Messages in this thread Patch in this message |  | | Date | Fri, 02 Feb 2007 18:35:48 -0800 | From | Chris Wright <> | Subject | [patch 44/59] uml: fix signal frame alignment |
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-stable review patch. If anyone has any objections, please let us know. ------------------
From: Jeff Dike <jdike@addtoit.com>
Use the same signal frame alignment calculations as the underlying architecture. x86_64 appeared to do this, but the "- 8" was really subtracting 8 * sizeof(struct rt_sigframe) rather than 8 bytes.
UML/i386 might have been OK, but I changed the calculation to match i386 just to be sure.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: <stable@kernel.org> Cc: Adrian Bunk <bunk@stusta.de> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Antoine Martin <antoine@nagafix.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org> --- arch/um/sys-i386/signal.c | 3 ++- arch/um/sys-x86_64/signal.c | 5 +++-- 2 files changed, 5 insertions(+), 3 deletions(-)
--- linux-2.6.19.2.orig/arch/um/sys-i386/signal.c +++ linux-2.6.19.2/arch/um/sys-i386/signal.c @@ -219,7 +219,8 @@ int setup_signal_stack_sc(unsigned long unsigned long save_sp = PT_REGS_SP(regs); int err = 0; - stack_top &= -8UL; + /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */ + stack_top = ((stack_top + 4) & -16UL) - 4; frame = (struct sigframe __user *) stack_top - 1; if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) return 1; --- linux-2.6.19.2.orig/arch/um/sys-x86_64/signal.c +++ linux-2.6.19.2/arch/um/sys-x86_64/signal.c @@ -191,8 +191,9 @@ int setup_signal_stack_si(unsigned long struct task_struct *me = current; frame = (struct rt_sigframe __user *) - round_down(stack_top - sizeof(struct rt_sigframe), 16) - 8; - frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128); + round_down(stack_top - sizeof(struct rt_sigframe), 16); + /* Subtract 128 for a red zone and 8 for proper alignment */ + frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8); if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate))) goto out; -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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