4.9-stable patches

added patches:
	alsa-emu8000-fix-a-use-after-free-in-snd_emu8000_create_mixer.patch
	alsa-sb-fix-two-use-after-free-in-snd_sb_qsound_build.patch

diff --git a/queue-4.9/alsa-emu8000-fix-a-use-after-free-in-snd_emu8000_create_mixer.patch b/queue-4.9/alsa-emu8000-fix-a-use-after-free-in-snd_emu8000_create_mixer.patch
new file mode 100644 (file)
index 0000000..c455f2d
--- /dev/null
+++ b/queue-4.9/alsa-emu8000-fix-a-use-after-free-in-snd_emu8000_create_mixer.patch
@@ -0,0 +1,44 @@
+From 1c98f574403dbcf2eb832d5535a10d967333ef2d Mon Sep 17 00:00:00 2001
+From: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
+Date: Mon, 26 Apr 2021 06:11:29 -0700
+Subject: ALSA: emu8000: Fix a use after free in snd_emu8000_create_mixer
+
+From: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
+
+commit 1c98f574403dbcf2eb832d5535a10d967333ef2d upstream.
+
+Our code analyzer reported a uaf.
+
+In snd_emu8000_create_mixer, the callee snd_ctl_add(..,emu->controls[i])
+calls snd_ctl_add_replace(.., kcontrol,..). Inside snd_ctl_add_replace(),
+if error happens, kcontrol will be freed by snd_ctl_free_one(kcontrol).
+Then emu->controls[i] points to a freed memory, and the execution comes
+to __error branch of snd_emu8000_create_mixer. The freed emu->controls[i]
+is used in snd_ctl_remove(card, emu->controls[i]).
+
+My patch set emu->controls[i] to NULL if snd_ctl_add() failed to avoid
+the uaf.
+
+Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
+Cc: <stable@vger.kernel.org>
+Link: https://lore.kernel.org/r/20210426131129.4796-1-lyl2019@mail.ustc.edu.cn
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ sound/isa/sb/emu8000.c |    4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/sound/isa/sb/emu8000.c
++++ b/sound/isa/sb/emu8000.c
+@@ -1042,8 +1042,10 @@ snd_emu8000_create_mixer(struct snd_card
+ 
+       memset(emu->controls, 0, sizeof(emu->controls));
+       for (i = 0; i < EMU8000_NUM_CONTROLS; i++) {
+-              if ((err = snd_ctl_add(card, emu->controls[i] = snd_ctl_new1(mixer_defs[i], emu))) < 0)
++              if ((err = snd_ctl_add(card, emu->controls[i] = snd_ctl_new1(mixer_defs[i], emu))) < 0) {
++                      emu->controls[i] = NULL;
+                       goto __error;
++              }
+       }
+       return 0;
+ 

diff --git a/queue-4.9/alsa-sb-fix-two-use-after-free-in-snd_sb_qsound_build.patch b/queue-4.9/alsa-sb-fix-two-use-after-free-in-snd_sb_qsound_build.patch
new file mode 100644 (file)
index 0000000..20bae7b
--- /dev/null
+++ b/queue-4.9/alsa-sb-fix-two-use-after-free-in-snd_sb_qsound_build.patch
@@ -0,0 +1,50 @@
+From 4fb44dd2c1dda18606348acdfdb97e8759dde9df Mon Sep 17 00:00:00 2001
+From: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
+Date: Mon, 26 Apr 2021 07:55:41 -0700
+Subject: ALSA: sb: Fix two use after free in snd_sb_qsound_build
+
+From: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
+
+commit 4fb44dd2c1dda18606348acdfdb97e8759dde9df upstream.
+
+In snd_sb_qsound_build, snd_ctl_add(..,p->qsound_switch...) and
+snd_ctl_add(..,p->qsound_space..) are called. But the second
+arguments of snd_ctl_add() could be freed via snd_ctl_add_replace()
+->snd_ctl_free_one(). After the error code is returned,
+snd_sb_qsound_destroy(p) is called in __error branch.
+
+But in snd_sb_qsound_destroy(), the freed p->qsound_switch and
+p->qsound_space are still used by snd_ctl_remove().
+
+My patch set p->qsound_switch and p->qsound_space to NULL if
+snd_ctl_add() failed to avoid the uaf bugs. But these codes need
+to further be improved with the code style.
+
+Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
+Cc: <stable@vger.kernel.org>
+Link: https://lore.kernel.org/r/20210426145541.8070-1-lyl2019@mail.ustc.edu.cn
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ sound/isa/sb/sb16_csp.c |    8 ++++++--
+ 1 file changed, 6 insertions(+), 2 deletions(-)
+
+--- a/sound/isa/sb/sb16_csp.c
++++ b/sound/isa/sb/sb16_csp.c
+@@ -1059,10 +1059,14 @@ static int snd_sb_qsound_build(struct sn
+ 
+       spin_lock_init(&p->q_lock);
+ 
+-      if ((err = snd_ctl_add(card, p->qsound_switch = snd_ctl_new1(&snd_sb_qsound_switch, p))) < 0)
++      if ((err = snd_ctl_add(card, p->qsound_switch = snd_ctl_new1(&snd_sb_qsound_switch, p))) < 0) {
++              p->qsound_switch = NULL;
+               goto __error;
+-      if ((err = snd_ctl_add(card, p->qsound_space = snd_ctl_new1(&snd_sb_qsound_space, p))) < 0)
++      }
++      if ((err = snd_ctl_add(card, p->qsound_space = snd_ctl_new1(&snd_sb_qsound_space, p))) < 0) {
++              p->qsound_space = NULL;
+               goto __error;
++      }
+ 
+       return 0;
+ 

diff --git a/queue-4.9/series b/queue-4.9/series
index 6b39019b60cb74d33c8c5e651762c76f3361d658..7b86a3f677f07253ae591caae104171e1ae22c45 100644 (file)
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -45,3 +45,5 @@ drm-msm-mdp5-configure-pp_sync_height-to-double-the-.patch
 drm-amdgpu-fix-null-pointer-dereference.patch
 scsi-lpfc-fix-crash-when-a-reg_rpi-mailbox-fails-tri.patch
 scsi-libfc-fix-a-format-specifier.patch
+alsa-emu8000-fix-a-use-after-free-in-snd_emu8000_create_mixer.patch
+alsa-sb-fix-two-use-after-free-in-snd_sb_qsound_build.patch