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| author | Peter Zijlstra <peterz@infradead.org> | 2022-03-08 16:30:29 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-03-15 10:32:37 +0100 |
| commit | aebfd12521d9c7d0b502cf6d06314cfbcdccfe3b (patch) | |
| tree | 32b122cd707b1a26aef2d1ac5612f013ee2821e4 /kernel/kprobes.c | |
| parent | 6649fa876da4c505548b8e8945a6fc48e62e427c (diff) | |
| download | linux-stable-aebfd12521d9c7d0b502cf6d06314cfbcdccfe3b.tar.gz linux-stable-aebfd12521d9c7d0b502cf6d06314cfbcdccfe3b.tar.bz2 linux-stable-aebfd12521d9c7d0b502cf6d06314cfbcdccfe3b.zip | |
x86/ibt,ftrace: Search for __fentry__ location
Currently a lot of ftrace code assumes __fentry__ is at sym+0. However
with Intel IBT enabled the first instruction of a function will most
likely be ENDBR.
Change ftrace_location() to not only return the __fentry__ location
when called for the __fentry__ location, but also when called for the
sym+0 location.
Then audit/update all callsites of this function to consistently use
these new semantics.
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154318.227581603@infradead.org
Diffstat (limited to 'kernel/kprobes.c')
| -rw-r--r-- | kernel/kprobes.c | 8 |
1 files changed, 2 insertions, 6 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 94cab8c9ce56..6d1e11cda4f1 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1562,14 +1562,10 @@ static inline int warn_kprobe_rereg(struct kprobe *p) static int check_ftrace_location(struct kprobe *p) { - unsigned long ftrace_addr; + unsigned long addr = (unsigned long)p->addr; - ftrace_addr = ftrace_location((unsigned long)p->addr); - if (ftrace_addr) { + if (ftrace_location(addr) == addr) { #ifdef CONFIG_KPROBES_ON_FTRACE - /* Given address is not on the instruction boundary */ - if ((unsigned long)p->addr != ftrace_addr) - return -EILSEQ; p->flags |= KPROBE_FLAG_FTRACE; #else /* !CONFIG_KPROBES_ON_FTRACE */ return -EINVAL; |