Commit-ID: 7fdfe1e40b225b1d163f9afed2fa3f04442dbaad
Gitweb: https://git.kernel.org/tip/7fdfe1e40b225b1d163f9afed2fa3f04442dbaad
Author: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
AuthorDate: Thu, 25 Apr 2019 17:11:39 -0700
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 30 Apr 2019 12:38:00 +0200
x86/ftrace: Use vmalloc special flag
Use new flag VM_FLUSH_RESET_PERMS for handling freeing of special
permissioned memory in vmalloc and remove places where memory was set NX
and RW before freeing which is no longer needed.
Tested-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Cc: <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: <ard.biesheuvel@xxxxxxxxxx>
Cc: <deneen.t.dock@xxxxxxxxx>
Cc: <kernel-hardening@xxxxxxxxxxxxxxxxxx>
Cc: <kristen@xxxxxxxxxxxxxxx>
Cc: <linux_dti@xxxxxxxxxx>
Cc: <will.deacon@xxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20190426001143.4983-20-namit@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/kernel/ftrace.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 53ba1aa3a01f..0caf8122d680 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -678,12 +678,8 @@ static inline void *alloc_tramp(unsigned long size)
{
return module_alloc(size);
}
-static inline void tramp_free(void *tramp, int size)
+static inline void tramp_free(void *tramp)
{
- int npages = PAGE_ALIGN(size) >> PAGE_SHIFT;
-
- set_memory_nx((unsigned long)tramp, npages);
- set_memory_rw((unsigned long)tramp, npages);
module_memfree(tramp);
}
#else
@@ -692,7 +688,7 @@ static inline void *alloc_tramp(unsigned long size)
{
return NULL;
}
-static inline void tramp_free(void *tramp, int size) { }
+static inline void tramp_free(void *tramp) { }
#endif
/* Defined as markers to the end of the ftrace default trampolines */
@@ -808,6 +804,8 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
/* ALLOC_TRAMP flags lets us know we created it */
ops->flags |= FTRACE_OPS_FL_ALLOC_TRAMP;
+ set_vm_flush_reset_perms(trampoline);
+
/*
* Module allocation needs to be completed by making the page
* executable. The page is still writable, which is a security hazard,
@@ -816,7 +814,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
set_memory_x((unsigned long)trampoline, npages);
return (unsigned long)trampoline;
fail:
- tramp_free(trampoline, *tramp_size);
+ tramp_free(trampoline);
return 0;
}
@@ -947,7 +945,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops)
if (!ops || !(ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP))
return;
- tramp_free((void *)ops->trampoline, ops->trampoline_size);
+ tramp_free((void *)ops->trampoline);
ops->trampoline = 0;
}
|