/* * FUSE: Filesystem in Userspace * Copyright (C) 2001-2016 Miklos Szeredi * * This program can be distributed under the terms of the GNU GPL. * See the file COPYING. */ #include "fuse_i.h" #include #include int fuse_setxattr(struct inode *inode, const char *name, const void *value, size_t size, int flags) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); struct fuse_setxattr_in inarg; int err; if (fc->no_setxattr) return -EOPNOTSUPP; memset(&inarg, 0, sizeof(inarg)); inarg.size = size; inarg.flags = flags; args.in.h.opcode = FUSE_SETXATTR; args.in.h.nodeid = get_node_id(inode); args.in.numargs = 3; args.in.args[0].size = sizeof(inarg); args.in.args[0].value = &inarg; args.in.args[1].size = strlen(name) + 1; args.in.args[1].value = name; args.in.args[2].size = size; args.in.args[2].value = value; err = fuse_simple_request(fc, &args); if (err == -ENOSYS) { fc->no_setxattr = 1; err = -EOPNOTSUPP; } if (!err) { fuse_invalidate_attr(inode); fuse_update_ctime(inode); } return err; } ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value, size_t size) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); struct fuse_getxattr_in inarg; struct fuse_getxattr_out outarg; ssize_t ret; if (fc->no_getxattr) return -EOPNOTSUPP; memset(&inarg, 0, sizeof(inarg)); inarg.size = size; args.in.h.opcode = FUSE_GETXATTR; args.in.h.nodeid = get_node_id(inode); args.in.numargs = 2; args.in.args[0].size = sizeof(inarg); args.in.args[0].value = &inarg; args.in.args[1].size = strlen(name) + 1; args.in.args[1].value = name; /* This is really two different operations rolled into one */ args.out.numargs = 1; if (size) { args.out.argvar = 1; args.out.args[0].size = size; args.out.args[0].value = value; } else { args.out.args[0].size = sizeof(outarg); args.out.args[0].value = &outarg; } ret = fuse_simple_request(fc, &args); if (!ret && !size) ret = min_t(ssize_t, outarg.size, XATTR_SIZE_MAX); if (ret == -ENOSYS) { fc->no_getxattr = 1; ret = -EOPNOTSUPP; } return ret; } static int fuse_verify_xattr_list(char *list, size_t size) { size_t origsize = size; while (size) { size_t thislen = strnlen(list, size); if (!thislen || thislen == size) return -EIO; size -= thislen + 1; list += thislen + 1; } return origsize; } ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) { struct inode *inode = d_inode(entry); struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); struct fuse_getxattr_in inarg; struct fuse_getxattr_out outarg; ssize_t ret; if (!fuse_allow_current_process(fc)) return -EACCES; if (fc->no_listxattr) return -EOPNOTSUPP; memset(&inarg, 0, sizeof(inarg)); inarg.size = size; args.in.h.opcode = FUSE_LISTXATTR; args.in.h.nodeid = get_node_id(inode); args.in.numargs = 1; args.in.args[0].size = sizeof(inarg); args.in.args[0].value = &inarg; /* This is really two different operations rolled into one */ args.out.numargs = 1; if (size) { args.out.argvar = 1; args.out.args[0].size = size; args.out.args[0].value = list; } else { args.out.args[0].size = sizeof(outarg); args.out.args[0].value = &outarg; } ret = fuse_simple_request(fc, &args); if (!ret && !size) ret = min_t(ssize_t, outarg.size, XATTR_LIST_MAX); if (ret > 0 && size) ret = fuse_verify_xattr_list(list, ret); if (ret == -ENOSYS) { fc->no_listxattr = 1; ret = -EOPNOTSUPP; } return ret; } int fuse_removexattr(struct inode *inode, const char *name) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); int err; if (fc->no_removexattr) return -EOPNOTSUPP; args.in.h.opcode = FUSE_REMOVEXATTR; args.in.h.nodeid = get_node_id(inode); args.in.numargs = 1; args.in.args[0].size = strlen(name) + 1; args.in.args[0].value = name; err = fuse_simple_request(fc, &args); if (err == -ENOSYS) { fc->no_removexattr = 1; err = -EOPNOTSUPP; } if (!err) { fuse_invalidate_attr(inode); fuse_update_ctime(inode); } return err; } static int fuse_xattr_get(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *value, size_t size) { return fuse_getxattr(inode, name, value, size); } static int fuse_xattr_set(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, const void *value, size_t size, int flags) { if (!value) return fuse_removexattr(inode, name); return fuse_setxattr(inode, name, value, size, flags); } static const struct xattr_handler fuse_xattr_handler = { .prefix = "", .get = fuse_xattr_get, .set = fuse_xattr_set, }; const struct xattr_handler *fuse_xattr_handlers[] = { &fuse_xattr_handler, NULL }; const struct xattr_handler *fuse_acl_xattr_handlers[] = { &posix_acl_access_xattr_handler, &posix_acl_default_xattr_handler, &fuse_xattr_handler, NULL }; tion.org>2017-01-29 13:50:06 -0800 committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800 commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch) tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /include/scsi/viosrp.h parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/scsi/viosrp.h')