kernel/linux.git, branch v4.9.295

Linux 4.9.295

2021-12-29T11:14:49+00:00

Link: https://lore.kernel.org/r/20211227151316.558965545@linuxfoundation.org Tested-by: Florian Fainelli Tested-by: Guenter Roeck Tested-by: Linux Kernel Functional Testing Tested-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman

phonet/pep: refuse to enable an unbound pipe

2021-12-29T11:14:49+00:00

commit 75a2f31520095600f650597c0ac41f48b5ba0068 upstream. This ioctl() implicitly assumed that the socket was already bound to a valid local socket name, i.e. Phonet object. If the socket was not bound, two separate problems would occur: 1) We'd send an pipe enablement request with an invalid source object. 2) Later socket calls could BUG on the socket unexpectedly being connected yet not bound to a valid object. Reported-by: syzbot+2dc91e7fc3dea88b1e8a@syzkaller.appspotmail.com Signed-off-by: Rémi Denis-Courmont Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

hamradio: improve the incomplete fix to avoid NPD

2021-12-29T11:14:49+00:00

commit b2f37aead1b82a770c48b5d583f35ec22aabb61e upstream. The previous commit 3e0588c291d6 ("hamradio: defer ax25 kfree after unregister_netdev") reorder the kfree operations and unregister_netdev operation to prevent UAF. This commit improves the previous one by also deferring the nullify of the ax->tty pointer. Otherwise, a NULL pointer dereference bug occurs. Partial of the stack trace is shown below. BUG: kernel NULL pointer dereference, address: 0000000000000538 RIP: 0010:ax_xmit+0x1f9/0x400 ... Call Trace: dev_hard_start_xmit+0xec/0x320 sch_direct_xmit+0xea/0x240 __qdisc_run+0x166/0x5c0 __dev_queue_xmit+0x2c7/0xaf0 ax25_std_establish_data_link+0x59/0x60 ax25_connect+0x3a0/0x500 ? security_socket_connect+0x2b/0x40 __sys_connect+0x96/0xc0 ? __hrtimer_init+0xc0/0xc0 ? common_nsleep+0x2e/0x50 ? switch_fpu_return+0x139/0x1a0 __x64_sys_connect+0x11/0x20 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The crash point is shown as below static void ax_encaps(...) { ... set_bit(TTY_DO_WRITE_WAKEUP, &ax->tty->flags); // ax->tty = NULL! ... } By placing the nullify action after the unregister_netdev, the ax->tty pointer won't be assigned as NULL net_device framework layer is well synchronized. Signed-off-by: Lin Ma Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

hamradio: defer ax25 kfree after unregister_netdev

2021-12-29T11:14:49+00:00

commit 3e0588c291d6ce225f2b891753ca41d45ba42469 upstream. There is a possible race condition (use-after-free) like below (USE) | (FREE) ax25_sendmsg | ax25_queue_xmit | dev_queue_xmit | __dev_queue_xmit | __dev_xmit_skb | sch_direct_xmit | ... xmit_one | netdev_start_xmit | tty_ldisc_kill __netdev_start_xmit | mkiss_close ax_xmit | kfree ax_encaps | | Even though there are two synchronization primitives before the kfree: 1. wait_for_completion(&ax->dead). This can prevent the race with routines from mkiss_ioctl. However, it cannot stop the routine coming from upper layer, i.e., the ax25_sendmsg. 2. netif_stop_queue(ax->dev). It seems that this line of code aims to halt the transmit queue but it fails to stop the routine that already being xmit. This patch reorder the kfree after the unregister_netdev to avoid the possible UAF as the unregister_netdev() is well synchronized and won't return if there is a running routine. Signed-off-by: Lin Ma Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ax25: NPD bug when detaching AX25 device

2021-12-29T11:14:49+00:00

commit 1ade48d0c27d5da1ccf4b583d8c5fc8b534a3ac8 upstream. The existing cleanup routine implementation is not well synchronized with the syscall routine. When a device is detaching, below race could occur. static int ax25_sendmsg(...) { ... lock_sock() ax25 = sk_to_ax25(sk); if (ax25->ax25_dev == NULL) // CHECK ... ax25_queue_xmit(skb, ax25->ax25_dev->dev); // USE ... } static void ax25_kill_by_device(...) { ... if (s->ax25_dev == ax25_dev) { s->ax25_dev = NULL; ... } Other syscall functions like ax25_getsockopt, ax25_getname, ax25_info_show also suffer from similar races. To fix them, this patch introduce lock_sock() into ax25_kill_by_device in order to guarantee that the nullify action in cleanup routine cannot proceed when another socket request is pending. Signed-off-by: Hanjie Wu Signed-off-by: Lin Ma Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

hwmon: (lm90) Do not report 'busy' status bit as alarm

2021-12-29T11:14:49+00:00

commit cdc5287acad9ede121924a9c9313544b80d15842 upstream. Bit 7 of the status register indicates that the chip is busy doing a conversion. It does not indicate an alarm status. Stop reporting it as alarm status bit. Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

ARM: 9169/1: entry: fix Thumb2 bug in iWMMXt exception handling

2021-12-29T11:14:49+00:00

commit 8536a5ef886005bc443c2da9b842d69fd3d7647f upstream. The Thumb2 version of the FP exception handling entry code treats the register holding the CP number (R8) differently, resulting in the iWMMXT CP number check to be incorrect. Fix this by unifying the ARM and Thumb2 code paths, and switch the order of the additions of the TI_USED_CP offset and the shifted CP index. Cc: Fixes: b86040a59feb ("Thumb-2: Implementation of the unified start-up and exceptions code") Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

x86/pkey: Fix undefined behaviour with PKRU_WD_BIT

2021-12-29T11:14:48+00:00

commit 57690554abe135fee81d6ac33cc94d75a7e224bb upstream. Both __pkru_allows_write() and arch_set_user_pkey_access() shift PKRU_WD_BIT (a signed constant) by up to 30 bits, hitting the sign bit. Use unsigned constants instead. Clearly pkey 15 has not been used in combination with UBSAN yet. Noticed by code inspection only. I can't actually provoke the compiler into generating incorrect logic as far as this shift is concerned. [ dhansen: add stable@ tag, plus minor changelog massaging, For anyone doing backports, these #defines were in arch/x86/include/asm/pgtable.h before 784a46618f6. ] Fixes: 33a709b25a76 ("mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys") Signed-off-by: Andrew Cooper Signed-off-by: Dave Hansen Signed-off-by: Borislav Petkov Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20211216000856.4480-1-andrew.cooper3@citrix.com Signed-off-by: Greg Kroah-Hartman

ALSA: drivers: opl3: Fix incorrect use of vp->state

2021-12-29T11:14:48+00:00

commit 2dee54b289fbc810669a1b2b8a0887fa1c9a14d7 upstream. Static analysis with scan-build has found an assignment to vp2 that is never used. It seems that the check on vp->state > 0 should be actually on vp2->state instead. Fix this. This dates back to 2002, I found the offending commit from the git history git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git, commit 91e39521bbf6 ("[PATCH] ALSA patch for 2.5.4") Signed-off-by: Colin Ian King Cc: Link: https://lore.kernel.org/r/20211212172025.470367-1-colin.i.king@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: jack: Check the return value of kstrdup()

2021-12-29T11:14:48+00:00

commit c01c1db1dc632edafb0dff32d40daf4f9c1a4e19 upstream. kstrdup() can return NULL, it is better to check the return value of it. Signed-off-by: Xiaoke Wang Cc: Link: https://lore.kernel.org/r/tencent_094816F3522E0DC704056C789352EBBF0606@qq.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman