Commit 779302e6 authored by Sasha Levin's avatar Sasha Levin Committed by Linus Torvalds

fs/xattr.c:getxattr(): improve handling of allocation failures

This allocation can be as large as 64k.

 - Add __GFP_NOWARN so the falied kmalloc() is silent

 - Fall back to vmalloc() if the kmalloc() failed
Signed-off-by: default avatarSasha Levin <levinsasha928@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 32b4560b
...@@ -427,6 +427,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value, ...@@ -427,6 +427,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
{ {
ssize_t error; ssize_t error;
void *kvalue = NULL; void *kvalue = NULL;
void *vvalue = NULL;
char kname[XATTR_NAME_MAX + 1]; char kname[XATTR_NAME_MAX + 1];
error = strncpy_from_user(kname, name, sizeof(kname)); error = strncpy_from_user(kname, name, sizeof(kname));
...@@ -438,9 +439,13 @@ getxattr(struct dentry *d, const char __user *name, void __user *value, ...@@ -438,9 +439,13 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
if (size) { if (size) {
if (size > XATTR_SIZE_MAX) if (size > XATTR_SIZE_MAX)
size = XATTR_SIZE_MAX; size = XATTR_SIZE_MAX;
kvalue = kzalloc(size, GFP_KERNEL); kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
if (!kvalue) if (!kvalue) {
return -ENOMEM; vvalue = vmalloc(size);
if (!vvalue)
return -ENOMEM;
kvalue = vvalue;
}
} }
error = vfs_getxattr(d, kname, kvalue, size); error = vfs_getxattr(d, kname, kvalue, size);
...@@ -452,7 +457,10 @@ getxattr(struct dentry *d, const char __user *name, void __user *value, ...@@ -452,7 +457,10 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
than XATTR_SIZE_MAX bytes. Not possible. */ than XATTR_SIZE_MAX bytes. Not possible. */
error = -E2BIG; error = -E2BIG;
} }
kfree(kvalue); if (vvalue)
vfree(vvalue);
else
kfree(kvalue);
return error; return error;
} }
......
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