Mathieu, On 06/15/16 08:01, Mathieu Malaterre wrote: > On my PowerMac device-tree would generate a duplicate name: > > [ 0.023043] device-tree: Duplicate name in PowerPC,G4@0, renamed to "l2-cache#1" > > in this case a newly allocated name is generated by `safe_name`. However > in this case it is never deallocated. > > The bug was found using kmemleak reported as: > > unreferenced object 0xdf532e60 (size 32): > comm "swapper", pid 1, jiffies 4294892300 (age 1993.532s) > hex dump (first 32 bytes): > 6c 32 2d 63 61 63 68 65 23 31 00 dd e4 dd 1e c2 l2-cache#1...... > ec d4 ba ce 04 ec cc de 8e 85 e9 ca c4 ec cc 9e ................ > backtrace: > [<c02d3350>] kvasprintf+0x64/0xc8 > [<c02d3400>] kasprintf+0x4c/0x5c > [<c0453814>] safe_name.isra.1+0x80/0xc4 > [<c04545d8>] __of_attach_node_sysfs+0x6c/0x11c > [<c075f21c>] of_core_init+0x8c/0xf8 > [<c0729594>] kernel_init_freeable+0xd4/0x208 > [<c00047e8>] kernel_init+0x24/0x11c > [<c00158ec>] ret_from_kernel_thread+0x5c/0x64 > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=120331 > Signed-off-by: Mathieu Malaterre <mathieu.malaterre@xxxxxxxxx> > --- > drivers/of/base.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index ebf84e3..3cb11df 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -174,11 +174,15 @@ int __of_attach_node_sysfs(struct device_node *np) > rc = kobject_add(&np->kobj, NULL, "%s", > safe_name(&of_kset->kobj, "base")); > } else { > - name = safe_name(&np->parent->kobj, kbasename(np->full_name)); > + const char *orig_name = kbasename(np->full_name); > + > + name = safe_name(&np->parent->kobj, orig_name); > if (!name || !name[0]) > return -EINVAL; > > rc = kobject_add(&np->kobj, &np->parent->kobj, "%s", name); > + if (name != orig_name) > + kfree(name); > } > if (rc) > return rc; > Thanks for reporting the issue and the cause of the issue. You have exposed an issue that affects additional safe_name() call sites that the proposed patch does not fix. I will send you another patch that also addresses the other safe_name() call sites, please test it to see if it fixes the memory leak that you reported. -Frank -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
