From ef81ee9855d6c605ed6090a8018c78572cc68b5c Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 14 Nov 2008 10:38:37 +1100 Subject: CRED: Wrap task credential accesses in the IA64 arch Wrap access to task credentials so that they can be separated more easily from the task_struct during the introduction of COW creds. Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id(). Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more sense to use RCU directly rather than a convenient wrapper; these will be addressed by later patches. Signed-off-by: David Howells Reviewed-by: James Morris Acked-by: Serge Hallyn Cc: Tony Luck Cc: linux-ia64@vger.kernel.org Signed-off-by: James Morris --- arch/ia64/kernel/mca_drv.c | 2 +- arch/ia64/kernel/perfmon.c | 23 +++++++++++++---------- arch/ia64/kernel/signal.c | 4 ++-- 3 files changed, 16 insertions(+), 13 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/kernel/mca_drv.c b/arch/ia64/kernel/mca_drv.c index fab1d21a4f2..f94aaa86933 100644 --- a/arch/ia64/kernel/mca_drv.c +++ b/arch/ia64/kernel/mca_drv.c @@ -158,7 +158,7 @@ mca_handler_bh(unsigned long paddr, void *iip, unsigned long ipsr) ia64_mlogbuf_dump(); printk(KERN_ERR "OS_MCA: process [cpu %d, pid: %d, uid: %d, " "iip: %p, psr: 0x%lx,paddr: 0x%lx](%s) encounters MCA.\n", - raw_smp_processor_id(), current->pid, current->uid, + raw_smp_processor_id(), current->pid, current_uid(), iip, ipsr, paddr, current->comm); spin_lock(&mca_bh_lock); diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c index 6543a5547c8..dd38db46a77 100644 --- a/arch/ia64/kernel/perfmon.c +++ b/arch/ia64/kernel/perfmon.c @@ -2220,8 +2220,8 @@ pfm_alloc_file(pfm_context_t *ctx) DPRINT(("new inode ino=%ld @%p\n", inode->i_ino, inode)); inode->i_mode = S_IFCHR|S_IRUGO; - inode->i_uid = current->fsuid; - inode->i_gid = current->fsgid; + inode->i_uid = current_fsuid(); + inode->i_gid = current_fsgid(); sprintf(name, "[%lu]", inode->i_ino); this.name = name; @@ -2399,22 +2399,25 @@ error_kmem: static int pfm_bad_permissions(struct task_struct *task) { + uid_t uid = current_uid(); + gid_t gid = current_gid(); + /* inspired by ptrace_attach() */ DPRINT(("cur: uid=%d gid=%d task: euid=%d suid=%d uid=%d egid=%d sgid=%d\n", - current->uid, - current->gid, + uid, + gid, task->euid, task->suid, task->uid, task->egid, task->sgid)); - return ((current->uid != task->euid) - || (current->uid != task->suid) - || (current->uid != task->uid) - || (current->gid != task->egid) - || (current->gid != task->sgid) - || (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE); + return (uid != task->euid) + || (uid != task->suid) + || (uid != task->uid) + || (gid != task->egid) + || (gid != task->sgid) + || (gid != task->gid)) && !capable(CAP_SYS_PTRACE); } static int diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c index e12500a9c44..e1821ca4c7d 100644 --- a/arch/ia64/kernel/signal.c +++ b/arch/ia64/kernel/signal.c @@ -229,7 +229,7 @@ ia64_rt_sigreturn (struct sigscratch *scr) si.si_errno = 0; si.si_code = SI_KERNEL; si.si_pid = task_pid_vnr(current); - si.si_uid = current->uid; + si.si_uid = current_uid(); si.si_addr = sc; force_sig_info(SIGSEGV, &si, current); return retval; @@ -326,7 +326,7 @@ force_sigsegv_info (int sig, void __user *addr) si.si_errno = 0; si.si_code = SI_KERNEL; si.si_pid = task_pid_vnr(current); - si.si_uid = current->uid; + si.si_uid = current_uid(); si.si_addr = addr; force_sig_info(SIGSEGV, &si, current); return 0; -- cgit v1.2.3 From b6dff3ec5e116e3af6f537d4caedcad6b9e5082a Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 14 Nov 2008 10:39:16 +1100 Subject: CRED: Separate task security context from task_struct Separate the task security context from task_struct. At this point, the security data is temporarily embedded in the task_struct with two pointers pointing to it. Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in entry.S via asm-offsets. With comment fixes Signed-off-by: Marc Dionne Signed-off-by: David Howells Acked-by: James Morris Acked-by: Serge Hallyn Signed-off-by: James Morris --- arch/ia64/ia32/sys_ia32.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/ia32/sys_ia32.c b/arch/ia64/ia32/sys_ia32.c index 5e92ae00bdb..2445a9d3488 100644 --- a/arch/ia64/ia32/sys_ia32.c +++ b/arch/ia64/ia32/sys_ia32.c @@ -1772,20 +1772,20 @@ sys32_getgroups16 (int gidsetsize, short __user *grouplist) if (gidsetsize < 0) return -EINVAL; - get_group_info(current->group_info); - i = current->group_info->ngroups; + get_group_info(current->cred->group_info); + i = current->cred->group_info->ngroups; if (gidsetsize) { if (i > gidsetsize) { i = -EINVAL; goto out; } - if (groups16_to_user(grouplist, current->group_info)) { + if (groups16_to_user(grouplist, current->cred->group_info)) { i = -EFAULT; goto out; } } out: - put_group_info(current->group_info); + put_group_info(current->cred->group_info); return i; } -- cgit v1.2.3 From 86a264abe542cfececb4df129bc45a0338d8cdb9 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 14 Nov 2008 10:39:18 +1100 Subject: CRED: Wrap current->cred and a few other accessors Wrap current->cred and a few other accessors to hide their actual implementation. Signed-off-by: David Howells Acked-by: James Morris Acked-by: Serge Hallyn Signed-off-by: James Morris --- arch/ia64/ia32/sys_ia32.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/ia32/sys_ia32.c b/arch/ia64/ia32/sys_ia32.c index 2445a9d3488..16ef61a91d9 100644 --- a/arch/ia64/ia32/sys_ia32.c +++ b/arch/ia64/ia32/sys_ia32.c @@ -1767,25 +1767,24 @@ groups16_from_user(struct group_info *group_info, short __user *grouplist) asmlinkage long sys32_getgroups16 (int gidsetsize, short __user *grouplist) { + const struct cred *cred = current_cred(); int i; if (gidsetsize < 0) return -EINVAL; - get_group_info(current->cred->group_info); - i = current->cred->group_info->ngroups; + i = cred->group_info->ngroups; if (gidsetsize) { if (i > gidsetsize) { i = -EINVAL; goto out; } - if (groups16_to_user(grouplist, current->cred->group_info)) { + if (groups16_to_user(grouplist, cred->group_info)) { i = -EFAULT; goto out; } } out: - put_group_info(current->cred->group_info); return i; } -- cgit v1.2.3 From c69e8d9c01db2adc503464993c358901c9af9de4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 14 Nov 2008 10:39:19 +1100 Subject: CRED: Use RCU to access another task's creds and to release a task's own creds Use RCU to access another task's creds and to release a task's own creds. This means that it will be possible for the credentials of a task to be replaced without another task (a) requiring a full lock to read them, and (b) seeing deallocated memory. Signed-off-by: David Howells Acked-by: James Morris Acked-by: Serge Hallyn Signed-off-by: James Morris --- arch/ia64/kernel/perfmon.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c index dd38db46a77..0e499757309 100644 --- a/arch/ia64/kernel/perfmon.c +++ b/arch/ia64/kernel/perfmon.c @@ -2399,25 +2399,33 @@ error_kmem: static int pfm_bad_permissions(struct task_struct *task) { + const struct cred *tcred; uid_t uid = current_uid(); gid_t gid = current_gid(); + int ret; + + rcu_read_lock(); + tcred = __task_cred(task); /* inspired by ptrace_attach() */ DPRINT(("cur: uid=%d gid=%d task: euid=%d suid=%d uid=%d egid=%d sgid=%d\n", uid, gid, - task->euid, - task->suid, - task->uid, - task->egid, - task->sgid)); - - return (uid != task->euid) - || (uid != task->suid) - || (uid != task->uid) - || (gid != task->egid) - || (gid != task->sgid) - || (gid != task->gid)) && !capable(CAP_SYS_PTRACE); + tcred->euid, + tcred->suid, + tcred->uid, + tcred->egid, + tcred->sgid)); + + ret = ((uid != tcred->euid) + || (uid != tcred->suid) + || (uid != tcred->uid) + || (gid != tcred->egid) + || (gid != tcred->sgid) + || (gid != tcred->gid)) && !capable(CAP_SYS_PTRACE); + + rcu_read_unlock(); + return ret; } static int -- cgit v1.2.3