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authorYunhong Jiang <yunhong.jiang@linux.intel.com>2017-03-08 23:13:28 -0800
committerYunhong Jiang <yunhong.jiang@linux.intel.com>2017-03-08 23:36:15 -0800
commit52f993b8e89487ec9ee15a7fb4979e0f09a45b27 (patch)
treed65304486afe0bea4a311c783c0d72791c8c0aa2 /kernel/fs/exec.c
parentc189ccac5702322ed843fe17057035b7222a59b6 (diff)
Upgrade to 4.4.50-rt62
The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it to 4.4.50-rt62. The command to achieve it is: a) Clone a git repo from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git b) Get the diff between this two changesets: git diff 640eca2901f3435e616157b11379d3223a44b391 705619beeea1b0b48219a683fd1a901a86fdaf5e where the two commits are: [yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only 640eca2901f3435e616157b11379d3223a44b391 640eca2901f3 v4.4.6-rt14 localversion-rt [yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only 705619beeea1b0b48219a683fd1a901a86fdaf5e 705619beeea1 Linux 4.4.50-rt62 localversion-rt c) One patch has been backported thus revert the patch before applying. filterdiff -p1 -x scripts/package/Makefile ~/tmp/v4.4.6-rt14-4.4.50-rt62.diff |patch -p1 --dry-run Upstream status: backport Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01 Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>
Diffstat (limited to 'kernel/fs/exec.c')
-rw-r--r--kernel/fs/exec.c32
1 files changed, 27 insertions, 5 deletions
diff --git a/kernel/fs/exec.c b/kernel/fs/exec.c
index e7760b7b6..74962ac0a 100644
--- a/kernel/fs/exec.c
+++ b/kernel/fs/exec.c
@@ -19,7 +19,7 @@
* current->executable is only used by the procfs. This allows a dispatch
* table to check for several different types of binary formats. We keep
* trying until we recognize the file or we run out of supported binary
- * formats.
+ * formats.
*/
#include <linux/slab.h>
@@ -56,6 +56,7 @@
#include <linux/pipe_fs_i.h>
#include <linux/oom.h>
#include <linux/compat.h>
+#include <linux/user_namespace.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
@@ -1116,6 +1117,13 @@ int flush_old_exec(struct linux_binprm * bprm)
flush_thread();
current->personality &= ~bprm->per_clear;
+ /*
+ * We have to apply CLOEXEC before we change whether the process is
+ * dumpable (in setup_new_exec) to avoid a race with a process in userspace
+ * trying to access the should-be-closed file descriptors of a process
+ * undergoing exec(2).
+ */
+ do_close_on_exec(current->files);
return 0;
out:
@@ -1125,8 +1133,22 @@ EXPORT_SYMBOL(flush_old_exec);
void would_dump(struct linux_binprm *bprm, struct file *file)
{
- if (inode_permission(file_inode(file), MAY_READ) < 0)
+ struct inode *inode = file_inode(file);
+ if (inode_permission(inode, MAY_READ) < 0) {
+ struct user_namespace *old, *user_ns;
bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
+
+ /* Ensure mm->user_ns contains the executable */
+ user_ns = old = bprm->mm->user_ns;
+ while ((user_ns != &init_user_ns) &&
+ !privileged_wrt_inode_uidgid(user_ns, inode))
+ user_ns = user_ns->parent;
+
+ if (old != user_ns) {
+ bprm->mm->user_ns = get_user_ns(user_ns);
+ put_user_ns(old);
+ }
+ }
}
EXPORT_SYMBOL(would_dump);
@@ -1156,7 +1178,6 @@ void setup_new_exec(struct linux_binprm * bprm)
!gid_eq(bprm->cred->gid, current_egid())) {
current->pdeath_signal = 0;
} else {
- would_dump(bprm, bprm->file);
if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)
set_dumpable(current->mm, suid_dumpable);
}
@@ -1165,7 +1186,6 @@ void setup_new_exec(struct linux_binprm * bprm)
group */
current->self_exec_id++;
flush_signal_handlers(current, 0);
- do_close_on_exec(current->files);
}
EXPORT_SYMBOL(setup_new_exec);
@@ -1256,7 +1276,7 @@ static void check_unsafe_exec(struct linux_binprm *bprm)
unsigned n_fs;
if (p->ptrace) {
- if (p->ptrace & PT_PTRACE_CAP)
+ if (ptracer_capable(p, current_user_ns()))
bprm->unsafe |= LSM_UNSAFE_PTRACE_CAP;
else
bprm->unsafe |= LSM_UNSAFE_PTRACE;
@@ -1589,6 +1609,8 @@ static int do_execveat_common(int fd, struct filename *filename,
if (retval < 0)
goto out;
+ would_dump(bprm, bprm->file);
+
retval = exec_binprm(bprm);
if (retval < 0)
goto out;