Messages in this thread | | | Date | Wed, 15 Nov 2006 11:06:34 -0600 | From | "Bill O'Donnell" <> | Subject | Re: [PATCH 1/1] security: introduce fs caps |
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On Wed, Nov 15, 2006 at 09:08:55PM +0900, KaiGai Kohei wrote: | Serge E. Hallyn wrote: | >Quoting Bill O'Donnell (billodo@sgi.com): | >>8102 execve("/sbin/setfcaps", ["setfcaps", "cap_net_raw=ep", | >>"/bin/ping"], [/* 67 vars */]) = 0 | - snip - | >>8102 capget(0x19980330, 0, {0, 0, 0}) = -1 EINVAL (Invalid argument) | > | >I don't see why this capget is returning -EINVAL. In fact I don't see | >why it happens at all - cap_inode_setxattr would check | >capable(CAP_SYS_ADMIN), but setxattr hasn't been called yet. Looking at | >both libcap and setfcaps.c, I don't see where the capget comes from. | > | >As for the -EINVAL, kernel/capability.c:sys_capget() returns -EINVAL if | >the _LINUX_CAPABILITY_VERSION is wrong - you have 0x19980330 which is | >correct - if pid < 0 - but you send in 0 - or if security_capget | >returns -EINVAL, which cap_capget (and dummy_capget) don't do. | > | >Kaigai, do you have any ideas? | | Bill said that he uses SLES10/ia64, so the version of libcap is different | from Fedora Core's one. 'libcap-1.92-499.4.src.rpm' is bandled. | | Then, I found a strange code in libcap-1.92-499.4.src.rpm. | | The setfcaps calls cap_from_text() which is defined in libcap to parse | the command line argument. It has the following function call chains: | | cap_from_text() | -> cap_init() | -> _libcap_establish_api()
- snip -
| capget() is called from _libcap_establish_api() with full-zeroed | __user_cap_header_struct object at first time. | The result of this, sys_capget() in kernel will return -EINVAL. | (Why did strace say the first argument is 0x19980330?) | | Probably, Bill didn't update libcap.so. No, I didn't... certify:~/libcap-1.10/progs # ls -altr /lib/libcap* -rwxr-xr-x 1 root root 22672 2006-06-16 09:56 /lib/libcap.so.1.92 -rw-r--r-- 1 root root 53363 2006-11-13 16:04 /lib/libcap.so.1.10 lrwxrwxrwx 1 root root 14 2006-11-13 16:04 /lib/libcap.so.1 ->libcap.so.1.92 lrwxrwxrwx 1 root root 11 2006-11-13 16:04 /lib/libcap.so -> libcap.so.1
| | But I can't recommend Bill to update libcap immediately. | As Hawk Xu said, it may cause a serious problem on the distro | except Fedora Core 6. :(
What version of libcap is on FC6?
| | I have to recommend to use 'fscaps-1.0-kg.i386.rpm' now. | It includes the implementation of interaction between application and xattr. | (Of couse, it's one of the features which should be provided by libcap.)
But that won't work on ia64 will it?
Thanks, Bill
-- Bill O'Donnell SGI 651.683.3079 billodo@sgi.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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