6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Helge Deller <deller@xxxxxx> [ Upstream commit 793838138c157d4c49f4fb744b170747e3dabf58 ] systemd-254 tries to use prctl(PR_SET_MDWE) for it's MemoryDenyWriteExecute functionality, but fails on parisc which still needs executable stacks in certain combinations of gcc/glibc/kernel. Disable prctl(PR_SET_MDWE) by returning -EINVAL for now on parisc, until userspace has catched up. Signed-off-by: Helge Deller <deller@xxxxxx> Co-developed-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Reported-by: Sam James <sam@xxxxxxxxxx> Closes: https://github.com/systemd/systemd/issues/29775 Tested-by: Sam James <sam@xxxxxxxxxx> Link: https://lore.kernel.org/all/875y2jro9a.fsf@xxxxxxxxxx/ Cc: <stable@xxxxxxxxxxxxxxx> # v6.3+ Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/sys.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/sys.c b/kernel/sys.c index 4a8073c1b2558..7a4ae6d5aecd5 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -2395,6 +2395,10 @@ static inline int prctl_set_mdwe(unsigned long bits, unsigned long arg3, if (bits & PR_MDWE_NO_INHERIT && !(bits & PR_MDWE_REFUSE_EXEC_GAIN)) return -EINVAL; + /* PARISC cannot allow mdwe as it needs writable stacks */ + if (IS_ENABLED(CONFIG_PARISC)) + return -EINVAL; + current_bits = get_current_mdwe(); if (current_bits && current_bits != bits) return -EPERM; /* Cannot unset the flags */ -- 2.42.0
