Messages in this thread | | | Date | Tue, 10 Jan 2012 14:40:27 +0800 | Subject | Re: [PATCH] score: fix off-by-one index into syscall table | From | Eugene Teo <> |
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Cc'ed arnd@arndb.de
ping
On Fri, Jan 6, 2012 at 9:21 PM, Dan Rosenberg <drosenberg@vsecurity.com> wrote: > If the provided system call number is equal to __NR_syscalls, the > current check will pass and a function pointer just after the system > call table may be called, since sys_call_table is an array with total > size __NR_syscalls. Whether or not this is a security bug depends on > what the compiler puts immediately after the system call table. It's > likely that this won't do anything bad because there is an additional > NULL check on the syscall entry, but if there happens to be a non-NULL > value immediately after the system call table, this may result in local > privilege escalation. > > Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> > Cc: stable@kernel.org > Cc: security@kernel.org > --- > arch/score/kernel/entry.S | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/score/kernel/entry.S b/arch/score/kernel/entry.S > index 577abba..83bb960 100644 > --- a/arch/score/kernel/entry.S > +++ b/arch/score/kernel/entry.S > @@ -408,7 +408,7 @@ ENTRY(handle_sys) > sw r9, [r0, PT_EPC] > > cmpi.c r27, __NR_syscalls # check syscall number > - bgtu illegal_syscall > + bgeu illegal_syscall > > slli r8, r27, 2 # get syscall routine > la r11, sys_call_table > > -- 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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