* [tip: x86/iopl] x86/ptrace: Prevent truncation of bitmap size
@ 2019-11-16 11:51 tip-bot2 for Thomas Gleixner
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot2 for Thomas Gleixner @ 2019-11-16 11:51 UTC (permalink / raw)
To: linux-tip-commits
Cc: Thomas Gleixner, Ingo Molnar, Andy Lutomirski, Borislav Petkov,
linux-kernel
The following commit has been merged into the x86/iopl branch of tip:
Commit-ID: 8c40397f22a4ff7996d3abdc2d9d1d90f9fc8054
Gitweb: https://git.kernel.org/tip/8c40397f22a4ff7996d3abdc2d9d1d90f9fc8054
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Mon, 11 Nov 2019 23:03:15 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 16 Nov 2019 11:23:59 +01:00
x86/ptrace: Prevent truncation of bitmap size
The active() callback of the IO bitmap regset divides the IO bitmap size by
the word size (32/64 bit). As the I/O bitmap size is in bytes the active
check fails for bitmap sizes of 1-3 bytes on 32bit and 1-7 bytes on 64bit.
Use DIV_ROUND_UP() instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/kernel/ptrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 3c5bbe8..7c52674 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -697,7 +697,7 @@ static int ptrace_set_debugreg(struct task_struct *tsk, int n,
static int ioperm_active(struct task_struct *target,
const struct user_regset *regset)
{
- return target->thread.io_bitmap_max / regset->size;
+ return DIV_ROUND_UP(target->thread.io_bitmap_max, regset->size);
}
static int ioperm_get(struct task_struct *target,
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [tip: x86/iopl] x86/ptrace: Prevent truncation of bitmap size
2019-11-13 20:42 [patch V3 01/20] " Thomas Gleixner
@ 2019-11-15 21:12 ` tip-bot2 for Thomas Gleixner
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot2 for Thomas Gleixner @ 2019-11-15 21:12 UTC (permalink / raw)
To: linux-tip-commits
Cc: Thomas Gleixner, Ingo Molnar, Andy Lutomirski,
Peter Zijlstra (Intel),
Borislav Petkov, linux-kernel
The following commit has been merged into the x86/iopl branch of tip:
Commit-ID: c5d623b17c2424272b3355a524b094ff02cfd9aa
Gitweb: https://git.kernel.org/tip/c5d623b17c2424272b3355a524b094ff02cfd9aa
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Wed, 13 Nov 2019 21:42:41 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 14 Nov 2019 20:14:59 +01:00
x86/ptrace: Prevent truncation of bitmap size
The active() callback of the IO bitmap regset divides the IO bitmap size by
the word size (32/64 bit). As the I/O bitmap size is in bytes the active
check fails for bitmap sizes of 1-3 bytes on 32bit and 1-7 bytes on 64bit.
Use DIV_ROUND_UP() instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191113210103.819769574@linutronix.de
---
arch/x86/kernel/ptrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 3c5bbe8..7c52674 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -697,7 +697,7 @@ static int ptrace_set_debugreg(struct task_struct *tsk, int n,
static int ioperm_active(struct task_struct *target,
const struct user_regset *regset)
{
- return target->thread.io_bitmap_max / regset->size;
+ return DIV_ROUND_UP(target->thread.io_bitmap_max, regset->size);
}
static int ioperm_get(struct task_struct *target,
^ permalink raw reply related [flat|nested] 2+ messages in thread
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2019-11-13 20:42 [patch V3 01/20] " Thomas Gleixner
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