From: Hawkins Jiawei yin31149@gmail.com
[ Upstream commit 26215b7ee923b9251f7bb12c4e5f09dc465d35f2 ]
Syzkaller reports a null-ptr-deref bug as follows: ====================================================== KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380 [...] Call Trace: <TASK> vfs_parse_fs_param fs/fs_context.c:148 [inline] vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129 vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191 generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231 do_new_mount fs/namespace.c:3036 [inline] path_mount+0x12de/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] </TASK> ======================================================
According to commit "vfs: parse: deal with zero length string value", kernel will set the param->string to null pointer in vfs_parse_fs_string() if fs string has zero length.
Yet the problem is that, hugetlbfs_parse_param() will dereference the param->string, without checking whether it is a null pointer. To be more specific, if hugetlbfs_parse_param() parses an illegal mount parameter, such as "size=,", kernel will constructs struct fs_parameter with null pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.
This patch solves it by adding sanity check on param->string in hugetlbfs_parse_param().
Link: https://lkml.kernel.org/r/20221020231609.4810-1-yin31149@gmail.com Reported-by: syzbot+a3e6acd85ded5c16a709@syzkaller.appspotmail.com Tested-by: syzbot+a3e6acd85ded5c16a709@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/0000000000005ad00405eb7148c6@google.com/ Signed-off-by: Hawkins Jiawei yin31149@gmail.com Reviewed-by: Mike Kravetz mike.kravetz@oracle.com Cc: Hawkins Jiawei yin31149@gmail.com Cc: Muchun Song songmuchun@bytedance.com Cc: Ian Kent raven@themaw.net Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/hugetlbfs/inode.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index a2f43f1a85f8..5181e6d4e18c 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -1261,7 +1261,7 @@ static int hugetlbfs_parse_param(struct fs_context *fc, struct fs_parameter *par
case Opt_size: /* memparse() will accept a K/M/G without a digit */ - if (!isdigit(param->string[0])) + if (!param->string || !isdigit(param->string[0])) goto bad_val; ctx->max_size_opt = memparse(param->string, &rest); ctx->max_val_type = SIZE_STD; @@ -1271,7 +1271,7 @@ static int hugetlbfs_parse_param(struct fs_context *fc, struct fs_parameter *par
case Opt_nr_inodes: /* memparse() will accept a K/M/G without a digit */ - if (!isdigit(param->string[0])) + if (!param->string || !isdigit(param->string[0])) goto bad_val; ctx->nr_inodes = memparse(param->string, &rest); return 0; @@ -1287,7 +1287,7 @@ static int hugetlbfs_parse_param(struct fs_context *fc, struct fs_parameter *par
case Opt_min_size: /* memparse() will accept a K/M/G without a digit */ - if (!isdigit(param->string[0])) + if (!param->string || !isdigit(param->string[0])) goto bad_val; ctx->min_size_opt = memparse(param->string, &rest); ctx->min_val_type = SIZE_STD;
From: Nathan Chancellor nathan@kernel.org
[ Upstream commit 96d845a67b7e406cfed7880a724c8ca6121e022e ]
With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), indirect call targets are validated against the expected function pointer prototype to make sure the call target is valid to help mitigate ROP attacks. If they are not identical, there is a failure at run time, which manifests as either a kernel panic or thread getting killed. A proposed warning in clang aims to catch these at compile time, which reveals:
drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c:74:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict] .mode_valid = fsl_dcu_drm_connector_mode_valid, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 error generated.
->mode_valid() in 'struct drm_connector_helper_funcs' expects a return type of 'enum drm_mode_status', not 'int'. Adjust the return type of fsl_dcu_drm_connector_mode_valid() to match the prototype's to resolve the warning and CFI failure.
Link: https://github.com/ClangBuiltLinux/linux/issues/1750 Reported-by: Sami Tolvanen samitolvanen@google.com Signed-off-by: Nathan Chancellor nathan@kernel.org Reviewed-by: Kees Cook keescook@chromium.org Signed-off-by: Kees Cook keescook@chromium.org Link: https://lore.kernel.org/r/20221102154215.78059-1-nathan@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c index 4d4a715b429d..2c2b92324a2e 100644 --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c @@ -60,8 +60,9 @@ static int fsl_dcu_drm_connector_get_modes(struct drm_connector *connector) return drm_panel_get_modes(fsl_connector->panel, connector); }
-static int fsl_dcu_drm_connector_mode_valid(struct drm_connector *connector, - struct drm_display_mode *mode) +static enum drm_mode_status +fsl_dcu_drm_connector_mode_valid(struct drm_connector *connector, + struct drm_display_mode *mode) { if (mode->hdisplay & 0xf) return MODE_ERROR;
From: Nathan Chancellor nathan@kernel.org
[ Upstream commit 0ad811cc08a937d875cbad0149c1bab17f84ba05 ]
With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), indirect call targets are validated against the expected function pointer prototype to make sure the call target is valid to help mitigate ROP attacks. If they are not identical, there is a failure at run time, which manifests as either a kernel panic or thread getting killed. A proposed warning in clang aims to catch these at compile time, which reveals:
drivers/gpu/drm/sti/sti_hda.c:637:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict] .mode_valid = sti_hda_connector_mode_valid, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/sti/sti_dvo.c:376:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict] .mode_valid = sti_dvo_connector_mode_valid, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/sti/sti_hdmi.c:1035:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict] .mode_valid = sti_hdmi_connector_mode_valid, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
->mode_valid() in 'struct drm_connector_helper_funcs' expects a return type of 'enum drm_mode_status', not 'int'. Adjust the return type of sti_{dvo,hda,hdmi}_connector_mode_valid() to match the prototype's to resolve the warning and CFI failure.
Link: https://github.com/ClangBuiltLinux/linux/issues/1750 Signed-off-by: Nathan Chancellor nathan@kernel.org Reviewed-by: Kees Cook keescook@chromium.org Signed-off-by: Kees Cook keescook@chromium.org Link: https://lore.kernel.org/r/20221102155623.3042869-1-nathan@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/sti/sti_dvo.c | 5 +++-- drivers/gpu/drm/sti/sti_hda.c | 5 +++-- drivers/gpu/drm/sti/sti_hdmi.c | 5 +++-- 3 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/sti/sti_dvo.c b/drivers/gpu/drm/sti/sti_dvo.c index ddb4184f0726..58b092eb8907 100644 --- a/drivers/gpu/drm/sti/sti_dvo.c +++ b/drivers/gpu/drm/sti/sti_dvo.c @@ -346,8 +346,9 @@ static int sti_dvo_connector_get_modes(struct drm_connector *connector)
#define CLK_TOLERANCE_HZ 50
-static int sti_dvo_connector_mode_valid(struct drm_connector *connector, - struct drm_display_mode *mode) +static enum drm_mode_status +sti_dvo_connector_mode_valid(struct drm_connector *connector, + struct drm_display_mode *mode) { int target = mode->clock * 1000; int target_min = target - CLK_TOLERANCE_HZ; diff --git a/drivers/gpu/drm/sti/sti_hda.c b/drivers/gpu/drm/sti/sti_hda.c index 5c2b650b561d..bc04b8f50b09 100644 --- a/drivers/gpu/drm/sti/sti_hda.c +++ b/drivers/gpu/drm/sti/sti_hda.c @@ -600,8 +600,9 @@ static int sti_hda_connector_get_modes(struct drm_connector *connector)
#define CLK_TOLERANCE_HZ 50
-static int sti_hda_connector_mode_valid(struct drm_connector *connector, - struct drm_display_mode *mode) +static enum drm_mode_status +sti_hda_connector_mode_valid(struct drm_connector *connector, + struct drm_display_mode *mode) { int target = mode->clock * 1000; int target_min = target - CLK_TOLERANCE_HZ; diff --git a/drivers/gpu/drm/sti/sti_hdmi.c b/drivers/gpu/drm/sti/sti_hdmi.c index 38a558768e53..b0890234ffbe 100644 --- a/drivers/gpu/drm/sti/sti_hdmi.c +++ b/drivers/gpu/drm/sti/sti_hdmi.c @@ -997,8 +997,9 @@ static int sti_hdmi_connector_get_modes(struct drm_connector *connector)
#define CLK_TOLERANCE_HZ 50
-static int sti_hdmi_connector_mode_valid(struct drm_connector *connector, - struct drm_display_mode *mode) +static enum drm_mode_status +sti_hdmi_connector_mode_valid(struct drm_connector *connector, + struct drm_display_mode *mode) { int target = mode->clock * 1000; int target_min = target - CLK_TOLERANCE_HZ;
From: Zhang Xiaoxu zhangxiaoxu5@huawei.com
[ Upstream commit d23417a5bf3a3afc55de5442eb46e1e60458b0a1 ]
When insert and remove the orangefs module, then debug_help_string will be leaked:
unreferenced object 0xffff8881652ba000 (size 4096): comm "insmod", pid 1701, jiffies 4294893639 (age 13218.530s) hex dump (first 32 bytes): 43 6c 69 65 6e 74 20 44 65 62 75 67 20 4b 65 79 Client Debug Key 77 6f 72 64 73 20 61 72 65 20 75 6e 6b 6e 6f 77 words are unknow backtrace: [<0000000004e6f8e3>] kmalloc_trace+0x27/0xa0 [<0000000006f75d85>] orangefs_prepare_debugfs_help_string+0x5e/0x480 [orangefs] [<0000000091270a2a>] _sub_I_65535_1+0x57/0xf70 [crc_itu_t] [<000000004b1ee1a3>] do_one_initcall+0x87/0x2a0 [<000000001d0614ae>] do_init_module+0xdf/0x320 [<00000000efef068c>] load_module+0x2f98/0x3330 [<000000006533b44d>] __do_sys_finit_module+0x113/0x1b0 [<00000000a0da6f99>] do_syscall_64+0x35/0x80 [<000000007790b19b>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
When remove the module, should always free debug_help_string. Should always free the allocated buffer when change the free_debug_help_string.
Signed-off-by: Zhang Xiaoxu zhangxiaoxu5@huawei.com Signed-off-by: Mike Marshall hubcap@omnibond.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/orangefs/orangefs-debugfs.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c index 29eaa4544372..a848b6ef9599 100644 --- a/fs/orangefs/orangefs-debugfs.c +++ b/fs/orangefs/orangefs-debugfs.c @@ -222,6 +222,8 @@ static void orangefs_kernel_debug_init(void) void orangefs_debugfs_cleanup(void) { debugfs_remove_recursive(debug_dir); + kfree(debug_help_string); + debug_help_string = NULL; }
/* open ORANGEFS_KMOD_DEBUG_HELP_FILE */ @@ -671,6 +673,7 @@ int orangefs_prepare_debugfs_help_string(int at_boot) memset(debug_help_string, 0, DEBUG_HELP_STRING_SIZE); strlcat(debug_help_string, new, string_size); mutex_unlock(&orangefs_help_file_lock); + kfree(new); }
rc = 0;
From: Zhang Xiaoxu zhangxiaoxu5@huawei.com
[ Upstream commit 31720a2b109b3080eb77e97b8f6f50a27b4ae599 ]
When insert and remove the orangefs module, there are memory leaked as below:
unreferenced object 0xffff88816b0cc000 (size 2048): comm "insmod", pid 783, jiffies 4294813439 (age 65.512s) hex dump (first 32 bytes): 6e 6f 6e 65 0a 00 00 00 00 00 00 00 00 00 00 00 none............ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000031ab7788>] kmalloc_trace+0x27/0xa0 [<000000005b405fee>] orangefs_debugfs_init.cold+0xaf/0x17f [<00000000e5a0085b>] 0xffffffffa02780f9 [<000000004232d9f7>] do_one_initcall+0x87/0x2a0 [<0000000054f22384>] do_init_module+0xdf/0x320 [<000000003263bdea>] load_module+0x2f98/0x3330 [<0000000052cd4153>] __do_sys_finit_module+0x113/0x1b0 [<00000000250ae02b>] do_syscall_64+0x35/0x80 [<00000000f11c03c7>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
Use the golbal variable as the buffer rather than dynamic allocate to slove the problem.
Signed-off-by: Zhang Xiaoxu zhangxiaoxu5@huawei.com Signed-off-by: Mike Marshall hubcap@omnibond.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/orangefs/orangefs-debugfs.c | 26 +++----------------------- 1 file changed, 3 insertions(+), 23 deletions(-)
diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c index a848b6ef9599..1b508f543384 100644 --- a/fs/orangefs/orangefs-debugfs.c +++ b/fs/orangefs/orangefs-debugfs.c @@ -194,15 +194,10 @@ void orangefs_debugfs_init(int debug_mask) */ static void orangefs_kernel_debug_init(void) { - int rc = -ENOMEM; - char *k_buffer = NULL; + static char k_buffer[ORANGEFS_MAX_DEBUG_STRING_LEN] = { };
gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: start\n", __func__);
- k_buffer = kzalloc(ORANGEFS_MAX_DEBUG_STRING_LEN, GFP_KERNEL); - if (!k_buffer) - goto out; - if (strlen(kernel_debug_string) + 1 < ORANGEFS_MAX_DEBUG_STRING_LEN) { strcpy(k_buffer, kernel_debug_string); strcat(k_buffer, "\n"); @@ -213,9 +208,6 @@ static void orangefs_kernel_debug_init(void)
debugfs_create_file(ORANGEFS_KMOD_DEBUG_FILE, 0444, debug_dir, k_buffer, &kernel_debug_fops); - -out: - gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: rc:%d:\n", __func__, rc); }
@@ -299,18 +291,13 @@ static int help_show(struct seq_file *m, void *v) /* * initialize the client-debug file. */ -static int orangefs_client_debug_init(void) +static void orangefs_client_debug_init(void) {
- int rc = -ENOMEM; - char *c_buffer = NULL; + static char c_buffer[ORANGEFS_MAX_DEBUG_STRING_LEN] = { };
gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: start\n", __func__);
- c_buffer = kzalloc(ORANGEFS_MAX_DEBUG_STRING_LEN, GFP_KERNEL); - if (!c_buffer) - goto out; - if (strlen(client_debug_string) + 1 < ORANGEFS_MAX_DEBUG_STRING_LEN) { strcpy(c_buffer, client_debug_string); strcat(c_buffer, "\n"); @@ -324,13 +311,6 @@ static int orangefs_client_debug_init(void) debug_dir, c_buffer, &kernel_debug_fops); - - rc = 0; - -out: - - gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: rc:%d:\n", __func__, rc); - return rc; }
/* open ORANGEFS_KMOD_DEBUG_FILE or ORANGEFS_CLIENT_DEBUG_FILE.*/
linux-stable-mirror@lists.linaro.org
-
Sasha Levin