The function xdp_convert_buff_to_frame() may return NULL if it fails
to correctly convert the XDP buffer into an XDP frame due to memory
constraints, internal errors, or invalid data. Failing to check for NULL
may lead to a NULL pointer dereference if the result is used later in
processing, potentially causing crashes, data corruption, or undefined
behavior.
On XDP redirect failure, the associated page must be released explicitly
if it was previously retained via get_page(). Failing to do so may result
in a memory leak, as the pages reference count is not decremented.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Cc: stable(a)vger.kernel.org # v5.9+
Fixes: 6c5aa6fc4def ("xen networking: add basic XDP support for xen-netfront")
Signed-off-by: Alexey Nepomnyashih <sdl(a)nppct.ru>
---
drivers/net/xen-netfront.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 63fe51d0e64d..1d3ff57a6125 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -985,20 +985,27 @@ static u32 xennet_run_xdp(struct netfront_queue *queue, struct page *pdata,
act = bpf_prog_run_xdp(prog, xdp);
switch (act) {
case XDP_TX:
- get_page(pdata);
xdpf = xdp_convert_buff_to_frame(xdp);
- err = xennet_xdp_xmit(queue->info->netdev, 1, &xdpf, 0);
- if (unlikely(!err))
- xdp_return_frame_rx_napi(xdpf);
- else if (unlikely(err < 0))
+ if (unlikely(!xdpf)) {
trace_xdp_exception(queue->info->netdev, prog, act);
+ break;
+ }
+ get_page(pdata);
+ err = xennet_xdp_xmit(queue->info->netdev, 1, &xdpf, 0);
+ if (unlikely(err <= 0)) {
+ if (err < 0)
+ trace_xdp_exception(queue->info->netdev, prog, act);
+ xdp_return_frame_rx_napi(xdpf);
+ }
break;
case XDP_REDIRECT:
get_page(pdata);
err = xdp_do_redirect(queue->info->netdev, xdp, prog);
*need_xdp_flush = true;
- if (unlikely(err))
+ if (unlikely(err)) {
trace_xdp_exception(queue->info->netdev, prog, act);
+ xdp_return_buff(xdp);
+ }
break;
case XDP_PASS:
case XDP_DROP:
--
2.43.0
arch_bpf_trampoline_size() provides JIT size of the BPF trampoline
before the buffer for JIT'ing it is allocated. The total number of
instructions emitted for BPF trampoline JIT code depends on where
the final image is located. So, the size arrived at with the dummy
pass in arch_bpf_trampoline_size() can vary from the actual size
needed in arch_prepare_bpf_trampoline(). When the instructions
accounted in arch_bpf_trampoline_size() is less than the number of
instructions emitted during the actual JIT compile of the trampoline,
the below warning is produced:
WARNING: CPU: 8 PID: 204190 at arch/powerpc/net/bpf_jit_comp.c:981 __arch_prepare_bpf_trampoline.isra.0+0xd2c/0xdcc
which is:
/* Make sure the trampoline generation logic doesn't overflow */
if (image && WARN_ON_ONCE(&image[ctx->idx] >
(u32 *)rw_image_end - BPF_INSN_SAFETY)) {
So, during the dummy pass, instead of providing some arbitrary image
location, account for maximum possible instructions if and when there
is a dependency with image location for JIT'ing.
Fixes: d243b62b7bd3 ("powerpc64/bpf: Add support for bpf trampolines")
Reported-by: Venkat Rao Bagalkote <venkat88(a)linux.ibm.com>
Closes: https://lore.kernel.org/all/6168bfc8-659f-4b5a-a6fb-90a916dde3b3@linux.ibm.…
Cc: stable(a)vger.kernel.org # v6.13+
Signed-off-by: Hari Bathini <hbathini(a)linux.ibm.com>
---
Changes since v1:
- Pass NULL for image during intial pass and account for max. possible
instruction during this pass as Naveen suggested.
arch/powerpc/net/bpf_jit.h | 20 ++++++++++++++++---
arch/powerpc/net/bpf_jit_comp.c | 33 ++++++++++---------------------
arch/powerpc/net/bpf_jit_comp64.c | 9 +++++++++
3 files changed, 36 insertions(+), 26 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 6beacaec63d3..4c26912c2e3c 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -51,8 +51,16 @@
EMIT(PPC_INST_BRANCH_COND | (((cond) & 0x3ff) << 16) | (offset & 0xfffc)); \
} while (0)
-/* Sign-extended 32-bit immediate load */
+/*
+ * Sign-extended 32-bit immediate load
+ *
+ * If this is a dummy pass (!image), account for
+ * maximum possible instructions.
+ */
#define PPC_LI32(d, i) do { \
+ if (!image) \
+ ctx->idx += 2; \
+ else { \
if ((int)(uintptr_t)(i) >= -32768 && \
(int)(uintptr_t)(i) < 32768) \
EMIT(PPC_RAW_LI(d, i)); \
@@ -60,10 +68,15 @@
EMIT(PPC_RAW_LIS(d, IMM_H(i))); \
if (IMM_L(i)) \
EMIT(PPC_RAW_ORI(d, d, IMM_L(i))); \
- } } while(0)
+ } \
+ } } while (0)
#ifdef CONFIG_PPC64
+/* If dummy pass (!image), account for maximum possible instructions */
#define PPC_LI64(d, i) do { \
+ if (!image) \
+ ctx->idx += 5; \
+ else { \
if ((long)(i) >= -2147483648 && \
(long)(i) < 2147483648) \
PPC_LI32(d, i); \
@@ -84,7 +97,8 @@
if ((uintptr_t)(i) & 0x000000000000ffffULL) \
EMIT(PPC_RAW_ORI(d, d, (uintptr_t)(i) & \
0xffff)); \
- } } while (0)
+ } \
+ } } while (0)
#define PPC_LI_ADDR PPC_LI64
#ifndef CONFIG_PPC_KERNEL_PCREL
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 2991bb171a9b..c0684733e9d6 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -504,10 +504,11 @@ static int invoke_bpf_prog(u32 *image, u32 *ro_image, struct codegen_context *ct
EMIT(PPC_RAW_ADDI(_R3, _R1, regs_off));
if (!p->jited)
PPC_LI_ADDR(_R4, (unsigned long)p->insnsi);
- if (!create_branch(&branch_insn, (u32 *)&ro_image[ctx->idx], (unsigned long)p->bpf_func,
- BRANCH_SET_LINK)) {
- if (image)
- image[ctx->idx] = ppc_inst_val(branch_insn);
+ /* Account for max possible instructions during dummy pass for size calculation */
+ if (image && !create_branch(&branch_insn, (u32 *)&ro_image[ctx->idx],
+ (unsigned long)p->bpf_func,
+ BRANCH_SET_LINK)) {
+ image[ctx->idx] = ppc_inst_val(branch_insn);
ctx->idx++;
} else {
EMIT(PPC_RAW_LL(_R12, _R25, offsetof(struct bpf_prog, bpf_func)));
@@ -889,7 +890,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
bpf_trampoline_restore_tail_call_cnt(image, ctx, func_frame_offset, r4_off);
/* Reserve space to patch branch instruction to skip fexit progs */
- im->ip_after_call = &((u32 *)ro_image)[ctx->idx];
+ if (ro_image) /* image is NULL for dummy pass */
+ im->ip_after_call = &((u32 *)ro_image)[ctx->idx];
EMIT(PPC_RAW_NOP());
}
@@ -912,7 +914,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
}
if (flags & BPF_TRAMP_F_CALL_ORIG) {
- im->ip_epilogue = &((u32 *)ro_image)[ctx->idx];
+ if (ro_image) /* image is NULL for dummy pass */
+ im->ip_epilogue = &((u32 *)ro_image)[ctx->idx];
PPC_LI_ADDR(_R3, im);
ret = bpf_jit_emit_func_call_rel(image, ro_image, ctx,
(unsigned long)__bpf_tramp_exit);
@@ -973,25 +976,9 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
struct bpf_tramp_links *tlinks, void *func_addr)
{
struct bpf_tramp_image im;
- void *image;
int ret;
- /*
- * Allocate a temporary buffer for __arch_prepare_bpf_trampoline().
- * This will NOT cause fragmentation in direct map, as we do not
- * call set_memory_*() on this buffer.
- *
- * We cannot use kvmalloc here, because we need image to be in
- * module memory range.
- */
- image = bpf_jit_alloc_exec(PAGE_SIZE);
- if (!image)
- return -ENOMEM;
-
- ret = __arch_prepare_bpf_trampoline(&im, image, image + PAGE_SIZE, image,
- m, flags, tlinks, func_addr);
- bpf_jit_free_exec(image);
-
+ ret = __arch_prepare_bpf_trampoline(&im, NULL, NULL, NULL, m, flags, tlinks, func_addr);
return ret;
}
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index 233703b06d7c..91f9efe8b8d7 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -225,6 +225,15 @@ int bpf_jit_emit_func_call_rel(u32 *image, u32 *fimage, struct codegen_context *
}
#ifdef CONFIG_PPC_KERNEL_PCREL
+ /*
+ * If fimage is NULL (the initial pass to find image size),
+ * account for the maximum no. of instructions possible.
+ */
+ if (!fimage) {
+ ctx->idx += 7;
+ return 0;
+ }
+
reladdr = func_addr - local_paca->kernelbase;
if (reladdr < (long)SZ_8G && reladdr >= -(long)SZ_8G) {
--
2.49.0
The backport of upstream commit c8070b787519 ("mm: Don't pin ZERO_PAGE
in pin_user_pages()") into v6.1.130 noted below in Fixes does not
account for commit 0f0892356fa1 ("mm: allow multiple error returns in
try_grab_page()"), which changed the return value of try_grab_page()
from bool to int. Therefore returning 0, success in the upstream
version, becomes an error here. Fix the return value.
Fixes: 476c1dfefab8 ("mm: Don't pin ZERO_PAGE in pin_user_pages()")
Link: https://lore.kernel.org/all/Z_6uhLQjJ7SSzI13@eldamar.lan
Reported-by: Salvatore Bonaccorso <carnil(a)debian.org>
Reported-by: Milan Broz <gmazyland(a)gmail.com>
Cc: stable(a)vger.kernel.org
Cc: linux-kernel(a)vger.kernel.org
Cc: linux-mm(a)kvack.org
Cc: Sasha Levin <sashal(a)kernel.org>
Signed-off-by: Alex Williamson <alex.williamson(a)redhat.com>
---
mm/gup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/gup.c b/mm/gup.c
index b1daaa9d89aa..76a2b0943e2d 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -232,7 +232,7 @@ bool __must_check try_grab_page(struct page *page, unsigned int flags)
* and it is used in a *lot* of places.
*/
if (is_zero_page(page))
- return 0;
+ return true;
/*
* Similar to try_grab_folio(): be sure to *also*
--
2.48.1
From: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
commit a8972d5a49b4 ("drm: panel: jd9365da-h3: fix reset signal polarity")
fixed reset signal polarity in jadard_dsi_probe() and jadard_prepare().
It was not done in jadard_unprepare() because of an incorrect assumption
about reset line handling in power off mode. After looking into the
datasheet, it now appears that before disabling regulators, the reset line
is deasserted first, and if reset_before_power_off_vcioo is true, then the
reset line is asserted.
Fix reset polarity by inverting gpiod_set_value() second argument in
in jadard_unprepare().
Fixes: 6b818c533dd8 ("drm: panel: Add Jadard JD9365DA-H3 DSI panel")
Fixes: 2b976ad760dc ("drm/panel: jd9365da: Support for kd101ne3-40ti MIPI-DSI panel")
Fixes: a8972d5a49b4 ("drm: panel: jd9365da-h3: fix reset signal polarity")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve(a)dimonoff.com>
---
drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c b/drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c
index 7d68a8acfe2ea..eb0f8373258c3 100644
--- a/drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c
+++ b/drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c
@@ -129,11 +129,11 @@ static int jadard_unprepare(struct drm_panel *panel)
{
struct jadard *jadard = panel_to_jadard(panel);
- gpiod_set_value(jadard->reset, 1);
+ gpiod_set_value(jadard->reset, 0);
msleep(120);
if (jadard->desc->reset_before_power_off_vcioo) {
- gpiod_set_value(jadard->reset, 0);
+ gpiod_set_value(jadard->reset, 1);
usleep_range(1000, 2000);
}
base-commit: 7adf8b1afc14832de099f9e178f08f91dc0dd6d0
--
2.39.5