving the lines (rather than just adding a new case) does not break anybody? Moreover, the documentation in man-pages was just committed today [2].

Link: https://lkml.kernel.org/r/20230708233344.361854-1-ojeda@kernel.org Fixes: ddc65971bb67 ("prctl: add PR_GET_AUXV to copy auxv to userspace") Link: https://lore.kernel.org/all/d81864a7f7f43bca6afa2a09fc2e850e4050ab42.1680611... [1] Link: https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit/?id=8cf0c... [2] Signed-off-by: Miguel Ojeda ojeda@kernel.org Cc: Josh Triplett josh@joshtriplett.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

kernel/sys.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/kernel/sys.c~prctl-move-pr_get_auxv-out-of-pr_mce_kill +++ a/kernel/sys.c @@ -2535,11 +2535,6 @@ SYSCALL_DEFINE5(prctl, int, option, unsi else return -EINVAL; break; - case PR_GET_AUXV: - if (arg4 || arg5) - return -EINVAL; - error = prctl_get_auxv((void __user *)arg2, arg3); - break; default: return -EINVAL; } @@ -2694,6 +2689,11 @@ SYSCALL_DEFINE5(prctl, int, option, unsi case PR_SET_VMA: error = prctl_set_vma(arg2, arg3, arg4, arg5); break; + case PR_GET_AUXV: + if (arg4 || arg5) + return -EINVAL; + error = prctl_get_auxv((void __user *)arg2, arg3); + break; #ifdef CONFIG_KSM case PR_SET_MEMORY_MERGE: if (arg3 || arg4 || arg5) _

Patches currently in -mm which might be from ojeda@kernel.org are

prctl-move-pr_get_auxv-out-of-pr_mce_kill.patch