Daniel Borkmann f6fadff33e tls: fix NULL pointer dereference on poll ... While hacking on kTLS, I ran into the following panic from an unprivileged netserver / netperf TCP session: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD 800000037f378067 P4D 800000037f378067 PUD 3c0e61067 PMD 0 Oops: 0010 [#1] SMP KASAN PTI CPU: 1 PID: 2289 Comm: netserver Not tainted 4.17.0+ #139 Hardware name: LENOVO 20FBCTO1WW/20FBCTO1WW, BIOS N1FET47W (1.21 ) 11/28/2016 RIP: 0010: (null) Code: Bad RIP value. RSP: 0018:ffff88036abcf740 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88036f5f6800 RCX: 1ffff1006debed26 RDX: ffff88036abcf920 RSI: ffff8803cb1a4f00 RDI: ffff8803c258c280 RBP: ffff8803c258c280 R08: ffff8803c258c280 R09: ffffed006f559d48 R10: ffff88037aacea43 R11: ffffed006f559d49 R12: ffff8803c258c280 R13: ffff8803cb1a4f20 R14: 00000000000000db R15: ffffffffc168a350 FS: 00007f7e631f4700(0000) GS:ffff8803d1c80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000003ccf64005 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? tls_sw_poll+0xa4/0x160 [tls] ? sock_poll+0x20a/0x680 ? do_select+0x77b/0x11a0 ? poll_schedule_timeout.constprop.12+0x130/0x130 ? pick_link+0xb00/0xb00 ? read_word_at_a_time+0x13/0x20 ? vfs_poll+0x270/0x270 ? deref_stack_reg+0xad/0xe0 ? __read_once_size_nocheck.constprop.6+0x10/0x10 [...] Debugging further, it turns out that calling into ctx->sk_poll() is invalid since sk_poll itself is NULL which was saved from the original TCP socket in order for tls_sw_poll() to invoke it. Looks like the recent conversion from poll to poll_mask callback started in 1525242310 ("net: add support for ->poll_mask in proto_ops") missed to eventually convert kTLS, too: TCP's ->poll was converted over to the ->poll_mask in commit 2c7d3daceb ("net/tcp: convert to ->poll_mask") and therefore kTLS wrongly saved the ->poll old one which is now NULL. Convert kTLS over to use ->poll_mask instead. Also instead of POLLIN | POLLRDNORM use the proper EPOLLIN | EPOLLRDNORM bits as the case in tcp_poll_mask() as well that is mangled here. Fixes: 2c7d3daceb ("net/tcp: convert to ->poll_mask") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Watson <davejwatson@fb.com> Tested-by: Dave Watson <davejwatson@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2018-06-11 16:29:54 -07:00
..
acpi	* Stratix10 SDRAM support to altera_edac (Thor Thayer)	2018-06-06 15:36:13 -07:00
asm-generic	int-ll64.h: define u{8,16,32,64} and s{8,16,32,64} based on uapi header	2018-06-07 17:34:38 -07:00
clocksource
crypto	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2018-06-05 15:51:21 -07:00
drm	drm for v4.18-rc1	2018-06-06 08:16:33 -07:00
dt-bindings	This time we have a good set of changes to the core framework that do some	2018-06-09 12:06:24 -07:00
keys
kvm
linux	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf	2018-06-11 14:24:32 -07:00
math-emu
media	media: v4l2-core: push taking ioctl mutex down to ioctl handler	2018-05-28 16:31:44 -04:00
memory
misc	ocxl: Expose the thread_id needed for wait on POWER9	2018-06-03 20:40:32 +10:00
net	tls: fix NULL pointer dereference on poll	2018-06-11 16:29:54 -07:00
pcmcia
ras
rdma	RDMA/restrack: Change SPDX tag to properly reflect license	2018-06-05 14:04:20 -06:00
scsi	SCSI misc on 20180610	2018-06-10 13:01:12 -07:00
soc
sound	sound updates for 4.18	2018-06-06 09:08:38 -07:00
target
trace	Merge branch 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2018-06-10 10:17:09 -07:00
uapi	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf	2018-06-11 14:24:32 -07:00
video
xen