-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Andrew, Serge
The attached patch (e3d27bcb07485a6c8927c8e4f5483d35a99680c3) adds 64-bit capability support to the kernel. This version of the patch is designed to apply against the 2.6.23-mm1 tree. FWIW libcap-2.00 supports this change (and earlier capability formats) http://www.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/ Cheers Andrew Note: to apply this patch against Linus' upstream kernel, you will first have to undo this other patch from Serge: From b68680e4731abbd78863063aaa0dca2a6d8cc723 Mon Sep 17 00:00:00 2001 From: Serge E. Hallyn <[EMAIL PROTECTED]> Date: Sun, 21 Oct 2007 16:41:38 -0700 Subject: [PATCH] capabilities: clean up file capability reading It seems that this patch has made it into 2.6.24-rc1, but it is not present in 2.6.23-mm1. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.6 (GNU/Linux) iD8DBQFHMr5rQheEq9QabfIRAkWuAJ9vQBefhA31KWobFGkIugMnPiS7TwCgkeNg DXC3U5OPNO/w9ERJBltxMKo= =SjLL -----END PGP SIGNATURE-----
>From e3d27bcb07485a6c8927c8e4f5483d35a99680c3 Mon Sep 17 00:00:00 2001 From: Andrew G. Morgan <[EMAIL PROTECTED]> Date: Wed, 7 Nov 2007 23:17:06 -0800 Subject: [PATCH] Add 64-bit capability support to the kernel. The patch has supports legacy (32-bit) capability userspace, and where possible translates 32-bit capabilities to/from userspace and the VFS to 64-bit kernel space capabilities. If a capability set cannot be compressed into 32-bits for consumption by user space, the system call fails, with -ERANGE. FWIW libcap-2.00 supports this change (and earlier capability formats) http://www.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/ Signed-off-by: Andrew G. Morgan <[EMAIL PROTECTED]> --- fs/nfsd/auth.c | 10 +- fs/proc/array.c | 21 +++- include/linux/capability.h | 222 +++++++++++++++++++++++++++++++------------- kernel/capability.c | 89 ++++++++++++++++-- mm/oom_kill.c | 5 +- security/commoncap.c | 93 +++++++++++++------ security/dummy.c | 17 ++- 7 files changed, 332 insertions(+), 125 deletions(-) diff --git a/fs/nfsd/auth.c b/fs/nfsd/auth.c index 2192805..d13403e 100644 --- a/fs/nfsd/auth.c +++ b/fs/nfsd/auth.c @@ -11,8 +11,6 @@ #include <linux/nfsd/nfsd.h> #include <linux/nfsd/export.h> -#define CAP_NFSD_MASK (CAP_FS_MASK|CAP_TO_MASK(CAP_SYS_RESOURCE)) - int nfsexp_flags(struct svc_rqst *rqstp, struct svc_export *exp) { struct exp_flavor_info *f; @@ -69,10 +67,12 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp) ret = set_current_groups(cred.cr_group_info); put_group_info(cred.cr_group_info); if ((cred.cr_uid)) { - cap_t(current->cap_effective) &= ~CAP_NFSD_MASK; + current->cap_effective = + cap_drop_nfsd_set(current->cap_effective); } else { - cap_t(current->cap_effective) |= (CAP_NFSD_MASK & - current->cap_permitted); + current->cap_effective = + cap_raise_nfsd_set(current->cap_effective, + current->cap_permitted); } return ret; } diff --git a/fs/proc/array.c b/fs/proc/array.c index 3f4d824..303b366 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -286,14 +286,23 @@ static inline char *task_sig(struct task_struct *p, char *buffer) return buffer; } +static char *render_cap_t(const char *header, kernel_cap_t *a, char *buffer) +{ + unsigned __capi; + + buffer += sprintf(buffer, "%s", header); + CAP_FOR_EACH_U32(__capi) { + buffer += sprintf(buffer, "%08x", + a->cap[(_LINUX_CAPABILITY_U32S-1) -__capi]); + } + return buffer + sprintf(buffer, "\n"); +} + static inline char *task_cap(struct task_struct *p, char *buffer) { - return buffer + sprintf(buffer, "CapInh:\t%016x\n" - "CapPrm:\t%016x\n" - "CapEff:\t%016x\n", - cap_t(p->cap_inheritable), - cap_t(p->cap_permitted), - cap_t(p->cap_effective)); + buffer = render_cap_t("CapInh:\t", &p->cap_inheritable, buffer); + buffer = render_cap_t("CapPrm:\t", &p->cap_permitted, buffer); + return render_cap_t("CapEff:\t", &p->cap_effective, buffer); } static inline char *task_context_switch_counts(struct task_struct *p, diff --git a/include/linux/capability.h b/include/linux/capability.h index 7a8d7ad..94663b4 100644 --- a/include/linux/capability.h +++ b/include/linux/capability.h @@ -23,13 +23,20 @@ struct task_struct; kernel might be somewhat backwards compatible, but don't bet on it. */ -/* XXX - Note, cap_t, is defined by POSIX to be an "opaque" pointer to +/* Note, cap_t, is defined by POSIX (draft) to be an "opaque" pointer to a set of three capability sets. The transposition of 3*the following structure to such a composite is better handled in a user library since the draft standard requires the use of malloc/free etc.. */ -#define _LINUX_CAPABILITY_VERSION 0x19980330 +#define _LINUX_CAPABILITY_VERSION_1 0x19980330 +#define _LINUX_CAPABILITY_U32S_1 1 + +#define _LINUX_CAPABILITY_VERSION_2 0x20071026 +#define _LINUX_CAPABILITY_U32S_2 2 + +#define _LINUX_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_2 +#define _LINUX_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_2 typedef struct __user_cap_header_struct { __u32 version; @@ -42,43 +49,42 @@ typedef struct __user_cap_data_struct { __u32 inheritable; } __user *cap_user_data_t; + #define XATTR_CAPS_SUFFIX "capability" #define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX -#define XATTR_CAPS_SZ (3*sizeof(__le32)) #define VFS_CAP_REVISION_MASK 0xFF000000 +#define VFS_CAP_FLAGS_MASK ~VFS_CAP_REVISION_MASK +#define VFS_CAP_FLAGS_EFFECTIVE 0x000001 + #define VFS_CAP_REVISION_1 0x01000000 +#define VFS_CAP_U32_1 1 +#define XATTR_CAPS_SZ_1 (sizeof(__le32)*(1 + 2*VFS_CAP_U32_1)) -#define VFS_CAP_REVISION VFS_CAP_REVISION_1 +#define VFS_CAP_REVISION_2 0x02000000 +#define VFS_CAP_U32_2 2 +#define XATTR_CAPS_SZ_2 (sizeof(__le32)*(1 + 2*VFS_CAP_U32_2)) + +#define XATTR_CAPS_SZ XATTR_CAPS_SZ_2 +#define VFS_CAP_U32 VFS_CAP_U32_2 +#define VFS_CAP_REVISION VFS_CAP_REVISION_2 -#define VFS_CAP_FLAGS_MASK ~VFS_CAP_REVISION_MASK -#define VFS_CAP_FLAGS_EFFECTIVE 0x000001 struct vfs_cap_data { - __u32 magic_etc; /* Little endian */ + __le32 magic_etc; /* Little endian */ struct { - __u32 permitted; /* Little endian */ - __u32 inheritable; /* Little endian */ - } data[1]; + __le32 permitted; /* Little endian */ + __le32 inheritable; /* Little endian */ + } data[VFS_CAP_U32]; }; #ifdef __KERNEL__ -/* #define STRICT_CAP_T_TYPECHECKS */ - -#ifdef STRICT_CAP_T_TYPECHECKS - typedef struct kernel_cap_struct { - __u32 cap; + __u32 cap[_LINUX_CAPABILITY_U32S]; } kernel_cap_t; -#else - -typedef __u32 kernel_cap_t; - -#endif - -#define _USER_CAP_HEADER_SIZE (2*sizeof(__u32)) +#define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct)) #define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t)) #endif @@ -121,10 +127,6 @@ typedef __u32 kernel_cap_t; #define CAP_FSETID 4 -/* Used to decide between falling back on the old suser() or fsuser(). */ - -#define CAP_FS_MASK 0x1f - /* Overrides the restriction that the real or effective user ID of a process sending a signal must match the real or effective user ID of the process receiving the signal. */ @@ -147,8 +149,12 @@ typedef __u32 kernel_cap_t; ** Linux-specific capabilities **/ -/* Transfer any capability in your permitted set to any pid, - remove any capability in your permitted set from any pid */ +/* Without VFS support for capabilities: + * Transfer any capability in your permitted set to any pid, + * remove any capability in your permitted set from any pid + * With VFS support for capabilities (neither of above, but) + * Add any capability to the current process' inheritable set + */ #define CAP_SETPCAP 8 @@ -309,70 +315,154 @@ typedef __u32 kernel_cap_t; #define CAP_SETFCAP 31 +/* + * Bit location of each capability (used by user-space library and kernel) + */ + +#define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */ +#define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */ + #ifdef __KERNEL__ /* * Internal kernel functions only */ -#ifdef STRICT_CAP_T_TYPECHECKS +#define CAP_FOR_EACH_U32(__capi) \ + for (__capi=0; __capi<_LINUX_CAPABILITY_U32S; ++__capi) + +# define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \ + |CAP_TO_MASK(CAP_DAC_OVERRIDE) \ + |CAP_TO_MASK(CAP_DAC_READ_SEARCH) \ + |CAP_TO_MASK(CAP_FOWNER) \ + |CAP_TO_MASK(CAP_FSETID)) + +#if _LINUX_CAPABILITY_U32S != 2 +# error Fix up hand-coded capability macro initializers +#else /* HAND-CODED capability initializers */ + +# define CAP_EMPTY_SET {{ 0, 0 }} +# define CAP_FULL_SET {{ ~0, ~0 }} +# define CAP_INIT_EFF_SET {{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }} +# define CAP_FS_SET {{ CAP_FS_MASK_B0, 0 }} +# define CAP_NFSD_SET {{ CAP_FS_MASK_B0|CAP_TO_MASK(CAP_SYS_RESOURCE), 0 }} + +#endif /* _LINUX_CAPABILITY_U32S != 2 */ + +#define CAP_INIT_INH_SET CAP_EMPTY_SET + +# define cap_clear(c) do { (c) = __cap_empty_set; } while (0) +# define cap_set_full(c) do { (c) = __cap_full_set; } while (0) +# define cap_set_init_eff(c) do { (c) = __cap_init_eff_set; } while (0) + +#define cap_raise(c,flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag)) +#define cap_lower(c,flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag)) +#define cap_raised(c,flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag)) + +#define CAP_BOP_ALL(c, a, b, OP) \ +do { \ + unsigned __capi; \ + CAP_FOR_EACH_U32(__capi) { \ + c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \ + } \ +} while (0) + +#define CAP_UOP_ALL(c, a, OP) \ +do { \ + unsigned __capi; \ + CAP_FOR_EACH_U32(__capi) { \ + c.cap[__capi] = OP a.cap[__capi]; \ + } \ +} while (0) + +static inline kernel_cap_t cap_combine(const kernel_cap_t a, + const kernel_cap_t b) +{ + kernel_cap_t dest; + CAP_BOP_ALL(dest, a, b, |); + return dest; +} -#define to_cap_t(x) { x } -#define cap_t(x) (x).cap +static inline kernel_cap_t cap_intersect(const kernel_cap_t a, + const kernel_cap_t b) +{ + kernel_cap_t dest; + CAP_BOP_ALL(dest, a, b, &); + return dest; +} -#else +static inline kernel_cap_t cap_drop(const kernel_cap_t a, + const kernel_cap_t drop) +{ + kernel_cap_t dest; + CAP_BOP_ALL(dest, a, drop, &~); + return dest; +} -#define to_cap_t(x) (x) -#define cap_t(x) (x) +static inline kernel_cap_t cap_invert(const kernel_cap_t c) +{ + kernel_cap_t dest; + CAP_UOP_ALL(dest, c, ~); + return dest; +} -#endif +static inline int cap_isclear(const kernel_cap_t a) +{ + unsigned __capi; + CAP_FOR_EACH_U32(__capi) { + if (a.cap[__capi] != 0) { + return 0; + } + } + return 1; +} -#define CAP_EMPTY_SET to_cap_t(0) -#define CAP_FULL_SET to_cap_t(~0) -#define CAP_INIT_EFF_SET to_cap_t(~0 & ~CAP_TO_MASK(CAP_SETPCAP)) -#define CAP_INIT_INH_SET to_cap_t(0) +static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set) +{ + kernel_cap_t dest; + dest = cap_drop(a, set); + return cap_isclear(dest); +} -#define CAP_TO_MASK(x) (1 << (x)) -#define cap_raise(c, flag) (cap_t(c) |= CAP_TO_MASK(flag)) -#define cap_lower(c, flag) (cap_t(c) &= ~CAP_TO_MASK(flag)) -#define cap_raised(c, flag) (cap_t(c) & CAP_TO_MASK(flag)) +/* Used to decide between falling back on the old suser() or fsuser(). */ -static inline kernel_cap_t cap_combine(kernel_cap_t a, kernel_cap_t b) +static inline int cap_is_fs_cap(int cap) { - kernel_cap_t dest; - cap_t(dest) = cap_t(a) | cap_t(b); - return dest; + const kernel_cap_t __cap_fs_set = CAP_FS_SET; + return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]); } -static inline kernel_cap_t cap_intersect(kernel_cap_t a, kernel_cap_t b) +static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a) { - kernel_cap_t dest; - cap_t(dest) = cap_t(a) & cap_t(b); - return dest; + const kernel_cap_t __cap_fs_set = CAP_FS_SET; + return cap_drop(a, __cap_fs_set); } -static inline kernel_cap_t cap_drop(kernel_cap_t a, kernel_cap_t drop) +static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a, + const kernel_cap_t permitted) { - kernel_cap_t dest; - cap_t(dest) = cap_t(a) & ~cap_t(drop); - return dest; + const kernel_cap_t __cap_fs_set = CAP_FS_SET; + return cap_combine(a, + cap_intersect(permitted, __cap_fs_set)); } -static inline kernel_cap_t cap_invert(kernel_cap_t c) +static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a) { - kernel_cap_t dest; - cap_t(dest) = ~cap_t(c); - return dest; + const kernel_cap_t __cap_fs_set = CAP_NFSD_SET; + return cap_drop(a, __cap_fs_set); } -#define cap_isclear(c) (!cap_t(c)) -#define cap_issubset(a,set) (!(cap_t(a) & ~cap_t(set))) - -#define cap_clear(c) do { cap_t(c) = 0; } while(0) -#define cap_set_full(c) do { cap_t(c) = ~0; } while(0) -#define cap_mask(c,mask) do { cap_t(c) &= cap_t(mask); } while(0) +static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a, + const kernel_cap_t permitted) +{ + const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET; + return cap_combine(a, + cap_intersect(permitted, __cap_nfsd_set)); +} -#define cap_is_fs_cap(c) (CAP_TO_MASK(c) & CAP_FS_MASK) +extern const kernel_cap_t __cap_empty_set; +extern const kernel_cap_t __cap_full_set; +extern const kernel_cap_t __cap_init_eff_set; int capable(int cap); int __capable(struct task_struct *t, int cap); diff --git a/kernel/capability.c b/kernel/capability.c index efbd9cd..e57d1aa 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -22,6 +22,14 @@ static DEFINE_SPINLOCK(task_capability_lock); /* + * Leveraged for setting/resetting capabilities + */ + +const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET; +const kernel_cap_t __cap_full_set = CAP_FULL_SET; +const kernel_cap_t __cap_init_eff_set = CAP_INIT_EFF_SET; + +/* * For sys_getproccap() and sys_setproccap(), any of the three * capability set pointers may be NULL -- indicating that that set is * uninteresting and/or not to be changed. @@ -38,16 +46,31 @@ static DEFINE_SPINLOCK(task_capability_lock); */ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr) { + static int warned = 0; int ret = 0; pid_t pid; __u32 version; struct task_struct *target; - struct __user_cap_data_struct data; + unsigned tocopy; + kernel_cap_t pE, pI, pP; if (get_user(version, &header->version)) return -EFAULT; - if (version != _LINUX_CAPABILITY_VERSION) { + switch (version) { + case _LINUX_CAPABILITY_VERSION_1: + if (warned < 5) { + warned++; + printk(KERN_INFO + "warning: process `%s' gets w/ old libcap\n", + current->comm); + } + tocopy = _LINUX_CAPABILITY_U32S_1; + break; + case _LINUX_CAPABILITY_VERSION_2: + tocopy = _LINUX_CAPABILITY_U32S_2; + break; + default: if (put_user(_LINUX_CAPABILITY_VERSION, &header->version)) return -EFAULT; return -EINVAL; @@ -71,14 +94,34 @@ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr) } else target = current; - ret = security_capget(target, &data.effective, &data.inheritable, &data.permitted); + ret = security_capget(target, &pE, &pI, &pP); out: read_unlock(&tasklist_lock); spin_unlock(&task_capability_lock); - if (!ret && copy_to_user(dataptr, &data, sizeof data)) - return -EFAULT; + if (!ret) { + struct __user_cap_data_struct kdata[_LINUX_CAPABILITY_U32S]; + unsigned i; + + for (i=0; i < tocopy; i++) { + kdata[i].effective = pE.cap[i]; + kdata[i].permitted = pP.cap[i]; + kdata[i].inheritable = pI.cap[i]; + } + while (i < _LINUX_CAPABILITY_U32S) { + if (pE.cap[i] || pP.cap[i] || pP.cap[i]) { + /* Cannot represent w/ legacy structure */ + return -ERANGE; + } + i++; + } + + if (copy_to_user(dataptr, kdata, tocopy + * sizeof(struct __user_cap_data_struct))) { + return -EFAULT; + } + } return ret; } @@ -167,6 +210,9 @@ static inline int cap_set_all(kernel_cap_t *effective, */ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) { + static int warned = 0; + struct __user_cap_data_struct kdata[_LINUX_CAPABILITY_U32S]; + unsigned i, tocopy; kernel_cap_t inheritable, permitted, effective; __u32 version; struct task_struct *target; @@ -176,7 +222,20 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) if (get_user(version, &header->version)) return -EFAULT; - if (version != _LINUX_CAPABILITY_VERSION) { + switch (version) { + case _LINUX_CAPABILITY_VERSION_1: + if (warned < 5) { + warned++; + printk(KERN_INFO + "warning: process `%s' sets w/ old libcap\n", + current->comm); + } + tocopy = _LINUX_CAPABILITY_U32S_1; + break; + case _LINUX_CAPABILITY_VERSION_2: + tocopy = _LINUX_CAPABILITY_U32S_2; + break; + default: if (put_user(_LINUX_CAPABILITY_VERSION, &header->version)) return -EFAULT; return -EINVAL; @@ -188,10 +247,22 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) if (pid && pid != task_pid_vnr(current) && !capable(CAP_SETPCAP)) return -EPERM; - if (copy_from_user(&effective, &data->effective, sizeof(effective)) || - copy_from_user(&inheritable, &data->inheritable, sizeof(inheritable)) || - copy_from_user(&permitted, &data->permitted, sizeof(permitted))) + if (copy_from_user(&kdata, data, tocopy + * sizeof(struct __user_cap_data_struct))) { return -EFAULT; + } + + for (i=0; i < tocopy; i++) { + effective.cap[i] = kdata[i].effective; + permitted.cap[i] = kdata[i].permitted; + inheritable.cap[i] = kdata[i].inheritable; + } + while (i < _LINUX_CAPABILITY_U32S) { + effective.cap[i] = 0; + permitted.cap[i] = 0; + inheritable.cap[i] = 0; + i++; + } spin_lock(&task_capability_lock); read_lock(&tasklist_lock); diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 1f4b693..8017bb7 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -128,8 +128,7 @@ unsigned long badness(struct task_struct *p, unsigned long uptime, * Superuser processes are usually more important, so we make it * less likely that we kill those. */ - if (cap_t(p->cap_effective) & CAP_TO_MASK(CAP_SYS_ADMIN) || - p->uid == 0 || p->euid == 0) + if (__capable(p, CAP_SYS_ADMIN) || p->uid == 0 || p->euid == 0) points /= 4; /* @@ -138,7 +137,7 @@ unsigned long badness(struct task_struct *p, unsigned long uptime, * tend to only have this flag set on applications they think * of as important. */ - if (cap_t(p->cap_effective) & CAP_TO_MASK(CAP_SYS_RAWIO)) + if (__capable(p, CAP_SYS_RAWIO)) points /= 4; /* diff --git a/security/commoncap.c b/security/commoncap.c index 43f9027..dd63129 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -1,4 +1,4 @@ -/* Common capabilities, needed by capability.o and root_plug.o +/* Common capabilities, needed by capability.o and root_plug.o * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -87,9 +87,9 @@ int cap_capget (struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted) { /* Derived from kernel/capability.c:sys_capget. */ - *effective = cap_t (target->cap_effective); - *inheritable = cap_t (target->cap_inheritable); - *permitted = cap_t (target->cap_permitted); + *effective = target->cap_effective; + *inheritable = target->cap_inheritable; + *permitted = target->cap_permitted; return 0; } @@ -190,28 +190,54 @@ int cap_inode_killpriv(struct dentry *dentry) return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS); } -static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm, - int size) +static inline int cap_from_disk(struct vfs_cap_data *caps, + struct linux_binprm *bprm, unsigned size) { __u32 magic_etc; + unsigned tocopy, i; - if (size != XATTR_CAPS_SZ) + if (size < sizeof(magic_etc)) { return -EINVAL; + } - magic_etc = le32_to_cpu(caps[0]); + magic_etc = le32_to_cpu(caps->magic_etc); switch ((magic_etc & VFS_CAP_REVISION_MASK)) { - case VFS_CAP_REVISION: - if (magic_etc & VFS_CAP_FLAGS_EFFECTIVE) - bprm->cap_effective = true; - else - bprm->cap_effective = false; - bprm->cap_permitted = to_cap_t( le32_to_cpu(caps[1]) ); - bprm->cap_inheritable = to_cap_t( le32_to_cpu(caps[2]) ); - return 0; + case VFS_CAP_REVISION_1: + if (size != XATTR_CAPS_SZ_1) { + return -EINVAL; + } + tocopy = VFS_CAP_U32_1; + break; + case VFS_CAP_REVISION_2: + if (size != XATTR_CAPS_SZ_2) { + return -EINVAL; + } + tocopy = VFS_CAP_U32_2; + break; default: return -EINVAL; } + + if (magic_etc & VFS_CAP_FLAGS_EFFECTIVE) { + bprm->cap_effective = true; + } else { + bprm->cap_effective = false; + } + + for (i=0; i < tocopy; ++i) { + bprm->cap_permitted.cap[i] = + le32_to_cpu(caps->data[i].permitted); + bprm->cap_inheritable.cap[i] = + le32_to_cpu(caps->data[i].inheritable); + } + while (i < VFS_CAP_U32) { + bprm->cap_permitted.cap[i] = 0; + bprm->cap_inheritable.cap[i] = 0; + i++; + } + + return 0; } /* Locate any VFS capabilities: */ @@ -219,7 +245,7 @@ static int get_file_caps(struct linux_binprm *bprm) { struct dentry *dentry; int rc = 0; - __le32 v1caps[XATTR_CAPS_SZ]; + struct vfs_cap_data vcaps; struct inode *inode; if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) { @@ -232,8 +258,8 @@ static int get_file_caps(struct linux_binprm *bprm) if (!inode->i_op || !inode->i_op->getxattr) goto out; - rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, &v1caps, - XATTR_CAPS_SZ); + rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, &vcaps, + XATTR_CAPS_SZ); if (rc == -ENODATA || rc == -EOPNOTSUPP) { /* no data, that's ok */ rc = 0; @@ -242,7 +268,7 @@ static int get_file_caps(struct linux_binprm *bprm) if (rc < 0) goto out; - rc = cap_from_disk(v1caps, bprm, rc); + rc = cap_from_disk(&vcaps, bprm, rc); if (rc) printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n", __FUNCTION__, rc, bprm->filename); @@ -337,8 +363,11 @@ void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe) * capability rules */ if (!is_global_init(current)) { current->cap_permitted = new_permitted; - current->cap_effective = bprm->cap_effective ? - new_permitted : 0; + if (bprm->cap_effective) { + current->cap_effective = new_permitted; + } else { + cap_clear(current->cap_effective); + } } /* AUD: Audit candidate if current->cap_effective is set */ @@ -460,13 +489,17 @@ int cap_task_post_setuid (uid_t old_ruid, uid_t old_euid, uid_t old_suid, if (!issecure (SECURE_NO_SETUID_FIXUP)) { if (old_fsuid == 0 && current->fsuid != 0) { - cap_t (current->cap_effective) &= - ~CAP_FS_MASK; + current->cap_effective = + cap_drop_fs_set( + current->cap_effective + ); } if (old_fsuid != 0 && current->fsuid == 0) { - cap_t (current->cap_effective) |= - (cap_t (current->cap_permitted) & - CAP_FS_MASK); + current->cap_effective = + cap_raise_fs_set( + current->cap_effective, + current->cap_permitted + ); } } break; @@ -557,9 +590,9 @@ int cap_task_kill(struct task_struct *p, struct siginfo *info, void cap_task_reparent_to_init (struct task_struct *p) { - p->cap_effective = CAP_INIT_EFF_SET; - p->cap_inheritable = CAP_INIT_INH_SET; - p->cap_permitted = CAP_FULL_SET; + cap_set_init_eff(p->cap_effective); + cap_clear(p->cap_inheritable); + cap_set_full(p->cap_permitted); p->keep_capabilities = 0; return; } diff --git a/security/dummy.c b/security/dummy.c index 6d895ad..bd7e5b3 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -36,14 +36,19 @@ static int dummy_ptrace (struct task_struct *parent, struct task_struct *child) static int dummy_capget (struct task_struct *target, kernel_cap_t * effective, kernel_cap_t * inheritable, kernel_cap_t * permitted) { - *effective = *inheritable = *permitted = 0; if (target->euid == 0) { - *permitted |= (~0 & ~CAP_FS_MASK); - *effective |= (~0 & ~CAP_TO_MASK(CAP_SETPCAP) & ~CAP_FS_MASK); + cap_set_full(*permitted); + cap_set_init_eff(*effective); + } else { + cap_clear(*permitted); + cap_clear(*effective); } - if (target->fsuid == 0) { - *permitted |= CAP_FS_MASK; - *effective |= CAP_FS_MASK; + + cap_clear(*inheritable); + + if (target->fsuid != 0) { + *permitted = cap_drop_fs_set(*permitted); + *effective = cap_drop_fs_set(*effective); } return 0; } -- 1.5.1.3
