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| author | Nathan Fontenot <nfont@linux.vnet.ibm.com> | 2015-10-27 18:46:47 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2015-10-28 06:08:18 +0300 |
| commit | f755ecfb8cec7b19dff84295309f2afb24a5afd1 (patch) | |
| tree | 0786fec1e825368514b8db02c53ab31acb66505b /arch/powerpc | |
| parent | 353169acf1858bb2dc3f91475dafabce547de14c (diff) | |
| download | linux-f755ecfb8cec7b19dff84295309f2afb24a5afd1.tar.xz | |
powerpc/pseries: Correct string length in pseries_of_derive_parent()
Commit a030e1e4bbd085bbcfd0a23f8d355fcd41f39bed make a change to use
kstrndup() instead of kmalloc() + strlcpy() in the pseries_of_derive_parent()
routine that introduces a subtle change in the parent path name generated.
The kstrndup() routine will copy n characters followed by a terminating null,
whereas strlcpy() will copy n-1 characters and add a terminating null.
This slight difference results in having a parent path that includes the
tailing '/' character, "/cpus/" vs. "/cpus". This then causes the subsequent
call to of_find_node_by_path() to fail, and in the case of DLPAR add
operations the DLPAR request fails.
This patch decrements the pointer returned from kbasename() to point to the
'/' character before the base name instead of the base name. This then
adjusts the string length calculations to not include the trailing '/'
in the parent path name.
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/platforms/pseries/of_helpers.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/powerpc/platforms/pseries/of_helpers.c b/arch/powerpc/platforms/pseries/of_helpers.c index 4417afef74d4..2798933c0e38 100644 --- a/arch/powerpc/platforms/pseries/of_helpers.c +++ b/arch/powerpc/platforms/pseries/of_helpers.c @@ -17,13 +17,16 @@ struct device_node *pseries_of_derive_parent(const char *path) { struct device_node *parent; char *parent_path = "/"; - const char *tail = kbasename(path); + const char *tail; + + /* We do not want the trailing '/' character */ + tail = kbasename(path) - 1; /* reject if path is "/" */ if (!strcmp(path, "/")) return ERR_PTR(-EINVAL); - if (tail > path + 1) { + if (tail > path) { parent_path = kstrndup(path, tail - path, GFP_KERNEL); if (!parent_path) return ERR_PTR(-ENOMEM); |