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| author | Kees Cook <keescook@chromium.org> | 2016-02-17 14:41:13 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-02-22 08:51:37 +0100 |
| commit | d2aa1acad22f1bdd0cfa67b3861800e392254454 (patch) | |
| tree | 1f3b88086e364e87714dfcaeb66add3bbca81800 /kernel/debug | |
| parent | e267d97b83d9cecc16c54825f9f3ac7f72dc1e1e (diff) | |
| download | linux-d2aa1acad22f1bdd0cfa67b3861800e392254454.tar.gz linux-d2aa1acad22f1bdd0cfa67b3861800e392254454.tar.bz2 linux-d2aa1acad22f1bdd0cfa67b3861800e392254454.zip | |
mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
It may be useful to debug writes to the readonly sections of memory,
so provide a cmdline "rodata=off" to allow for this. This can be
expanded in the future to support "log" and "write" modes, but that
will need to be architecture-specific.
This also makes KDB software breakpoints more usable, as read-only
mappings can now be disabled on any kernel.
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/1455748879-21872-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/debug')
| -rw-r--r-- | kernel/debug/kdb/kdb_bp.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/kernel/debug/kdb/kdb_bp.c b/kernel/debug/kdb/kdb_bp.c index e1dbf4a2c69e..90ff129c88a2 100644 --- a/kernel/debug/kdb/kdb_bp.c +++ b/kernel/debug/kdb/kdb_bp.c @@ -153,13 +153,11 @@ static int _kdb_bp_install(struct pt_regs *regs, kdb_bp_t *bp) } else { kdb_printf("%s: failed to set breakpoint at 0x%lx\n", __func__, bp->bp_addr); -#ifdef CONFIG_DEBUG_RODATA if (!bp->bp_type) { kdb_printf("Software breakpoints are unavailable.\n" - " Change the kernel CONFIG_DEBUG_RODATA=n\n" + " Boot the kernel with rodata=off\n" " OR use hw breaks: help bph\n"); } -#endif return 1; } return 0; |