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author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-04-11 05:48:05 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-04-11 05:48:05 +0300 |
commit | e8c39d0f57f358950356a8e44ee5159f57f86ec5 (patch) | |
tree | 05e9af52843ce3f26e45c2db94a8e29f5a629182 | |
parent | 03a55b63919f4b52b9c323d9a43ccccdc1cdb33b (diff) | |
parent | 325f3fb551f8cd672dbbfc4cf58b14f9ee3fc9e8 (diff) | |
download | linux-e8c39d0f57f358950356a8e44ee5159f57f86ec5.tar.xz |
Merge tag 'probes-fixes-v6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fixes from Masami Hiramatsu:
"Fix possible use-after-free issue on kprobe registration.
check_kprobe_address_safe() uses `is_module_text_address()` and
`__module_text_address()` separately.
As a result, if the probed address is in a module that is being
unloaded, the first `is_module_text_address()` might return true but
then the `__module_text_address()` call might return NULL if the
module has been unloaded between the two.
The result is that kprobe believes the probe is on the kernel text,
and skips getting a module reference. In this case, when it arms a
breakpoint on the probe address, it may cause a use-after-free.
To fix this issue, only use `__module_text_address()` once and get a
reference to the module then. If it fails, reject the probe"
* tag 'probes-fixes-v6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
kprobes: Fix possible use-after-free issue on kprobe registration
-rw-r--r-- | kernel/kprobes.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 9d9095e81792..65adc815fc6e 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1567,10 +1567,17 @@ static int check_kprobe_address_safe(struct kprobe *p, jump_label_lock(); preempt_disable(); - /* Ensure it is not in reserved area nor out of text */ - if (!(core_kernel_text((unsigned long) p->addr) || - is_module_text_address((unsigned long) p->addr)) || - in_gate_area_no_mm((unsigned long) p->addr) || + /* Ensure the address is in a text area, and find a module if exists. */ + *probed_mod = NULL; + if (!core_kernel_text((unsigned long) p->addr)) { + *probed_mod = __module_text_address((unsigned long) p->addr); + if (!(*probed_mod)) { + ret = -EINVAL; + goto out; + } + } + /* Ensure it is not in reserved area. */ + if (in_gate_area_no_mm((unsigned long) p->addr) || within_kprobe_blacklist((unsigned long) p->addr) || jump_label_text_reserved(p->addr, p->addr) || static_call_text_reserved(p->addr, p->addr) || @@ -1580,8 +1587,7 @@ static int check_kprobe_address_safe(struct kprobe *p, goto out; } - /* Check if 'p' is probing a module. */ - *probed_mod = __module_text_address((unsigned long) p->addr); + /* Get module refcount and reject __init functions for loaded modules. */ if (*probed_mod) { /* * We must hold a refcount of the probed module while updating |