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| author |   Petr Mladek <pmladek@suse.com> | 2020-01-16 16:31:45 +0100 |
|---|---|---|
| committer |   Jiri Kosina <jkosina@suse.cz> | 2020-01-17 11:12:06 +0100 |
| commit | f46e49a9cc3814f3564477f0fffc00e0a2bc9e80 (patch) | |
| tree | 4b9fbbe6954225043b3b2f4261ae861b16119d55 | |
| parent | livepatch/samples/selftest: Use klp_shadow_alloc() API correctly (diff) | |
| download | wireguard-linux-f46e49a9cc3814f3564477f0fffc00e0a2bc9e80.tar.xz wireguard-linux-f46e49a9cc3814f3564477f0fffc00e0a2bc9e80.zip | |
livepatch: Handle allocation failure in the sample of shadow variable API
klp_shadow_alloc() is not handled in the sample of shadow variable API.
It is not strictly necessary because livepatch_fix1_dummy_free() is
able to handle the potential failure. But it is an example and it should
use the API a clean way.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| -rw-r--r-- | samples/livepatch/livepatch-shadow-fix1.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c index de0363b288a7..918ce17b43fd 100644 --- a/samples/livepatch/livepatch-shadow-fix1.c +++ b/samples/livepatch/livepatch-shadow-fix1.c @@ -66,6 +66,7 @@ static struct dummy *livepatch_fix1_dummy_alloc(void) { struct dummy *d; int *leak; + int **shadow_leak; d = kzalloc(sizeof(*d), GFP_KERNEL); if (!d) @@ -80,18 +81,27 @@ static struct dummy *livepatch_fix1_dummy_alloc(void) * pointer to handle resource release. */ leak = kzalloc(sizeof(*leak), GFP_KERNEL); - if (!leak) { - kfree(d); - return NULL; + if (!leak) + goto err_leak; + + shadow_leak = klp_shadow_alloc(d, SV_LEAK, sizeof(leak), GFP_KERNEL, + shadow_leak_ctor, &leak); + if (!shadow_leak) { + pr_err("%s: failed to allocate shadow variable for the leaking pointer: dummy @ %p, leak @ %p\n", + __func__, d, leak); + goto err_shadow; } - klp_shadow_alloc(d, SV_LEAK, sizeof(leak), GFP_KERNEL, - shadow_leak_ctor, &leak); - pr_info("%s: dummy @ %p, expires @ %lx\n", __func__, d, d->jiffies_expire); return d; + +err_shadow: + kfree(leak); +err_leak: + kfree(d); + return NULL; } static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data) |