From d71f290b4e98a39f49f2595a13be3b4d5ce8e1f1 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Tue, 13 May 2014 23:58:24 +0100 Subject: metag: Reduce maximum stack size to 256MB Specify the maximum stack size for arches where the stack grows upward (parisc and metag) in asm/processor.h rather than hard coding in fs/exec.c so that metag can specify a smaller value of 256MB rather than 1GB. This fixes a BUG on metag if the RLIMIT_STACK hard limit is increased beyond a safe value by root. E.g. when starting a process after running "ulimit -H -s unlimited" it will then attempt to use a stack size of the maximum 1GB which is far too big for metag's limited user virtual address space (stack_top is usually 0x3ffff000): BUG: failure at fs/exec.c:589/shift_arg_pages()! Signed-off-by: James Hogan Cc: Helge Deller Cc: "James E.J. Bottomley" Cc: linux-parisc@vger.kernel.org Cc: linux-metag@vger.kernel.org Cc: John David Anglin Cc: stable@vger.kernel.org # only needed for >= v3.9 (arch/metag) --- fs/exec.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/exec.c') diff --git a/fs/exec.c b/fs/exec.c index 476f3ebf437e..238b7aa26f68 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -657,10 +657,10 @@ int setup_arg_pages(struct linux_binprm *bprm, unsigned long rlim_stack; #ifdef CONFIG_STACK_GROWSUP - /* Limit stack size to 1GB */ + /* Limit stack size */ stack_base = rlimit_max(RLIMIT_STACK); - if (stack_base > (1 << 30)) - stack_base = 1 << 30; + if (stack_base > STACK_SIZE_MAX) + stack_base = STACK_SIZE_MAX; /* Make sure we didn't let the argument array grow too large. */ if (vma->vm_end - vma->vm_start > stack_base) -- cgit v1.2.3 From e041e328c4b41e1db79bfe5ba9992c2ed771ad19 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 21 May 2014 17:32:19 +0200 Subject: perf: Fix perf_event_comm() vs. exec() assumption perf_event_comm() assumes that set_task_comm() is only called on exec(), and in particular that its only called on current. Neither are true, as Dave reported a WARN triggered by set_task_comm() being called on !current. Separate the exec() hook from the comm hook. Reported-by: Dave Jones Signed-off-by: Peter Zijlstra Cc: Alexander Viro Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/20140521153219.GH5226@laptop.programming.kicks-ass.net [ Build fix. ] Signed-off-by: Ingo Molnar --- fs/exec.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/exec.c') diff --git a/fs/exec.c b/fs/exec.c index 238b7aa26f68..a038a41a3677 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1110,6 +1110,7 @@ void setup_new_exec(struct linux_binprm * bprm) else set_dumpable(current->mm, suid_dumpable); + perf_event_exec(); set_task_comm(current, kbasename(bprm->filename)); /* Set the new mm task size. We have to do that late because it may -- cgit v1.2.3