From: Mark Brown broonie@kernel.org
[ Upstream commit 7ddcaf78e93c9282b4d92184f511b4d5bee75355 ]
The signal code has a limit of 64K on the size of a stack frame that it will generate, if this limit is exceeded then a process will be killed if it receives a signal. Unfortunately with the advent of SME this limit is too small - the maximum possible size of the ZA register alone is 64K. This is not an issue for practical systems at present but is easily seen using virtual platforms.
Raise the limit to 256K, this is substantially more than could be used by any current architecture extension.
Signed-off-by: Mark Brown broonie@kernel.org Acked-by: Catalin Marinas catalin.marinas@arm.com Link: https://lore.kernel.org/r/20220817182324.638214-2-broonie@kernel.org Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index f6d3278c1a4e0..92afd44db9dd8 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -91,7 +91,7 @@ static size_t sigframe_size(struct rt_sigframe_user_layout const *user) * not taken into account. This limit is not a guarantee and is * NOT ABI. */ -#define SIGFRAME_MAXSZ SZ_64K +#define SIGFRAME_MAXSZ SZ_256K
static int __sigframe_alloc(struct rt_sigframe_user_layout *user, unsigned long *offset, size_t size, bool extend)