October 2023 - Linux-stable-mirror

FAILED: patch "[PATCH] x86/i8259: Skip probing when ACPI/MADT advertises PCAT" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 128b0c9781c9f2651bea163cb85e52a6c7be0f9e # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023102936-encounter-impatient-894d@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 128b0c9781c9f2651bea163cb85e52a6c7be0f9e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner <tglx(a)linutronix.de> Date: Wed, 25 Oct 2023 23:04:15 +0200 Subject: [PATCH] x86/i8259: Skip probing when ACPI/MADT advertises PCAT compatibility David and a few others reported that on certain newer systems some legacy interrupts fail to work correctly. Debugging revealed that the BIOS of these systems leaves the legacy PIC in uninitialized state which makes the PIC detection fail and the kernel switches to a dummy implementation. Unfortunately this fallback causes quite some code to fail as it depends on checks for the number of legacy PIC interrupts or the availability of the real PIC. In theory there is no reason to use the PIC on any modern system when IO/APIC is available, but the dependencies on the related checks cannot be resolved trivially and on short notice. This needs lots of analysis and rework. The PIC detection has been added to avoid quirky checks and force selection of the dummy implementation all over the place, especially in VM guest scenarios. So it's not an option to revert the relevant commit as that would break a lot of other scenarios. One solution would be to try to initialize the PIC on detection fail and retry the detection, but that puts the burden on everything which does not have a PIC. Fortunately the ACPI/MADT table header has a flag field, which advertises in bit 0 that the system is PCAT compatible, which means it has a legacy 8259 PIC. Evaluate that bit and if set avoid the detection routine and keep the real PIC installed, which then gets initialized (for nothing) and makes the rest of the code with all the dependencies work again. Fixes: e179f6914152 ("x86, irq, pic: Probe for legacy PIC and set legacy_pic appropriately") Reported-by: David Lazar <dlazar(a)gmail.com> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Tested-by: David Lazar <dlazar(a)gmail.com> Reviewed-by: Hans de Goede <hdegoede(a)redhat.com> Reviewed-by: Mario Limonciello <mario.limonciello(a)amd.com> Cc: stable(a)vger.kernel.org Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218003 Link: https://lore.kernel.org/r/875y2u5s8g.ffs@tglx diff --git a/arch/x86/include/asm/i8259.h b/arch/x86/include/asm/i8259.h index 637fa1df3512..c715097e92fd 100644 --- a/arch/x86/include/asm/i8259.h +++ b/arch/x86/include/asm/i8259.h @@ -69,6 +69,8 @@ struct legacy_pic { void (*make_irq)(unsigned int irq); }; +void legacy_pic_pcat_compat(void); + extern struct legacy_pic *legacy_pic; extern struct legacy_pic null_legacy_pic; diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 2a0ea38955df..c55c0ef47a18 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -148,6 +148,9 @@ static int __init acpi_parse_madt(struct acpi_table_header *table) pr_debug("Local APIC address 0x%08x\n", madt->address); } + if (madt->flags & ACPI_MADT_PCAT_COMPAT) + legacy_pic_pcat_compat(); + /* ACPI 6.3 and newer support the online capable bit. */ if (acpi_gbl_FADT.header.revision > 6 || (acpi_gbl_FADT.header.revision == 6 && diff --git a/arch/x86/kernel/i8259.c b/arch/x86/kernel/i8259.c index 30a55207c000..c20d1832c481 100644 --- a/arch/x86/kernel/i8259.c +++ b/arch/x86/kernel/i8259.c @@ -32,6 +32,7 @@ */ static void init_8259A(int auto_eoi); +static bool pcat_compat __ro_after_init; static int i8259A_auto_eoi; DEFINE_RAW_SPINLOCK(i8259A_lock); @@ -299,15 +300,32 @@ static void unmask_8259A(void) static int probe_8259A(void) { + unsigned char new_val, probe_val = ~(1 << PIC_CASCADE_IR); unsigned long flags; - unsigned char probe_val = ~(1 << PIC_CASCADE_IR); - unsigned char new_val; + + /* + * If MADT has the PCAT_COMPAT flag set, then do not bother probing + * for the PIC. Some BIOSes leave the PIC uninitialized and probing + * fails. + * + * Right now this causes problems as quite some code depends on + * nr_legacy_irqs() > 0 or has_legacy_pic() == true. This is silly + * when the system has an IO/APIC because then PIC is not required + * at all, except for really old machines where the timer interrupt + * must be routed through the PIC. So just pretend that the PIC is + * there and let legacy_pic->init() initialize it for nothing. + * + * Alternatively this could just try to initialize the PIC and + * repeat the probe, but for cases where there is no PIC that's + * just pointless. + */ + if (pcat_compat) + return nr_legacy_irqs(); + /* - * Check to see if we have a PIC. - * Mask all except the cascade and read - * back the value we just wrote. If we don't - * have a PIC, we will read 0xff as opposed to the - * value we wrote. + * Check to see if we have a PIC. Mask all except the cascade and + * read back the value we just wrote. If we don't have a PIC, we + * will read 0xff as opposed to the value we wrote. */ raw_spin_lock_irqsave(&i8259A_lock, flags); @@ -429,5 +447,9 @@ static int __init i8259A_init_ops(void) return 0; } - device_initcall(i8259A_init_ops); + +void __init legacy_pic_pcat_compat(void) +{ + pcat_compat = true; +}

1 year, 2 months

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[PATCH 6.5] accel/ivpu/37xx: Fix missing VPUIP interrupts

by Stanislaw Gruszka

From: Karol Wachowski <karol.wachowski(a)linux.intel.com> commit b132ac51d7a50c37683be56c96ff64f8c887930f upstream. Move sequence of masking and unmasking global interrupts from buttress interrupt handler to generic one that handles both VPUIP and BTRS interrupts. Unmasking global interrupts will re-trigger MSI for any pending interrupts. Lack of this sequence will cause the driver to miss any VPUIP interrupt that comes after reading VPU_37XX_HOST_SS_ICB_STATUS_0 and before clearing all active interrupt sources. Fixes: 35b137630f08 ("accel/ivpu: Introduce a new DRM driver for Intel VPU") Cc: stable(a)vger.kernel.org Signed-off-by: Karol Wachowski <karol.wachowski(a)linux.intel.com> Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka(a)linux.intel.com> Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka(a)linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231024161952.759914-1-stani… --- drivers/accel/ivpu/ivpu_hw_mtl.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/accel/ivpu/ivpu_hw_mtl.c b/drivers/accel/ivpu/ivpu_hw_mtl.c index 2a5dd3a5dc46..9a49255e60c8 100644 --- a/drivers/accel/ivpu/ivpu_hw_mtl.c +++ b/drivers/accel/ivpu/ivpu_hw_mtl.c @@ -953,9 +953,6 @@ static u32 ivpu_hw_mtl_irqb_handler(struct ivpu_device *vdev, int irq) if (status == 0) return 0; - /* Disable global interrupt before handling local buttress interrupts */ - REGB_WR32(MTL_BUTTRESS_GLOBAL_INT_MASK, 0x1); - if (REG_TEST_FLD(MTL_BUTTRESS_INTERRUPT_STAT, FREQ_CHANGE, status)) ivpu_dbg(vdev, IRQ, "FREQ_CHANGE irq: %08x", REGB_RD32(MTL_BUTTRESS_CURRENT_PLL)); @@ -986,9 +983,6 @@ static u32 ivpu_hw_mtl_irqb_handler(struct ivpu_device *vdev, int irq) else REGB_WR32(MTL_BUTTRESS_INTERRUPT_STAT, status); - /* Re-enable global interrupt */ - REGB_WR32(MTL_BUTTRESS_GLOBAL_INT_MASK, 0x0); - if (schedule_recovery) ivpu_pm_schedule_recovery(vdev); @@ -1000,9 +994,14 @@ static irqreturn_t ivpu_hw_mtl_irq_handler(int irq, void *ptr) struct ivpu_device *vdev = ptr; u32 ret_irqv, ret_irqb; + REGB_WR32(MTL_BUTTRESS_GLOBAL_INT_MASK, 0x1); + ret_irqv = ivpu_hw_mtl_irqv_handler(vdev, irq); ret_irqb = ivpu_hw_mtl_irqb_handler(vdev, irq); + /* Re-enable global interrupts to re-trigger MSI for pending interrupts */ + REGB_WR32(MTL_BUTTRESS_GLOBAL_INT_MASK, 0x0); + return IRQ_RETVAL(ret_irqb | ret_irqv); } -- 2.34.1

1 year, 2 months

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FAILED: patch "[PATCH] nfsd: lock_rename() needs both directories to live on the" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 1aee9158bc978f91701c5992e395efbc6da2de3c # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023102701-cadet-groovy-9672@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 1aee9158bc978f91701c5992e395efbc6da2de3c Mon Sep 17 00:00:00 2001 From: Al Viro <viro(a)zeniv.linux.org.uk> Date: Sat, 14 Oct 2023 21:34:40 -0400 Subject: [PATCH] nfsd: lock_rename() needs both directories to live on the same fs ... checking that after lock_rename() is too late. Incidentally, NFSv2 had no nfserr_xdev... Fixes: aa387d6ce153 "nfsd: fix EXDEV checking in rename" Cc: stable(a)vger.kernel.org # v3.9+ Reviewed-by: Jeff Layton <jlayton(a)kernel.org> Acked-by: Chuck Lever <chuck.lever(a)oracle.com> Tested-by: Jeff Layton <jlayton(a)kernel.org> Signed-off-by: Al Viro <viro(a)zeniv.linux.org.uk> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 48260cf68fde..02f5fcaad03f 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1788,6 +1788,12 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen)) goto out; + err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev; + if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt) + goto out; + if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry) + goto out; + retry: host_err = fh_want_write(ffhp); if (host_err) { @@ -1823,12 +1829,6 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, if (ndentry == trap) goto out_dput_new; - host_err = -EXDEV; - if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt) - goto out_dput_new; - if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry) - goto out_dput_new; - if ((ndentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK) && nfsd_has_cached_files(ndentry)) { close_cached = true;

1 year, 2 months

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[PATCH 4.19] f2fs: fix to do sanity check on inode type during garbage collection

by Kazunori Kobayashi

From: Chao Yu <chao(a)kernel.org> commit 9056d6489f5a41cfbb67f719d2c0ce61ead72d9f upstream. As report by Wenqing Liu in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215231 - Overview kernel NULL pointer dereference triggered in folio_mark_dirty() when mount and operate on a crafted f2fs image - Reproduce tested on kernel 5.16-rc3, 5.15.X under root 1. mkdir mnt 2. mount -t f2fs tmp1.img mnt 3. touch tmp 4. cp tmp mnt F2FS-fs (loop0): sanity_check_inode: inode (ino=49) extent info [5942, 4294180864, 4] is incorrect, run fsck to fix F2FS-fs (loop0): f2fs_check_nid_range: out-of-range nid=31340049, run fsck to fix. BUG: kernel NULL pointer dereference, address: 0000000000000000 folio_mark_dirty+0x33/0x50 move_data_page+0x2dd/0x460 [f2fs] do_garbage_collect+0xc18/0x16a0 [f2fs] f2fs_gc+0x1d3/0xd90 [f2fs] f2fs_balance_fs+0x13a/0x570 [f2fs] f2fs_create+0x285/0x840 [f2fs] path_openat+0xe6d/0x1040 do_filp_open+0xc5/0x140 do_sys_openat2+0x23a/0x310 do_sys_open+0x57/0x80 The root cause is for special file: e.g. character, block, fifo or socket file, f2fs doesn't assign address space operations pointer array for mapping->a_ops field, so, in a fuzzed image, SSA table indicates a data block belong to special file, when f2fs tries to migrate that block, it causes NULL pointer access once move_data_page() calls a_ops->set_dirty_page(). Cc: stable(a)vger.kernel.org Reported-by: Wenqing Liu <wenqingliu0120(a)gmail.com> Signed-off-by: Chao Yu <chao(a)kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk(a)kernel.org> Signed-off-by: Kazunori Kobayashi <kazunori.kobayashi(a)miraclelinux.com> --- fs/f2fs/gc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index ff447bbb5248..fb4494c54484 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -958,7 +958,8 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, if (phase == 3) { inode = f2fs_iget(sb, dni.ino); - if (IS_ERR(inode) || is_bad_inode(inode)) + if (IS_ERR(inode) || is_bad_inode(inode) || + special_file(inode->i_mode)) continue; if (!down_write_trylock( -- 2.39.2

1 year, 2 months

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[PATCH 5.10 0/1] smbdirect: missing rc checks while waiting for rdma events

by Anastasia Belova

Check for return value of wait_for_completion_interruptible_timeout should be added in v5.10. The following patch contains necessary changes and can be cleanly applied. Found by Linux Verification Center (linuxtesting.org) with Svace.

1 year, 2 months

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[PATCH 5.10 0/1] kobject: backport of slab-out-of-bounds fix

by Oleksandr Tymoshenko

This is a backport of slab-out-of-bounds fix to 5.10. The only change from the original is adjustment of fill_kobj_path signature. Wang Hai (1): kobject: Fix slab-out-of-bounds in fill_kobj_path() lib/kobject.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) -- 2.42.0.758.gaed0368e0e-goog

1 year, 2 months

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[PATCH v4.19.y 1/6] driver: platform: Add helper for safer setting of driver_override

by Lee Jones

From: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> commit 6c2f421174273de8f83cde4286d1c076d43a2d35 upstream. Several core drivers and buses expect that driver_override is a dynamically allocated memory thus later they can kfree() it. However such assumption is not documented, there were in the past and there are already users setting it to a string literal. This leads to kfree() of static memory during device release (e.g. in error paths or during unbind): kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [<c058da50>] (platform_device_release+0x88/0xb4) (platform_device_release) from [<c0585be0>] (device_release+0x2c/0x90) (device_release) from [<c0a69050>] (kobject_put+0xec/0x20c) (kobject_put) from [<c0f2f120>] (exynos5_clk_probe+0x154/0x18c) (exynos5_clk_probe) from [<c058de70>] (platform_drv_probe+0x6c/0xa4) (platform_drv_probe) from [<c058b7ac>] (really_probe+0x280/0x414) (really_probe) from [<c058baf4>] (driver_probe_device+0x78/0x1c4) (driver_probe_device) from [<c0589854>] (bus_for_each_drv+0x74/0xb8) (bus_for_each_drv) from [<c058b48c>] (__device_attach+0xd4/0x16c) (__device_attach) from [<c058a638>] (bus_probe_device+0x88/0x90) (bus_probe_device) from [<c05871fc>] (device_add+0x3dc/0x62c) (device_add) from [<c075ff10>] (of_platform_device_create_pdata+0x94/0xbc) (of_platform_device_create_pdata) from [<c07600ec>] (of_platform_bus_create+0x1a8/0x4fc) (of_platform_bus_create) from [<c0760150>] (of_platform_bus_create+0x20c/0x4fc) (of_platform_bus_create) from [<c07605f0>] (of_platform_populate+0x84/0x118) (of_platform_populate) from [<c0f3c964>] (of_platform_default_populate_init+0xa0/0xb8) (of_platform_default_populate_init) from [<c01031f8>] (do_one_initcall+0x8c/0x404) Provide a helper which clearly documents the usage of driver_override. This will allow later to reuse the helper and reduce the amount of duplicated code. Convert the platform driver to use a new helper and make the driver_override field const char (it is not modified by the core). Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> Link: https://lore.kernel.org/r/20220419113435.246203-2-krzysztof.kozlowski@linar… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lee Jones <lee(a)kernel.org> --- drivers/base/driver.c | 69 +++++++++++++++++++++++++++++++++ drivers/base/platform.c | 28 ++----------- include/linux/device.h | 2 + include/linux/platform_device.h | 6 ++- 4 files changed, 80 insertions(+), 25 deletions(-) diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 857c8f1b876e5..668c6c8c22f1f 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -29,6 +29,75 @@ static struct device *next_device(struct klist_iter *i) return dev; } +/** + * driver_set_override() - Helper to set or clear driver override. + * @dev: Device to change + * @override: Address of string to change (e.g. &device->driver_override); + * The contents will be freed and hold newly allocated override. + * @s: NUL-terminated string, new driver name to force a match, pass empty + * string to clear it ("" or "\n", where the latter is only for sysfs + * interface). + * @len: length of @s + * + * Helper to set or clear driver override in a device, intended for the cases + * when the driver_override field is allocated by driver/bus code. + * + * Returns: 0 on success or a negative error code on failure. + */ +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len) +{ + const char *new, *old; + char *cp; + + if (!override || !s) + return -EINVAL; + + /* + * The stored value will be used in sysfs show callback (sysfs_emit()), + * which has a length limit of PAGE_SIZE and adds a trailing newline. + * Thus we can store one character less to avoid truncation during sysfs + * show. + */ + if (len >= (PAGE_SIZE - 1)) + return -EINVAL; + + if (!len) { + /* Empty string passed - clear override */ + device_lock(dev); + old = *override; + *override = NULL; + device_unlock(dev); + kfree(old); + + return 0; + } + + cp = strnchr(s, len, '\n'); + if (cp) + len = cp - s; + + new = kstrndup(s, len, GFP_KERNEL); + if (!new) + return -ENOMEM; + + device_lock(dev); + old = *override; + if (cp != s) { + *override = new; + } else { + /* "\n" passed - clear override */ + kfree(new); + *override = NULL; + } + device_unlock(dev); + + kfree(old); + + return 0; +} +EXPORT_SYMBOL_GPL(driver_set_override); + /** * driver_for_each_device - Iterator for devices bound to a driver. * @drv: Driver we're iterating. diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 2f89e618b142c..a09e7a681f7a7 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -891,31 +891,11 @@ static ssize_t driver_override_store(struct device *dev, const char *buf, size_t count) { struct platform_device *pdev = to_platform_device(dev); - char *driver_override, *old, *cp; - - /* We need to keep extra room for a newline */ - if (count >= (PAGE_SIZE - 1)) - return -EINVAL; - - driver_override = kstrndup(buf, count, GFP_KERNEL); - if (!driver_override) - return -ENOMEM; - - cp = strchr(driver_override, '\n'); - if (cp) - *cp = '\0'; - - device_lock(dev); - old = pdev->driver_override; - if (strlen(driver_override)) { - pdev->driver_override = driver_override; - } else { - kfree(driver_override); - pdev->driver_override = NULL; - } - device_unlock(dev); + int ret; - kfree(old); + ret = driver_set_override(dev, &pdev->driver_override, buf, count); + if (ret) + return ret; return count; } diff --git a/include/linux/device.h b/include/linux/device.h index 37e359d81a86f..bccd367c11de5 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -330,6 +330,8 @@ extern int __must_check driver_create_file(struct device_driver *driver, extern void driver_remove_file(struct device_driver *driver, const struct driver_attribute *attr); +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len); extern int __must_check driver_for_each_device(struct device_driver *drv, struct device *start, void *data, diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 9e5c98fcea8c6..8268439975b21 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -29,7 +29,11 @@ struct platform_device { struct resource *resource; const struct platform_device_id *id_entry; - char *driver_override; /* Driver name to force a match */ + /* + * Driver name to force a match. Do not set directly, because core + * frees it. Use driver_set_override() to set or clear it. + */ + const char *driver_override; /* MFD cell pointer */ struct mfd_cell *mfd_cell; -- 2.42.0.820.g83a721a137-goog

1 year, 2 months

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[PATCH v5.4.y 1/6] driver: platform: Add helper for safer setting of driver_override

by Lee Jones

From: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> commit 6c2f421174273de8f83cde4286d1c076d43a2d35 upstream. Several core drivers and buses expect that driver_override is a dynamically allocated memory thus later they can kfree() it. However such assumption is not documented, there were in the past and there are already users setting it to a string literal. This leads to kfree() of static memory during device release (e.g. in error paths or during unbind): kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [<c058da50>] (platform_device_release+0x88/0xb4) (platform_device_release) from [<c0585be0>] (device_release+0x2c/0x90) (device_release) from [<c0a69050>] (kobject_put+0xec/0x20c) (kobject_put) from [<c0f2f120>] (exynos5_clk_probe+0x154/0x18c) (exynos5_clk_probe) from [<c058de70>] (platform_drv_probe+0x6c/0xa4) (platform_drv_probe) from [<c058b7ac>] (really_probe+0x280/0x414) (really_probe) from [<c058baf4>] (driver_probe_device+0x78/0x1c4) (driver_probe_device) from [<c0589854>] (bus_for_each_drv+0x74/0xb8) (bus_for_each_drv) from [<c058b48c>] (__device_attach+0xd4/0x16c) (__device_attach) from [<c058a638>] (bus_probe_device+0x88/0x90) (bus_probe_device) from [<c05871fc>] (device_add+0x3dc/0x62c) (device_add) from [<c075ff10>] (of_platform_device_create_pdata+0x94/0xbc) (of_platform_device_create_pdata) from [<c07600ec>] (of_platform_bus_create+0x1a8/0x4fc) (of_platform_bus_create) from [<c0760150>] (of_platform_bus_create+0x20c/0x4fc) (of_platform_bus_create) from [<c07605f0>] (of_platform_populate+0x84/0x118) (of_platform_populate) from [<c0f3c964>] (of_platform_default_populate_init+0xa0/0xb8) (of_platform_default_populate_init) from [<c01031f8>] (do_one_initcall+0x8c/0x404) Provide a helper which clearly documents the usage of driver_override. This will allow later to reuse the helper and reduce the amount of duplicated code. Convert the platform driver to use a new helper and make the driver_override field const char (it is not modified by the core). Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> Link: https://lore.kernel.org/r/20220419113435.246203-2-krzysztof.kozlowski@linar… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lee Jones <lee(a)kernel.org> --- drivers/base/driver.c | 69 +++++++++++++++++++++++++++++++++ drivers/base/platform.c | 28 ++----------- include/linux/device.h | 2 + include/linux/platform_device.h | 6 ++- 4 files changed, 80 insertions(+), 25 deletions(-) diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 4e5ca632f35e8..ef14566a49710 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -29,6 +29,75 @@ static struct device *next_device(struct klist_iter *i) return dev; } +/** + * driver_set_override() - Helper to set or clear driver override. + * @dev: Device to change + * @override: Address of string to change (e.g. &device->driver_override); + * The contents will be freed and hold newly allocated override. + * @s: NUL-terminated string, new driver name to force a match, pass empty + * string to clear it ("" or "\n", where the latter is only for sysfs + * interface). + * @len: length of @s + * + * Helper to set or clear driver override in a device, intended for the cases + * when the driver_override field is allocated by driver/bus code. + * + * Returns: 0 on success or a negative error code on failure. + */ +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len) +{ + const char *new, *old; + char *cp; + + if (!override || !s) + return -EINVAL; + + /* + * The stored value will be used in sysfs show callback (sysfs_emit()), + * which has a length limit of PAGE_SIZE and adds a trailing newline. + * Thus we can store one character less to avoid truncation during sysfs + * show. + */ + if (len >= (PAGE_SIZE - 1)) + return -EINVAL; + + if (!len) { + /* Empty string passed - clear override */ + device_lock(dev); + old = *override; + *override = NULL; + device_unlock(dev); + kfree(old); + + return 0; + } + + cp = strnchr(s, len, '\n'); + if (cp) + len = cp - s; + + new = kstrndup(s, len, GFP_KERNEL); + if (!new) + return -ENOMEM; + + device_lock(dev); + old = *override; + if (cp != s) { + *override = new; + } else { + /* "\n" passed - clear override */ + kfree(new); + *override = NULL; + } + device_unlock(dev); + + kfree(old); + + return 0; +} +EXPORT_SYMBOL_GPL(driver_set_override); + /** * driver_for_each_device - Iterator for devices bound to a driver. * @drv: Driver we're iterating. diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 75623b914b8c2..0ed43d185a900 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -973,31 +973,11 @@ static ssize_t driver_override_store(struct device *dev, const char *buf, size_t count) { struct platform_device *pdev = to_platform_device(dev); - char *driver_override, *old, *cp; - - /* We need to keep extra room for a newline */ - if (count >= (PAGE_SIZE - 1)) - return -EINVAL; - - driver_override = kstrndup(buf, count, GFP_KERNEL); - if (!driver_override) - return -ENOMEM; - - cp = strchr(driver_override, '\n'); - if (cp) - *cp = '\0'; - - device_lock(dev); - old = pdev->driver_override; - if (strlen(driver_override)) { - pdev->driver_override = driver_override; - } else { - kfree(driver_override); - pdev->driver_override = NULL; - } - device_unlock(dev); + int ret; - kfree(old); + ret = driver_set_override(dev, &pdev->driver_override, buf, count); + if (ret) + return ret; return count; } diff --git a/include/linux/device.h b/include/linux/device.h index c7be3a8073ec3..af4ecbf889107 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -422,6 +422,8 @@ extern int __must_check driver_create_file(struct device_driver *driver, extern void driver_remove_file(struct device_driver *driver, const struct driver_attribute *attr); +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len); extern int __must_check driver_for_each_device(struct device_driver *drv, struct device *start, void *data, diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 569f446502bed..c7bd8a1a60976 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -29,7 +29,11 @@ struct platform_device { struct resource *resource; const struct platform_device_id *id_entry; - char *driver_override; /* Driver name to force a match */ + /* + * Driver name to force a match. Do not set directly, because core + * frees it. Use driver_set_override() to set or clear it. + */ + const char *driver_override; /* MFD cell pointer */ struct mfd_cell *mfd_cell; -- 2.42.0.820.g83a721a137-goog

1 year, 2 months

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[PATCH v5.10.y 1/6] driver: platform: Add helper for safer setting of driver_override

by Lee Jones

From: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> commit 6c2f421174273de8f83cde4286d1c076d43a2d35 upstream. Several core drivers and buses expect that driver_override is a dynamically allocated memory thus later they can kfree() it. However such assumption is not documented, there were in the past and there are already users setting it to a string literal. This leads to kfree() of static memory during device release (e.g. in error paths or during unbind): kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [<c058da50>] (platform_device_release+0x88/0xb4) (platform_device_release) from [<c0585be0>] (device_release+0x2c/0x90) (device_release) from [<c0a69050>] (kobject_put+0xec/0x20c) (kobject_put) from [<c0f2f120>] (exynos5_clk_probe+0x154/0x18c) (exynos5_clk_probe) from [<c058de70>] (platform_drv_probe+0x6c/0xa4) (platform_drv_probe) from [<c058b7ac>] (really_probe+0x280/0x414) (really_probe) from [<c058baf4>] (driver_probe_device+0x78/0x1c4) (driver_probe_device) from [<c0589854>] (bus_for_each_drv+0x74/0xb8) (bus_for_each_drv) from [<c058b48c>] (__device_attach+0xd4/0x16c) (__device_attach) from [<c058a638>] (bus_probe_device+0x88/0x90) (bus_probe_device) from [<c05871fc>] (device_add+0x3dc/0x62c) (device_add) from [<c075ff10>] (of_platform_device_create_pdata+0x94/0xbc) (of_platform_device_create_pdata) from [<c07600ec>] (of_platform_bus_create+0x1a8/0x4fc) (of_platform_bus_create) from [<c0760150>] (of_platform_bus_create+0x20c/0x4fc) (of_platform_bus_create) from [<c07605f0>] (of_platform_populate+0x84/0x118) (of_platform_populate) from [<c0f3c964>] (of_platform_default_populate_init+0xa0/0xb8) (of_platform_default_populate_init) from [<c01031f8>] (do_one_initcall+0x8c/0x404) Provide a helper which clearly documents the usage of driver_override. This will allow later to reuse the helper and reduce the amount of duplicated code. Convert the platform driver to use a new helper and make the driver_override field const char (it is not modified by the core). Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> Link: https://lore.kernel.org/r/20220419113435.246203-2-krzysztof.kozlowski@linar… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lee Jones <lee(a)kernel.org> --- drivers/base/driver.c | 69 +++++++++++++++++++++++++++++++++ drivers/base/platform.c | 28 ++----------- include/linux/device/driver.h | 2 + include/linux/platform_device.h | 6 ++- 4 files changed, 80 insertions(+), 25 deletions(-) diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 8c0d33e182fd5..1b9d47b10bd0a 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -30,6 +30,75 @@ static struct device *next_device(struct klist_iter *i) return dev; } +/** + * driver_set_override() - Helper to set or clear driver override. + * @dev: Device to change + * @override: Address of string to change (e.g. &device->driver_override); + * The contents will be freed and hold newly allocated override. + * @s: NUL-terminated string, new driver name to force a match, pass empty + * string to clear it ("" or "\n", where the latter is only for sysfs + * interface). + * @len: length of @s + * + * Helper to set or clear driver override in a device, intended for the cases + * when the driver_override field is allocated by driver/bus code. + * + * Returns: 0 on success or a negative error code on failure. + */ +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len) +{ + const char *new, *old; + char *cp; + + if (!override || !s) + return -EINVAL; + + /* + * The stored value will be used in sysfs show callback (sysfs_emit()), + * which has a length limit of PAGE_SIZE and adds a trailing newline. + * Thus we can store one character less to avoid truncation during sysfs + * show. + */ + if (len >= (PAGE_SIZE - 1)) + return -EINVAL; + + if (!len) { + /* Empty string passed - clear override */ + device_lock(dev); + old = *override; + *override = NULL; + device_unlock(dev); + kfree(old); + + return 0; + } + + cp = strnchr(s, len, '\n'); + if (cp) + len = cp - s; + + new = kstrndup(s, len, GFP_KERNEL); + if (!new) + return -ENOMEM; + + device_lock(dev); + old = *override; + if (cp != s) { + *override = new; + } else { + /* "\n" passed - clear override */ + kfree(new); + *override = NULL; + } + device_unlock(dev); + + kfree(old); + + return 0; +} +EXPORT_SYMBOL_GPL(driver_set_override); + /** * driver_for_each_device - Iterator for devices bound to a driver. * @drv: Driver we're iterating. diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 88aef93eb4ddf..647066229fec3 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -1046,31 +1046,11 @@ static ssize_t driver_override_store(struct device *dev, const char *buf, size_t count) { struct platform_device *pdev = to_platform_device(dev); - char *driver_override, *old, *cp; - - /* We need to keep extra room for a newline */ - if (count >= (PAGE_SIZE - 1)) - return -EINVAL; - - driver_override = kstrndup(buf, count, GFP_KERNEL); - if (!driver_override) - return -ENOMEM; - - cp = strchr(driver_override, '\n'); - if (cp) - *cp = '\0'; - - device_lock(dev); - old = pdev->driver_override; - if (strlen(driver_override)) { - pdev->driver_override = driver_override; - } else { - kfree(driver_override); - pdev->driver_override = NULL; - } - device_unlock(dev); + int ret; - kfree(old); + ret = driver_set_override(dev, &pdev->driver_override, buf, count); + if (ret) + return ret; return count; } diff --git a/include/linux/device/driver.h b/include/linux/device/driver.h index ee7ba5b5417e5..a44f5adeaef5a 100644 --- a/include/linux/device/driver.h +++ b/include/linux/device/driver.h @@ -150,6 +150,8 @@ extern int __must_check driver_create_file(struct device_driver *driver, extern void driver_remove_file(struct device_driver *driver, const struct driver_attribute *attr); +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len); extern int __must_check driver_for_each_device(struct device_driver *drv, struct device *start, void *data, diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 17f9cd5626c83..e7a83b0218077 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -30,7 +30,11 @@ struct platform_device { struct resource *resource; const struct platform_device_id *id_entry; - char *driver_override; /* Driver name to force a match */ + /* + * Driver name to force a match. Do not set directly, because core + * frees it. Use driver_set_override() to set or clear it. + */ + const char *driver_override; /* MFD cell pointer */ struct mfd_cell *mfd_cell; -- 2.42.0.820.g83a721a137-goog

1 year, 2 months

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[PATCH v5.15.y 1/6] driver: platform: Add helper for safer setting of driver_override

by Lee Jones

From: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> commit 6c2f421174273de8f83cde4286d1c076d43a2d35 upstream. Several core drivers and buses expect that driver_override is a dynamically allocated memory thus later they can kfree() it. However such assumption is not documented, there were in the past and there are already users setting it to a string literal. This leads to kfree() of static memory during device release (e.g. in error paths or during unbind): kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [<c058da50>] (platform_device_release+0x88/0xb4) (platform_device_release) from [<c0585be0>] (device_release+0x2c/0x90) (device_release) from [<c0a69050>] (kobject_put+0xec/0x20c) (kobject_put) from [<c0f2f120>] (exynos5_clk_probe+0x154/0x18c) (exynos5_clk_probe) from [<c058de70>] (platform_drv_probe+0x6c/0xa4) (platform_drv_probe) from [<c058b7ac>] (really_probe+0x280/0x414) (really_probe) from [<c058baf4>] (driver_probe_device+0x78/0x1c4) (driver_probe_device) from [<c0589854>] (bus_for_each_drv+0x74/0xb8) (bus_for_each_drv) from [<c058b48c>] (__device_attach+0xd4/0x16c) (__device_attach) from [<c058a638>] (bus_probe_device+0x88/0x90) (bus_probe_device) from [<c05871fc>] (device_add+0x3dc/0x62c) (device_add) from [<c075ff10>] (of_platform_device_create_pdata+0x94/0xbc) (of_platform_device_create_pdata) from [<c07600ec>] (of_platform_bus_create+0x1a8/0x4fc) (of_platform_bus_create) from [<c0760150>] (of_platform_bus_create+0x20c/0x4fc) (of_platform_bus_create) from [<c07605f0>] (of_platform_populate+0x84/0x118) (of_platform_populate) from [<c0f3c964>] (of_platform_default_populate_init+0xa0/0xb8) (of_platform_default_populate_init) from [<c01031f8>] (do_one_initcall+0x8c/0x404) Provide a helper which clearly documents the usage of driver_override. This will allow later to reuse the helper and reduce the amount of duplicated code. Convert the platform driver to use a new helper and make the driver_override field const char (it is not modified by the core). Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> Link: https://lore.kernel.org/r/20220419113435.246203-2-krzysztof.kozlowski@linar… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lee Jones <lee(a)kernel.org> --- drivers/base/driver.c | 69 +++++++++++++++++++++++++++++++++ drivers/base/platform.c | 28 ++----------- include/linux/device/driver.h | 2 + include/linux/platform_device.h | 6 ++- 4 files changed, 80 insertions(+), 25 deletions(-) diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 8c0d33e182fd5..1b9d47b10bd0a 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -30,6 +30,75 @@ static struct device *next_device(struct klist_iter *i) return dev; } +/** + * driver_set_override() - Helper to set or clear driver override. + * @dev: Device to change + * @override: Address of string to change (e.g. &device->driver_override); + * The contents will be freed and hold newly allocated override. + * @s: NUL-terminated string, new driver name to force a match, pass empty + * string to clear it ("" or "\n", where the latter is only for sysfs + * interface). + * @len: length of @s + * + * Helper to set or clear driver override in a device, intended for the cases + * when the driver_override field is allocated by driver/bus code. + * + * Returns: 0 on success or a negative error code on failure. + */ +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len) +{ + const char *new, *old; + char *cp; + + if (!override || !s) + return -EINVAL; + + /* + * The stored value will be used in sysfs show callback (sysfs_emit()), + * which has a length limit of PAGE_SIZE and adds a trailing newline. + * Thus we can store one character less to avoid truncation during sysfs + * show. + */ + if (len >= (PAGE_SIZE - 1)) + return -EINVAL; + + if (!len) { + /* Empty string passed - clear override */ + device_lock(dev); + old = *override; + *override = NULL; + device_unlock(dev); + kfree(old); + + return 0; + } + + cp = strnchr(s, len, '\n'); + if (cp) + len = cp - s; + + new = kstrndup(s, len, GFP_KERNEL); + if (!new) + return -ENOMEM; + + device_lock(dev); + old = *override; + if (cp != s) { + *override = new; + } else { + /* "\n" passed - clear override */ + kfree(new); + *override = NULL; + } + device_unlock(dev); + + kfree(old); + + return 0; +} +EXPORT_SYMBOL_GPL(driver_set_override); + /** * driver_for_each_device - Iterator for devices bound to a driver. * @drv: Driver we're iterating. diff --git a/drivers/base/platform.c b/drivers/base/platform.c index ac5cf1a8d79ab..596fbe6b701a5 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -1270,31 +1270,11 @@ static ssize_t driver_override_store(struct device *dev, const char *buf, size_t count) { struct platform_device *pdev = to_platform_device(dev); - char *driver_override, *old, *cp; - - /* We need to keep extra room for a newline */ - if (count >= (PAGE_SIZE - 1)) - return -EINVAL; - - driver_override = kstrndup(buf, count, GFP_KERNEL); - if (!driver_override) - return -ENOMEM; - - cp = strchr(driver_override, '\n'); - if (cp) - *cp = '\0'; - - device_lock(dev); - old = pdev->driver_override; - if (strlen(driver_override)) { - pdev->driver_override = driver_override; - } else { - kfree(driver_override); - pdev->driver_override = NULL; - } - device_unlock(dev); + int ret; - kfree(old); + ret = driver_set_override(dev, &pdev->driver_override, buf, count); + if (ret) + return ret; return count; } diff --git a/include/linux/device/driver.h b/include/linux/device/driver.h index a498ebcf49933..abf948e102f5d 100644 --- a/include/linux/device/driver.h +++ b/include/linux/device/driver.h @@ -150,6 +150,8 @@ extern int __must_check driver_create_file(struct device_driver *driver, extern void driver_remove_file(struct device_driver *driver, const struct driver_attribute *attr); +int driver_set_override(struct device *dev, const char **override, + const char *s, size_t len); extern int __must_check driver_for_each_device(struct device_driver *drv, struct device *start, void *data, diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 8aefdc0099c86..72cf70857b85f 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -31,7 +31,11 @@ struct platform_device { struct resource *resource; const struct platform_device_id *id_entry; - char *driver_override; /* Driver name to force a match */ + /* + * Driver name to force a match. Do not set directly, because core + * frees it. Use driver_set_override() to set or clear it. + */ + const char *driver_override; /* MFD cell pointer */ struct mfd_cell *mfd_cell; -- 2.42.0.820.g83a721a137-goog

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Linux-stable-mirror October 2023